86
PERSONALITY CHARACTERISTICS OF SEX OFFENDERS: A COMPARISON OF THE MMPI AND MCMI Shelly C. OfConnor B.A. (Hons), University of Victoria, 1986 THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF ARTS , Department of Psychology @ Shelly C. OIConnor 1990 SIMON FRASER UNIVERSITY November 1990 All rights resewed. This work may not be reproduced in whole or in part, by photocopy or other means, without permission of the author.

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Page 1: Personality characteristics of sex offenders : a ... · iii . offenses 'that most often included one extrafamilial victim of eleven years old or older, ... MCMI demonstrated superior

PERSONALITY CHARACTERISTICS OF SEX OFFENDERS:

A COMPARISON OF THE MMPI AND MCMI

Shelly C. OfConnor

B.A. (Hons), University of Victoria, 1986

THESIS SUBMITTED IN PARTIAL FULFILLMENT OF

THE REQUIREMENTS FOR THE DEGREE OF

MASTER OF ARTS

, Department

of

Psychology

@ Shelly C. OIConnor 1990

SIMON FRASER UNIVERSITY

November 1990

All rights resewed. This work may not be reproduced in whole or in part, by photocopy

or other means, without permission of the author.

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APPROVAL

Name : Shelly Charlene OIConnor

Degree: Master of Arts

Title of Thesis: Personality characteristics of Sex Offenders:

A comparison of the MMPI and MCMI

Examining Committee:

Chairperson: Dr. Marilyn Bowman

Dr. Richard J. Freeman Senior Supervisor

Dr. DWid N. Cox

Dr. Carson W. smiley External Examiner Director of Psychosocial Services Regional Psychiatric Centre Correctional Services of Canada

Date Approved: -

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PARTIAL COPYRIGHT LICENSE

I hereby grant t o Simon Fraser U n i v e r s i t y the r i g h t t o lend

my thes i s , p r o j e c t o r extended essay ( the t i t l e of which i s shown below)

t o users o f the Simon Fraser U n i v e r s i t y L ib ra ry , and t o make p a r t i a l o r

s i n g l e copies on l y f o r such users o r i n response t o a request from the

l i b r a r y o f any o the r u n i v e r s i t y , o r o ther educat ional i n s t i t u t i o n , on

i t s own beha l f o r f o r one o f i t s users. I f u r t h e r agree t h a t permission

f o r m u l t i p l e copying o f t h i s work f o r scho la r l y purposes may be granted

by me o r the Dean o f Graduate Stydies. I t i s understood t h a t copying

o r p u b l i c a t i o n o f t h i s work f o r f i n a n c i a l gain s h a l l no t be al lowed

w i thou t my w r i t t e n permission.

T i t l e o f Thesis/Project/Extended Essay

Personality Characteristics of Sex Offenders: -.

A Coqarison of the MMPI and MCMI

Author:

( s i g$ature)

: Shelly Charlene OIConnor

(name)

(date)

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Abstract

This study examined the relative utility of the

Minnesota Multiphasic Personality Inventory (MMPI) and the

Millon Clinical Multiaxial Inventory (MCMI) in

differentiating adult males who had committed sexual

offenses. To date, the MMPI has been largely unsuccessful

at differentiating types of sex offenders. A partial

explanation for inconsistent results is the relative

infrequency in the sex offender population of those clinical

syndromes xis I of DSM-111-R) best captured by the MMPI.

It was hypothesized that sex offenders are more likely to

harbour personality disorders (Axik 11), which the MCMI is

specifically designed to assess.

A sample of 127 adult males who had committed sexual

offenses was studied using personality factors (derived from

the MMPI and MCMI separately) and offender characteristics

to predict offense type. Results showed that offender

variables yielded three meaningful solutions when submitted

to cluster analysis. These included an Unskilled Labour

group, an Unemployed group who, and a Skilled Labour group.

Offense/victim variables also yielded three meaningful

cluster solutions. These were Intrafamilial offenses that

typically included one intrafamilial victim who was ten

years old or younger, 20 or more offense repeats of a

relatively serious nature (i.e. the offense included oral

sex; digital, vaginal, and/or anal penetration); ~mpulsive

iii

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offenses 'that most often included one extrafamilial victim

of eleven years old or older, a one-time occurrence, and of

a relatively less serious nature (e.g., exhibitionism,

obscene phone calls, or fondling and/or masturbation);

Chronic offenses that included two or more victims who were

ten years old or younger, between two and 19 offense repeats

that were of a relatively serious nature and tended to be

both intrafamilial and extrafamilial.

The MMPI and MCMI each produced four meaningful

personality factors. These personality factors and the

offender clusters were used to predict offense type. The

MCMI demonstrated superior predictive validity in that it

discriminated the Chronic from the Intrafamilial offenses,

as well as the average of these two offense groups from the

Impulsive offenses. The MMPI only discriminated the Chronic >

from the ~ntrafamilial offenses. Implications for treatment

and recidivism were discussed within the context of

personality characteristics.

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Acknowledgements

I would like to thank Richard Freeman for his support

and encouragement. Without his gentle nudging, I may still

be working on this. Also, I would like to thank Louis

Sutker for his generous sharing of data and relevant

literature. Thanks go out as well to Angela, Doug, Karen,

and Sue, for their feedback, which made all the difference

in @@Defense Postmortemst1. A special thank you to Michael

for his guidance, patience, and support for the duration of

this project, and most importantly for his Itway of being in

the worldl1. Additional people who were instrumental in

providing much appreciated help were David Cox, Carson

Smiley, and Lorie Tarcea. Finally, I would like to thank my

mother, Gail, for being there in many ways for me throughout I

the course of my graduate career, and my father, Thomas, who

although isnlt quite sure exactly what it is I am doing,

thinks it's wonderful anyway.

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TABLE! OF CONTENTS

Approval ......................................... ii Abstract ........................................ iii Acknowledgements ................................. v List of Tables ................................... vii I . Introduction ............................... 1

MMPI Research with Sex Offenders ........... 3 Sample Selection ........................... 5 Definition of Groups ....................... 6 ~efinition of MMPI Protocol Validity ....... 13 Statistical Analysis of MMPI Profiles ...... 15 MMPI Scores Reported ....................... 16 MMPI Results in Sex Offender Studies ....... 17 The Millon Clinical Multiaxial Inventory ... 22 Purpose of Fresent Study ................... 24

I1 . Method ..................................... 25 Subjects ................................... 25 Procedure .................................. 25

I11 . Results .................................... 28 IV . Discussion ................................. 58

................................. V . References 74

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Table

LIST OF TABLES

Page

1. Different Groups Used in MMPI ..................... Research with Sex Offenders 9

........... 2. MMPI and MCMI Means for Total Sample 31

........... 3. Order Independent MMPI 2-Point Codes 31

4. Frequency and Percentage of Subjects ......... in Total Sample with MMPJ T-scores >69 32

5. Order Independent MCMI 2-Point Codes ............ and Highest single Scale Elevations 32

6. Frequency and Percentage of subjects ........ in Total Sample with MCMI BR Scores >75 34

7 . Contingency Coefficients Among Offender Variables ............................. 35

8. Contingency Coefficients Among .............................. Offense Variables 38

9. Contingency coefficients Among Offense and Offender Variables ................. 38

? ..................... 10. MMPI Rotated Factor Matrix 40

..................... 11. MCMI Rotated Factor Matrix 42

12. Pearson Correlation Matrix of MMPI and MCMI Factors ............................... 42

13. Set Correlation Analysis of Offender and Personality Variables Related to Coded Set of Offense ...................................... Variables 53

14. Set Correlation Analysis of Intrafamilial Group Versus .................................. Chronic Group 54

15. Set correlation ~nalysis of the ~mpulsive Group Versus the Average of the ~ntrafamilial ............................. and Chronic Groups 55

16. Summary of Set Correlation ...................................... Analysis 56

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CHAPTER I

INTRODUCTION

This study investigated the personality characteristics

of various subgroups of sex offenders. More specifically,

Minnesota ~ultiphasic Personality Inventory (MMPI) and

Millon clinical ~ultiaxial Inventory (MCMI) profiles were

compared to determine which instrument better classified sex

offenders into subgroups differing in offense type, victim

characteristics, and offender variables. The section to

follow describes the prevalence and problem of sexual

offending, and reviews the literature on MMPI research with

sex offenders. The section will conclude by introducing the

MCMI, and proposing a rationale for including this

instrument in the present study.

The term sexual offense refers to a wide range of

illegal sexual behaviors, including rape, child molestation,

incest, and indecent exposure. In British Columbia the

number of adults charged with sex offenses has increased

dramatically from 495 in 1980 to 1003 in 1985. These 1003

individuals were charged with 3,669 sex offenses. Thus, an

average of about ten sex offenses were committed every day

(LaTorre, 1987). Given this trend, the numbers of persons

charged with sex offenses likely is even higher at present.

LaTorre (1987) suggests several factors that may have

contributed to this increase, including better reporting

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procedures, more aggressive prosecution, and amended

definitions of sexual offenses under the Criminal Code

introduced in 1985. LaTorre (1987) acknowledges, however,

that the increase in charges must partly be attributed to a

real increase in the incidence of sex offenses.

~ccording to an estimate put forth in the Badgley

Report prepared by the federal government in 1984, one in

ten boys and one in four girls are sexually assaulted as

children. Clearly, sex offenses constitute a serious social

problem, and the body of research devoted to this topic is

expanding at a rapid rate.

One issue that has received considerable attention

concerns assessing the personality characteristics of sex

offenders. Research investigating the personality

characteristics of sex offenders typically assesses

personality using the MMPI. It is therefore important to

determine the utility of the MMPI in differentiating sex

offenders from offenders convicted of other non-sex crimes

and in differentiating various subgroups of sex offenders.

Large numbers of persons charged with sexual offense(s)

are referred by the courts for a psychiatric predisposition

assessment each year. In Canada, predisposition assessments

address issues such as fitness to stand trial, treatability

and dangerousness of the offender. These assessments

typically include psychometric and clinical appraisal of the

offender, and aid the court in determining disposition.

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Again, the instrument most often employed in psychometric

assessments of sex offenders is the MMPI, which suggests a

second reason for evaluating the MMPI in the context of sex

offenders. The following is a review of the literature

relating the MMPI to sex offenders. Hereafter, WMPI

researchgg refers specifically to MMPI research with sex

offenders.

MMPI research with sex offenders

Early attempts to differentiate subgroups of sex

offenders, or sex offenders from non-sex offenders using

MMPI profiles, employed empirically based subscales such as

the Sexual Deviation scale (Marsh, Hilliard, & Leichti,

1955), the Pedophilic scale (Toobert, Bartelme, & James,

1959), and the Aggravated Sex scale (Panton, 1970).

However, these scales are typified by poor criterion related

validity, and as might be expected from sample specific

measures, rarely cross-validate.

For example, Peek and Storm (1956) and Wattron (1958)

failed to validate the Sexual ~eviation scale (Marsh et al.,

1955), prompting Wattron (1958) to conclude that the

I1instrument is of no practical value in discriminating

between sex offenders and other type felons in correctional

settings." (p.16). The Sexual Deviation scale appears to be

more a measure of gross maladjustment (Wattron, 1958) and

general abnormality (Peek & Storm, 1956) than of deviant

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sexual trends.

Butcher and Tellegen (1978) discuss several problems

with the development and use of MMPI subscales. They

conclude that subscales often Itprove to be largely redundant

alternative versions of existing scales, although sometimes

of poorer qua1ity.I' (p.622). Thus, more recent research

relating the MMPI to sex offenders has focused primarily on

the ten standard clinical and three validity MMPI scales.

Unfortunately, this shift from subscales to standard scales

has not produced a clearer picture of the personality

characteristics of sex offenders. Indeed, the more recent

research has produced an inconsistent and ultimately

confusing welter of results. In the sections to follow I

argue that much of this confusion arises from poor design

and methodological variations across studies. The following

issues will be discussed:

1. Samples selection

2. Definition of groups

3. Definition of MMPI protocol validity

4. Statistical analyses of MMPI profiles

5 . MMPI scores reported.

Finally, MMPI results will be discussed in the light of

these methodological problems, and the Millon Clinical

Multiaxial Inventory will be introduced.

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1. Sam~le selection

The samples used in sex offender studies have varied on

several dimensions beyond type of offense. For example,

some subjects were incarcereted in prison (Carroll & Fuller,

1971; Panton, 1978; Panton, 1979), whereas others were

remanded to a psychiatric unit for pretrial assessment

(Armentrout & Hauer, 1978; Quinsey, Arnold, & Preusse,

1980). Moreover, these settings vary as to whether they are

maximum security (Quinsey et al., 1980) or medium security

(Carroll & Fuller, 1971).

Subjects also have been selected from a psychiatric

hospital ward for the criminally insane (Anderson, Kunce, &

Rich, 1979), a state hospital in-patient unit (Hall, Maiuro,

Vitaliano, & Proctor, 1986; Hall, 1989), and an out-patient

family treatment program (Scott & Stone, 1986). Finally,

subjects vary according to stage of proceedings; some have

been convicted for their offense (Carroll & Fuller, 1971;

Groff C Hubble, 1978; and Scott & Stone, 1986), some were

referred by the courts for a presentencing evaluation after

conviction (Erickson, Luxenberg, Walbek, & Seely, 1987;

McCreary, 1975a, McCreary, 1975b), and others were referred

to various settings for pretrial assessment (Armentrout &

Hauer, 1978; Quinsey et al., 1980; Rader, 1977). Obviously,

these samples would be expected to differ on a wide variety

of characteristics besides type of sex offense, each of

which could affect MMPI profiles. Thus, one reason why

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MMPI-sex offender results may be so inconsistent is because

sex offense and other sample characteristics are confounded

across studies.

2. Definition of srouw

Itsex offensen is an umbrella term referring to a wide

range of behaviors. Consequently, sex offenders represent a

heterogeneous group that varies in offender, offense, and

victim characteristics. Given the enormity of this

variation, any single study addressing offender personality

characteristics would be hard pressed to obtain

representative samples, and once obtained, to find enough

individuals in each combination of offender, offense, and

victim characteristics to reliably differentiate them.

This has had two general effects on studies using the

MMPI to differentiate or classify sex offenders. The first,

and perhaps most problematic of these, is that groups are

categorized along a single dimension with the remaining

dimensions left uncontrolled and free to undermine the

internal validity of the results. The second is that many

studies use a small number of narrowly defined groups. This

second problem is less an issue at the level of a single

study, but hinders interpretation when the narrowly defined

groups vary across studies. As discussed below, such

across-study variation in offender characteristics is the

rule rather than the exception in MMPI research.

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The notion that sex offenders make up a heterogeneous

group is not new, and has been proposed by several

researchers (e.g., Armentrout & Hauer, 1980; Hall, 1989;

Rader, 1977). Nevzrtheless, studies (primarily earlier

studies) have combined sex offenders that have committed a

variety of crimes (e.g., rape, incest, indecent exposure)

into one group, and compared it to groups of non-sex

offenders (Carroll & Fuller, 1971; Hartmann, 1967; Swenson &

Grimes, 1958). These early studies yielded few significant

findings. Also, MMPI profiles of heterogeneous groups of

sex offenders have not been found to differ significantly

from profiles of other criminal groups (e.g. Panton, 1978).

Thus, studies that have conbined various types of sex

offenders into one group, and attempted to differentiate

them from groups of non-sex offenders on the basis of MMPI ,

profiles, have, for the most part, been unsuccessful.

More recent studies employing the MMPI to differentiate

types of sex offenders have used more narrowly defined

groups and attempted to better control for competing

differences among groups. However, this refinement has lead

to a new problem, namely that virtually no two studies use

the same groups for comparison. Rather than replicating and

expanding previous studies, each study represents a radical

departure from the studies before it, in terms of group

definition. Table 1 helps to illustrate the numerous

different between the groups selected for MMPI research

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across studies.

The major difficulty that arises from the using

numerous group types across studies is that direct

comparison of results is often confusing and sometimes

impossible. his is especially true when the issue of

heterogeneous sample selection is also considered.

MMPI studies often have selectively chosen specific

dimensions of offender, offense, or victim characteristics

for investigation. Typically, groups are defined on the

basis of one of these, followed by a comparison of

personality characteristics derived from each group's MMPI

profile configuration. For example, several studies have

compared offense variables such as rapists of adults,

rapists of children, and nonrapist sex offenders (Armentrout

& Hauer, 1978), murderers, arsonists, property offenders,

rapists, and child molesters (Quinsey et al., 1980),

exposers, assaulters, and rapists (Rader, 1977), incestuous

offenders and child molesters (Panton, 1979), and rapists of

adults, rapists of children, and non-violent child molesters

(Panton, 1978). Victim characteristics used in MMPI studies

have included age of victim (Groff & Hubble, 1984) and sex

of victim (Langevin et al., 1978), and offender

characteristics have included number of prior arrests

(McCreary, 1975a; McCreary, 1975b), sexual orientation

(Langevin et al., 1978), and relationship of offender to

victim (Groff & Hubble, 1984; Scott & Stone, 1986).

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Table 1. Different Groups Used in MMPI Research with Sex Offenders

Study Categorization of Groups

Armentrout & Hauer (1978) Rapists of children, rapists of adults, non-rapist sex offenders

Carroll & Fuller (1971) Non-violent, violent, sexual

Erickson, et al. (1987) Rapists, child molesters, incest offenders, first time offenders, sex offender recidivists, non-sex offender recidivists

Groff & Hubble (1984)

Langevin, et al. (1978)

5

McCreary (1975a)

Incestuous fathers and incestuous stepfathers who abuse younger versus older daughters/stepdaughters

Homosexuals, transsexuals, bisexuals, homosexual pedophiles, heterosexual pedophiles, incestuous cases, exhibitionists, multiple deviants

Men convicted of indecent exposure'with no prior arrests, 1-5 prior arrests, more than 5 prior arrests

McCreary (1975b) Child molesters with no prior arrests, child molesters with one or more prior arrests

Rapists of adults, rapists of children, non-violent sexual molesters of children

Incest with daughters, molesters of female children

Quinsey et al. (1980) Murderers of family, murderers of non-family, arsonists, rapists, child

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Rader (1977)

molesters, property crimes

Exposers, assaulters, rapists

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It appears therefore that most of the more recent MMPI

research has compared group selected exclusively on the

basis of either offense type, victim characteristics, or

offender characteristics rather than systematically

including or controlling for more than one dimension. Hall

et al. (1986) and Hall (1989) criticize previous MMPI-sex

offender research for examining single variables, such as

offense variables, without controlling for or considering

variables, such as victim and offender variables, that

confound and interact.

One of the earliest studies to compare several

dimensions of sex offenders in relation to personality

factors was Langevin et al. (1978). In this study each of

their eight groups were categorized as preferring mature vs.

immature partners (age preference), males or females (sex

preference), and intercourse, rape, exposing, etc. (response

preference). However, this study's external validity is

compromised in that two of their groups (homosexual and

bisexual males preferring adult partners) would no longer be

considered relevant for studies of sex offenders, as they

are not presently considered anomalous characteristics

(American Psychiatric ~ssociation, 1987).

Hall et al. (1986) and Hall (1989) have perhaps

employed the most sophisticated method of group assignment

to date. These studies examined the utility of the MMPI in

differentiating between offenders who has assaulted male vs.

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female victims, committed incestual vs. nonincestual

offenses, used physical force vs. nonphysical coercion,

raped vs.molested their victims, and assaulted older vs.

younger victims. Thus offender (relationship of offender to

victim), offense (type of coercion, rape vs. molestation),

and victim (sex, age) characteristics were simultaneously

compared for men who had sexually assaulted children. In

many previous studies, men who had sexually assaulted

children were defined as a homogeneous group and compared to

other groups exclusively defined by offense type, such as

rapists of adults, non-sex affenders, etc. (e.g. McCreary

1975a; Armentrout & Hauer, 1978; Quinsey et al., 1980).

Thus, this classification scheme (Hall et al., 1986; Hall,

1989) represents an improvement over the ones chosen in

previous MMPI research with sex offenders. However, only

one offender characteristic (relationship to victim) was

investigated.

Erickson, Luxenberg, Walbek, and Seely (1987) have also

emphasized the heterogeneity of personality characteristics

of sex offenders, and criticized previous research for

stereotypic descriptions of sex offenders, and the liberal

application of the article "the1' to describe the rapist, the

child molester, etc. This study (Erickson et al., 1987)

included more specific offender characteristics than any

previous MMPI studies. MMPI 2-point codes were collated

according to whether cases were intrafamilial or

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extrafamilial, whether victims were adults or children, male

or female, whether subjects were recidivists or first time

offenders, and whether subjects were chemically dependent.

Recidivists were further divided as to whether their

previous offenses were sexual or nonsexual. Thus, both

offender and victim characteristics were investigated.

Unfortunately, offense characteristics, such as rape versus

molestation, were not included.

3. Definition of MMPI protocol validity

Studies relating the MMPI to sex offenders also differ

according to their definition of MMPI protocol validity. As

a result, different studies exclude different types of

offenders for different reasons, thus jeopardizing their

comparability. Several studies neglected to address 3

protocol validity (Anderson et al., 1979; Armentrout &

Hauer, 1978; Carroll & Fuller, 1971; Langevin, Paitich,

Freeman, Mann, & Handy, 1978). McCreary (1975a) omitted six

subjects on the basis of invalid profiles but did not define

the criteria for doing so. Some studies omitted subjects

solely on the basis of raw F scores above a particular

number (Quinsey et al., 1980; Rader, 1977). Still others

apply more than one criteria, for example L < 70, F < 100, K

< 70 (Erickson et al., 1987); L < 70, F < 85, K < 70

(Panton, 1979). An additional validity criterion method

used in some studies was the F-K index employing various raw

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score cutoffs (Groff & Hubble, 1984; Hall et al, 1986).

Perhaps the most stringent criterion used for

eliminating invalid profiles in MMPI studies was that

employed by Hall et al. (1986). The criterion used in this

study excluded profiles with a raw score of F-K < 11 and a T

score of L < 70. Using this criterion 434 subjects, or two

thirds of their original sample, were deleted from analysis!

However, in a replication and extension of Hall et al.

(1986), Hall (1989) did not exclude subjects based on

~~invalidw profiles, and pointed out that Graham (1987, cited

in Hall, 1989) suggested that valid MMPI profiles may

mistakenly be discarded when employing overly conservative

approaches to MMPI validity.

Anderson et al. (1979) analyzed a group of 92 sex

offenders by a Q-type factor analysis and found that a

particular MMPI personality type was characterized by a high

F score, along with an elevated Sc score. Consequently,

they cautioned against discounting MMPI profiles due to

relatively high F scores.

Gynther (1962) found a significant relationship between

sexual crimes and high F scores. This, in addition to

Anderson et al.sf (1979) results, indicates that it may be

important to employ a more liberal approach in determining

MMPI profile validity in a sex offender population. Gearing

(1979) emphasizes that an F scale elevation above 80 (T

score) may actually be valid, especially with a prison

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population. Gearing (1979) suggests that a good deal of

MMPI research with prisoners in general is compromised by an

I1overly rigid application of conventional validity criterial1

(p. 941). He therefore recommends that random profiles only

be discarded until further research produces dependable

indicators of faked prisoner profiles.

4. Statistical analysis of MMPI profiles

Most previous research with sex offenders has employed

univariate statistical techniques for data analyses (Carol1

& Fuller, 1971; Erickson et al., 1987; Groff & Hubble, 1984;

McCreary, 1975a; McCreary, 1975b; Panton, 1978; Panton,

1979; Rader, 1977; Scott & Stone, 1986). Several studies

used multiple t-tests without correcting for Type I error

(McCreary, 1975a; McCreary, 1975b; Panton, 1978; Panton, ,

1979; Rader, 1977), thus increasing the probability of

chance differences across groups being treated as genuine.

Occasionally the use of multiple t tests and F tests were

combined with a reduction of alpha to .O1 (Scott t Stone,

1986; Hall et al., 1986). Armentrout & Hauer (1978) did not

report the statistical methods used to analyze their data.

Even where more appropriate multivariate procedures are

used (e.g., MANOVA or discriminant function analysis) two

problems remain. First, the ratio of variables to number of

subjects is rarely sufficient to provide adequate

statistical power. ~iven the rule of thumb ratio of ten

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subjects per variable, a minimum of 130 subjects would be

required to analyze the 13 MNPI scales alone, and an

additional 10 subjects for every additional independent

variable. Of the MMPI studies reviewed, only four meet this

requirement (Carol1 & Fuller, 1971; Langevin et al., 1978;

Hall et al., 1986; Erickson et al., 1987). Second, the

scales of the MMPI are moderately intercorrelated, and

highly multiply correlated, leaving little unique variance

for any single scale to discriminate offender types.

One way in which these problems can be circumvented is

to component analyze the MMPI scales into orthogonal latent

constructs, and then use the reduced number of component

scores for analyses. This would increase the power of

statistical analyses and alleviate the unique versus common

variance problem. Unfortunately, the cost in using this

procedure is limited interpretability of profiles at the

individual level, thereby reducing the clinical or practical

utility of results. However, given the numerous benefits of

component analysis for the purposes of the present study,

interpretability at the individual level was viewed as an

acceptable cost.

5 . MMPI scores reported

MMPI studies with sex offenders vary considerably in

which MMPI scores are reported. Frequently, standard MMPI

scale group means are reported in isolation (Carroll &

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Fuller, 1971; McCreary, 1975a; McCreary, 1975b; Panton,

1978; Panton, 1979). Group means can be misleading because

they do not necessarily reflect modal profiles for a

particular sample (Butcher & Tellegen, 1978). In fact, Hall

et al. (1986) found that the Welsh code for their entire

sample did not correspond to any one individual profile in

that sample.

Rather than reporting group means, it is more useful to

report the frequencies or percentages of the different code

or profile types occurring in a sample. At a minimum, the

number or percentage of subjects in each group with a T

score above 70 should be reported for each of the standard

MMPI scales (for examples refer to Hall et al., 1986;

Langevin et al., 1978; Quinszy et al., 1980).

Ideally, the data should be presented to convey as much

information as possible. This would include reporting the

frequencies or percentages of order-independent two point

Welsh codes (e.g. scales 3-4 or 4-3 are elevated), of the

frequencies or percentages of subjects in each group with a

T > 70 for each of the clinical scales, in addition to the

group means. This would facilitate comparison of results

across studies.

MMPI results in sex offender studies

Combined, the methodological problems discussed above

make MMPI/sex offender research results difficult to compare

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and interpret. Therefore, rather than reporting an

extensive list of MMPI/sex offender research findings, the

following discussion will focus on the general findings,

with particular reference to the methodological issues '

previously addressed.

Despite wide variations in methodological procedures,

studies relating MMPI profiles to sex offenders have tended

to converge on the K-corrected 4-8/8-4 profile as the mean

profile for sex offenders in general (Armentrout & Hauer,

1978; Hall et al., 1986; Panton, 1958; Panton, 1978; Quinsey

et al., 1980; Rader, 1977; Pwenson & Grimes, 1958). The 4-

8/8-4 profile was reported for various sex offense

categories including rapists of children (Armentrout &

Hauer, 1978; Panton, 1978), rapists of adults (Armentrout &

Hauer, 1978; Panton, 1978; Rader, 1977), child molesters

(Erickson et al., 1987; Hall et al., 1986; McCreary, 1975a),

exposers (McCreary, 1975b; Rader, 1977), and multiple

deviants (~angevin et al., 1978).

However, although the 4-8/8-4 profile appears to be the

most frequently occurring profile in various groups of sex

offenders, it is sometimes the case that relatively few

individuals produce this profile. For example, Hall et al.

(1986) reported that although the modal profile for their

sample was 4-8/8-4, only 7.2 % of their subjects exhibited

this profile. Armentrout & Hauer (1978) found that although

4-8/8-4 was the modal profile for their sample of rapists,

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it occurred for only three of the 17 individuals. As

previously mentioned, very often MMPI studies report group

means on the standard MMPI scales without reporting the

frequency or percentages of individuals obtaining scale

elevations or 2-point codes.

Studies have also frequently reported finding no

significant differences of MMPI profiles between various

groups of sex offenders. Quinsey et al. (1980) compared

several groups with a wide range of offense characteristics,

including rapists and child molesters, and found that Itthe

extreme similarity of the offender groupst MMPI scores is

the most salient result of this studyw (p. 414). Groff and

Hubble (1984) found no systematic MMPI profile differences

between incestuous fathers and stepfathers. Armentrout and

Hauer (1978) reported that rapists of adults and non-rapist >

sex offenders bothexhibited the same modal MMPI profile (4-

8/8-4). Hall et al. (1986) and Hall (1989) concluded that

sex offenders are not characterized by a specific MMPI

profile configuration. Erickson et al. (1987) reported that

their findings "do not support descriptions of any MMPI

profile as typical of any sort of sex offenderu (p. 569).

Several studies have also found that sex offender MMPI

profiles do not differ significantly from those of offenders

convicted of other crimes (Hartmann, 1967; Perdue & Lester,

1972; Persons & Marks, 1971). Erickson et al. (1987) found

that MMPI profiles of sex offenders were remarkably similar

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to those of arsonists, murderers, and property offenders.

Quinsey et al. (1980) found no significant differences

between individuals convicted of sexual offenses versus

those convicted of other offenses. Quinsey et al. (1980)

also found that the mean K-corrected MMPI clinical scales

for their total sample correlated highly with samples from

other studies of hospital narcotics addicts (r=.91), heroin-

using male veterans (r=.85), and personality disordered male

veterans (r=. 85) . Finally, several studies reported that various sex

offender groups had essentially normal profiles. Carroll &

Fuller (1971) found that the MMPI profiles of violent and

sex offender groups did not differ significantly from the

normal, general, non-incarcerated population. Rader (1977)

reported that exhibitionists had normal MMPI profiles. >

Langevin et al. (1978) noted that I1most subjects have T

scores below 70, that is, they score within normal limitsM

(p.232). Anderson et al. (1979) conclude after a review of

MMPI studies that MMPI profiles of sex offenders reflected

minimum psychopathology. Scott and Stone (1986) found that

their groups of incestuous fathers and stepfathers produced

mean profiles in the normal range.

Thus, it appears that MMPI research with sex offenders

has produced equivocal results to date. In general, sex

offenders most often exhibit profiles that do not

differentiate them from other offender populations, and

20

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indeed frequently produce clinically normal profiles.

Undoubtedly part of the problem with interpreting the

results of studies stems from the methodological issues

discussed earlier. However, even studies that are more

methodologically refined (e.g. Hall et al., 1986; Hall,

1989; Erickson et al., 1987) produced negative results.

Indeed, it appears that when attempts are made to control

for variables that may confound or interact, the MMPI

becomes less useful in discriminating various types of sex

offenders.

A second potential reason for equivocal MMPI results is

the relative infrequency among sex offenders of the very

clinical syndromes (Axis I of the DSM-111) best captured by

the MMPI (Finkelhor, 1978; Maisch, 1972; Meiselman, 1978).

For example, Groff & Hubble (1984) found that nearly half of

their sample of incestuous offenders fell within Goldberg's

(1972) sociopathic category, indicating a variety of

personality disorders, and conclude that this finding

suggests that incestuous offenders "were more likely to

exhibit characteristics of personality disorders rather than

neurotic or psychotic symptoms.It (page 472). Thus, sex

offenders may be more likely to harbour personality

disorders (i.e., Axis I1 of the DSM-111), and attempts to

assess them should use an instrument that is more sensitive

to those disorders. One such instrument is the Millon

Clinical Multiaxial Inventory, a self-report measure

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specifically designed to assess both Axis 1 and personality

disorders. Thus, the centrr-1 thesis of the present research

is that the MCMI will better capture the psychological

characteristics of sex offerders (defined simultaneously

along offense, offender, and victim dimensions) than will

the MMPI. The next section will describe the MCMI and end

with the specific goals of the present study.

The Millon Clinical Multiaxial Inventorv

The MCMI is a relatively recent (Millon, 1977) self-

report inventory, and is a direct operationalization of

Millon's theoretical system and taxonomy (Millon, 1969,

1981). The MCMI includes 8 basic personality styles

(schizoid, avoidant, dependent, histrionic, narcissistic,

antisocial, compulsive, passive-aggressive), 3 pathological !

personality syndromes (schizotypal, borderline, paranoid), 6

symptom disorders scales of moderate severity (anxiety,

somatoform, hypomanic, dysthymia, alcohol abuse, drug abuse)

3 symptom disorder scales of extreme severity (psychotic

thinking, psychotic depression, psychotic delusions), plus 2

additional correction scales which provide a means to \

identify and adjust possible test taking distortion

(Mitchell, 1985) . A major advantage of the MCMI over the MMPI is its

relationship to the current diagnostic nomenclature

(Widiger, 1985). The MMPI scales and profile codes are

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based on the antiquated DSM-I. Current research and

clinical practice has shifted from an emphasis in the

diagnosis of psychiatric syndromes (DSM-111, Axis I), to the

diagnosis of personality disorders (DSM-111, Axis 11). The

MCMI is the self-report inventory most closely related to

Axis I1 diagnoses (Widiger, 1985).

More recently, however, Widiger, Williams, Spitzer, &

Frances (1985) question the use of the MCMIts ability to

measure DSM-I11 Axis I1 disorders. They point out that

there has been no published empirical research addressing

the relationship between the MCMI and DSM-111. Millon

(1985b), in response to ~idiger et a1.I~ (1985)

implications, argues that the I1MCMI was never intended to be

a measure of DSM-111" (p. 379), but was developed to be as

consonant as possible with DSM-I11 classifications.

Millon (1985b, 1986) further argues that his

borderline, schizotypal, and narcissistic personality

syndromes are conceptually equivalent to the corresponding

DSM-I11 categories. The MCMI and DSM-I11 correspond only to

the extent that the conceptual and clinical categories of

Millon's theory and the DSM-I11 overlap (Millon, 1986).

Indeed, Widiger & Sanderson (1987) in a study using the MCMI

with 53 psychiatric hospital inpatients, found better

convergent validity for the DSM-I11 disorders that were

consistent with Millonts typology (avoidant and dependent

personality disorders) than for disorders that were

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inconsistent (antisocial and passive-aggressive).

There have been relatively few empirical studies using

the MCMI to date. The first study to investigate the

relationship of the MCMI to an offender sample was conducted

very recently by McCormack, Barnett, & Wallbrown (1989).

One thousand two hundred MCMI offender profiles were

randomly divided into two groups of 600, and subjected to a

principal components factor analysis. Successful cross

validation was achieved, as the four factors derived in both

groups were similar.

Purpose of present study

The purposes of the present study are:

1. To categorize sex offenders according to more offender,

offense, and victim characteristics than previous MMPI

studies.

2. to compare the predictive validity of the MMPI and MCMI

with respect to offender, offense, and victim

characteristics.

3. to evaluate the common and unique aspects of offender

characteristics, the MMPI, the MCMI for predicting offense

and victim characteristics.

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CHAPTER 11

METHOD

Subj ects

Subjects were 127 male sex offenders who had been

referred to Forensic Psychiatric Services, Victoria, for

predisposition assessment or treatment between July 1, 1986

and December 31, 1989. All those subjects who had completed

nonrandom MMPIts (~earing, 1979) and MCMI1s, and had a grade

six or higher level of education (Hathaway & McKinley, 1967)

were included in the sample. The Carelessness scale

(Greene, 1978) was used to determine random MMPI profiles,

employing a cutoff score of five of the 12 item pairs

(Greene, 1980), which would indicate that the subject was

contradicting himself to the extent that responses were

random, or misunderstood. An MCMI Validity Index score of

zero indicated a nonrandom profile (Millon, 1983).

Procedure

Offense history data were obtained from the clinical

files of sex offenders at Forensic Psychiatric Services

outpatient clinic. Those subjects who completed nonrandom

MMPI Group form and MCMI between July, 1986 December, 1989

were included for analyses. In addition, a description of

the offender, offense, and victim characteristics used for

analyses follows. victim and offense characteristics were

combined for statistical analyses and are jointly termed

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offense variables. It should be stressed that this sample

of sex offenders is somewhat posively skewed with respect to

age of victim, i.e., there was a relatively high proportion

~f offenses against individrals under age 16. Also, because

the subjects were attending an outpatient clinic, by

definition the offenses were not serious enough to warrant

remand in custody, and the subjects were not incarcerated at

the time of assessment.

Offender Variables:

Age in years at initial offense - 11-20, 21-30, 31-40, 41-70 Employment - unemployed, retired, skilled labour (professional, sales, entrepreneur), unskilled labour

Education - high school graduate or higher, grade eleven or less

Marital status at the time of offense - single, divorced or separated, married or cohabitating, remarried

History of physical!abuse - history versus no history of physical abuse

History of sexual abuse - history versus no history of sexual abuse

History of criminal offenses - presence versus absence of criminal record

Substance abuse - drugs (narcotics, prescription, or one of these in combination with alcohol), alcohol, no substance abuse

Offense and Victim Characteristics:

Number of victims - one victim versus more than one victim Relationship of offender to victim - intrafamilial (biological father, step-father, uncle, grandfather, sibling) versus extrafamilial (friend, stranger)

Type of offense - relatively more serious (digital, vaginal,

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or anal penetration, oral sey: to or by victim), relatively less serious (hands off, e.g:, exposing, obscene phone calls; fondling or masturbation to or by victim)

Highest number of repeats with any given victim - once only per victim, 2-19 incidents, 20 or more incidents

Youngest age of any given victim at the time of the first offense -ten years or younger, eleven years or older

Other variables were initially coded but excluded due

to restricted range, defined as 70 percent or more subjects

belonging to any one category. These included sexual

orientation (78% heterosexual, 8% homosexual, 5% bisexual),

sex of victim (74% female, 13% male, 13% both), and physical

coercion or aggression involved in offense (71% no, 20% yes,

9% unknown). In addition, marital status of offenders'

parents was coded but was excluded when preliminary analyses

indicated that it was unrelated either singly or jointly to

any other variables:

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Outline of Statistical Analyses

Two classes of analyses were used to evaluate the data.

The first used procedures typical of previous research

investigating the MMPI profiles of sex offenders, but

followed the advise of ~earing (1979) to investigate several

different quantifications of MMPI protocols. Of course,

both the MMPI and MCMI were used and compared. Examples of

the first class of analyses include comparison of high-point

profiles, order independent conjoint 2-point codes, and

group mean profiles.

The second class of analyses focused on the overall

relations among MMPI, MCMI, offender, and offense variables

and proceeded as follows:

1. Data reduction. The offender and offense variables were

reduced using cluster analysis, and the MMPI and MCMI scales

were component analyzed.

2. Analvsis of airw wise relations. Each pair of variable

sets was analyzed using MANOVA, discriminant function, or

canonical analysis where appropriate. Examples of pairwise

relations include offender/offense relations,

personality/offender relations, and personality/offense

relations. These analyses might seem redundant given step 3

of the analysis described below in which multiple-set

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relations are investigated. They were included for two

reasons. First, previous research on sex offenders has

investigated pairwise set relations (e.g., MMPI/offender

relations) and could be compared with the current results

only if similar procedures were used here. The second

reason was that the results of multiple-set analysis are

easier to interpret if the simpler pairwise relations are

understood, much like partial correlations are more

interpretable if lower-order correlations are understood

first.

3. Multiple-set relations. In this analysis offender

clusters and personality components were considered as sets

of predictor variables and offense clusters as a set of

criterion variables. Multiple set correlation (see Cohen,

1982) was used to evaluate the common and unique aspects of 1

each predictor set in "e~plaining~~ the criterion set. More

is said about this technique below.

Analvsis of 2-point codes and mean profiles

The following is a discussion of MMPI and MCMI results

analyzed in the same manner as in most previous sex offender

research. The mean MMPI 2-point code for the entire sample

was 2-4/4-2, which was also the modal 2-point code. The

MCMI mean 2-point code for the total sample was 3-A/A-3,

although the modal profile for the sample was D-A/A-D. On

both instruments the mean 2-point codes were not clinically

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elevated. Table 2 presents the MMPI and MCMI means for each

scale for the total sample.

Although 2-4/4-2 was the mean and modal MMPI profile

for the total sample, only eight subjects, or 6.3% of the

sample, exhibited this profile. Table 3 illustrates the

frequencies and percentages of subjects obtaining the most

common order-independent 2-point codes occurring in the

present sample. Clearly the sample produced heterogeneous

MMPI profiles, indicating that no particular 2-point code

captures the sex offenders in this sample. Scales 2 and 4

were also the most frequently elevated scales in the sample.

Table 4 presents the frequency and percentage of subjects

obtaining a T-score 70 or higher on each of the MMPI scales.

The MCMI order-independent 2-point codes and single

scale elevations are presented in Table 5. The D-A/A-D 3

(Anxiety and Dysthymic) scales comprised the 2-point codes

for 21 subjects, or 16.5 percent of the total sample.

Twenty percent, or 25 subjects, had scale 3

(dependent/submissive) elevated above baserate (BR) of 75

and as their highest scale elevation. There were 10

subjects (8%) whose profiles yielded no scale elevations

above a BR of 75, versus 19 subjects (15%) with MMPI

profiles with all scales below a t-score of 70. Table 6

presents the frequency and percentage of subjects obtaining

a BR score of 75 or higher on each of the MCMI scales.

The three most frequently occurring order-independent

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Table 2. MMPI and MCMI Means for Total Sample

MMPI Scale Mean MCMI Scale Mean

Table 3. Order Independent IqYlPI 2-Point Codes

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T a b l e 4 . Frequency and Percentage of subjects in Total Sample with MMPI T-scores >69

Scale N %

T a b l e 5. Order Independent MCMI 2-Point Codes and Highest single Scale lev at ions (above BR 75)

Scale N %

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codes on the MCMI account for 31.5 percent of the total

sample, whereas the three mast frequently occurring order-

independent MMPI codes only account for 16.5 percent of the

sample. Thus, it appears that the sample is more

homogeneous on the basis of MCMI than on MMPI profiles.

Table 6 shows the frequency and respective percents of

subjects with a BR above 74 on each MCMI scale.

As discussed in the ~ntroduction, previous MMPI studies

with sex offenders frequently employed multiple t-tests to

compare the mean MMPI scores for each group of interest,

resulting in an increase of Type I error. In the present

study there are 13 offender/offense variables and 33

MMPI/MCMI personality variables. Therefore, rather than

resorting to a confusing and undoubtedly erroneous welter of

univariate analyses the data were first reduced and then )

analyzed using to multivariate procedures.

Data reduction -- Offender characteristics Table 7 presents a table of contingency coefficients,

which highlights significant correlations among the offender

characteristics. The following is a list of offender

variable abbreviations and their explanations:

AGE - Offender age at initial sexual offense EDUC - Education level EMPLOY - Employment MARITAL - Marital status at time of offense PHYSAB - History of previous physical abuse SEXAB - History of previous sexual abuse SUBAB - Substance abuse CRIM - Previous criminal record

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Table 6. Frequency and Percentage of Subjects in Total Sample with MCMI BR Scores > 75

S c a l e N %

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Table 7. Contingency coefficients Among Offender Variables

AGE EDUC EMPLOY MARITAL PHYSAB SEXAB SUBAB CRIM AGE 1.00

EDUC .05* 1.00 EMPLOY .39*** .19 1.00

MARITAL . 4 5 . 2 2 .30 1.00 PHYSAB . 2 6 .11 . 1 8 .25 LOO**

SEXAB .19 .17 .12 .31* 1.00 SUBAB .28 .37 .20

CRIM .17 .09 .24 .12 *26** .32 .13 1.00

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Clearly one would not expect that sex offenders

represent a homogeneous group -- a point made throughout the sex offender literature. Therefore, the possibility that

the current sample of offenders could be grouped into types

that display systematic differences in offender

characteristics was investigated using cluster analysis.

Unfortunately, there is no universal agreement on the "bestu

clustering algorithm, so several were attempted including

hierarchical and partitioning methods as well as a recently

designed nonparametric procedure (Brinkhurst, 1988). These

analyses converged on a three cluster solution in which

groups differed in age at time of initial offense,

employment, and marital status at time of offense. The

remaining offender variables of education, history of

physical and sexual abuse, and criminal record, did not I

differentiate the initial three groups and were submitted to

a second cluster analysis. The results produced a two

cluster solution. A description of the results of these

analyses is presented below.

Three cluster solution

The first cluster (N = 44) is the youngest group of the

three, and will therefore be referred to as the "young

groupat. Individuals who comprise this cluster are likely to

be 30 or younger, employed at unskilled labour, 'and single.

The second cluster (N = 48) are primarily unemployed (the

"unemployed groupw) and are most likely to be between the

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ages of 31-40. They are equally likely to be divorced,

married, or single. The third cluster (N =35), and oldest

of the three groups were most likely employed as skilled

laborers, and married ("married groupI1 ) . Two cluster solution

Offenders that comprise the first cluster (N = 57) have

a relatively unremarkable history in that they are likely to

have no history of physical or sexual abuse, and no previous

criminal rec,ord. On the other hand, offenders in the second

cluster (N = 37) do have a remarkable history in that they

were likely to have been physically and sexually abused, and

have a previous criminal record. They were also less

educated.

Data reduction -- Offense characteristics Table 8 presents a table of contingency coefficients

!

among the offense characteristics. The following is a list

of offense abbreviations and their explanations:

NOVIC - Number of victims FAMIL - F elation ship of offender to victim OFFNS - Type of offense REPEAT - Highest number of repeats with any victim AGEFIR - Youngest victimls age at time of first offense

Cluster analysis of these offense characteristics

produced a three cluster solution on which all of the

offense variables contributed to group differences. The

first cluster (N = 54), referred to as the "intrafamilial

group81, were more likely to offend against one intrafamilial

victim, the victim was typically 10 years old or younger,

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Table 8. Contingency coefficients Among Offense Variables

NOVIC FAMI L OFFNS REPEAT AGEFIR

NOVIC FAMIL OFFNS REPEAT AGEFIR 1. ooo** .403 1. OOO** .072 .469** 1. OOO** .I93 .509** .404** 1. OOO* .089 .354 .325 .295 1.000

Table 9. Contingency Coefficients Among Offense and Offender Variables

AGE EDUC EMPLOY MARITAL PHYSAB SEXAB SUBAB CRIM

NOVIC OFFNS REPEAT AGEFIR

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the number of repeat offenses was 20 or more, and the

offense was of a relatively more serious nature. The second

cluster (N = 52), or tfextrafamilial grouptt, were also likely

to have one victim only, but the victim was likely to be

extrafamilial, age 11 or older, and the offense was

typically one time only and of a relatively less serious

nature. The third cluster (N = 21), or "chronic groupu were

likely to offend against more than one victim, and the

victims tended to be both intrafamilial and extrafamilial.

The victims were ten or younger and there were typically

between 2-19 offense repeats per victim. The offenses

themselves were of a relatively more serious nature.

Data reduction - Personality variables MMPI T-scores were component analyzed followed by

normalized varimax rotation. The resulting four-factor 9

solution and corresponding variances accounted for are shown

in Table 10 where it can be seen that most of the scales are

factorially complex, i.e., they load on more than one

factor. In naming the factors (see below), labels were

chosen that reflected those scales that appeared to be

uniquely determined by the underlying construct.

Factor 1 -- Impulsive factor: This factor has its

maximal positive loading on Scale 9 (Ma), and reflects

energetic, impulsive, irritable, grandiose, and moody

characteristics.

Factor 2 -- Somatic factor: Maximal positive loadings

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Table 10. MMPI Rotated Factor Matrix (N=127)

Rotated Loadings 1 -. 440

.622 -.491 .017 .009 .022 .493

-.071 .482 .342 .600

*. 899 -.lo2

% of total 19.991 22.179 19.776 14.359 variance explained

* Loading greater than .80

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are found.on Scales 1 (Hs) and 3 (Hy), indicating a tendency

to develop somatic problems, and a demanding, complaining

personality style. Other characteristics of these scales

are attention-seeking, hostility, repression, denial,

manipulativeness, and lack of insight.

Factor 3 -- Introversi~n factor: This factor loaded

primarily on Scale 0 (Si), suggesting social introversion,

shyness, overcontrol, lethargy, and withdrawal.

Factor 4 -- Sensitivity factor: Scale 5 (Mf) is the

salient feature of this factor, indicating passivity,

sensitivity, and conflicts over heterosexual behaviour.

Interestingly, Scales 2 (D) and 4 (Pd), which comprise

the mean and modal 2-point code for the total sample, did

not load exclusively on any one factor. In fact, Scale 4

loaded almost equally on three factors, indicating that 1

Scale 4 characterizes several features of the criminal

population in general, such as impulsivity, apathy, and

social maladjustment. Also, there may be a more complex

relationship of this scale to other MMPI scales than has

been hypothesized in previous research. This may partially

explain the inconsistent results in previous MMPI studies

with sex offenders.

Table 11 presents the corresponding component analysis

of the MCMI scales.

Factor 1 -- Bizarre/withdrawn: this factor is bipolar with the positive pole defined by loadings on Psychotic

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Table 11. MCMI Rotated Factor Matrix (N=127)

Rotated Loadings

Schizoid Avoidant Dependent Histrionic Narcissistic Antisocial Compulsive Passive-Aggressive Schizotypal Borderline Paranoid Anxiety Somatoform Hypomanic Dysthymic Alcohol Abuse Drug Abuse Psychotic Thinking Psychotic Depression Psychotic Delusions

Percent of Total 27.502 ' !

Variance Explained

Table 12. Pearson Correlation Matrix of MMPI and MCMI Factors

MMPI Factors 1 2 3 4

MCMI Factors 1 .421 .067 .709 .130 2 .661 -.204 -.342 -.010 3 .152 .270 .I18 .270 4 .078 -.178 .019 -.236

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Depression (. 881) , Avoidant (. 848) , and Schizoid (. 818) . The negative pole includes loadings on compulsive (-.676)

and Narcissistic (-.526). Characteristics indicated by the

positive pole of this factor are behavioral apathy,

depression, interpersonal indifference, social isolation,

and alienated, devalued self image. The negative pole of

this factor involves an absence of motivation to conform to

the expectations of others, and of gregariousness/

sociability. Because this factor is bipolar, one would

expect those with low factor scores to evidence the opposite

of this factor's salient features. Therefore, individuals

scoring low on this factor would be expected to score high

on the Narcissistic and compulsive scales.

Factor 2 -- Sensation-seeking: This factor was defined ,

primarily by loadings on Drug Abuse (.868), Hypomanic

(.832), and ~istrionic (.804). The common themes of this

factor indicate impulsivity, emotional lability,

irritability, history of drug abuse, sociable/gregarious

self-image, immature stimulus seeking behaviour, and short-

sighted hedonism.

Factor 3 -- Somatoform: This factor is characterized

by positive loadings on Somatoform (.922), Anxiety (.882),

Borderline (.840), and Dysthymic (.832). Factor 3 is

bipolar, with its negative pole defined by a loading on

~ntisocial (-495). Individuals scoring high on this factor

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are likely to evidence anxiety, somatic tension, dysphoria,

massive interpersonal ambivalence, preoccupation with

feelings of discouragement or guilt, as well as a lack of

antisocial behaviour. Recall from the previous discussion

that 16.5% of the total sample evidenced ~nxiety and

Dysthymic 2-point codes, both of which load on this factor.

Factor 4 -- Paranoid: This factor was defined by

loadings on Psychotic Delusions (.869) and Paranoid (.776),

indicating paranoid behaviour and thinking with the

associated features of suspiciousness, and hostile acting

out.

Table 12 presents the Pearson correlations among the

MMPI and MCMI factors. Clearly there is overlap between

the two instruments even at the level of latent variables.

For example, MMPI factor 3 (Introversion) is correlated with ,

MCMI factor 1 (Bizarre/withdrawn), and MMPI factor 1

(Impulsive) is correlated with MCMI factor 2 (sensation-

seeking). MMPI factor 3 indicated social introversion,

shyness, lethargy, while MCMI factor 1 indicated behavioral

apathy, depression, interpersonal indifference, and social

isolation. MMPI factor 1 reflected energetic, impulsive,

irritable, grandiose, and moody characteristics. MCMI

factor 2 indicated impulsivity, emotional lability,

irritability, and sociable/gregarious self-image. The

characteristics described by the correlated factors on the

MMPI and MCMI appear to be behaviorally and cognitively

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similar.

Pairwise set relations -- Offender clusters and MMPI/MCMI factors

As previously stated, the offender and personality

(MMPI and MCMI factors) variables in this study are analyzed

and interpreted as independent variables or predictors. The

dependent variables, or criteria, are the offense variables.

Before exploring the relationships between the predictor and

criterion variables, relationships that exist between the

two groups of predictor variables will be investigated.

A factorial MANOVA was used to determine the

relationship of personality factors to the two and three

cluster solutions for the offender variables. The analysis

therefore consisted of testing the main effects and

interaction of the offender cluster solutions on

personality. This analysis yielded a significant main

effect for the two cluster solution of the offender

variables (Wilks' Lambda = .807, F(8,114) = 3.398, p <

.002). The offender group with an abusive history was

significantly more likely, on average, to have a higher

score on the MMPI Impulsive and Sensitivity factors

(F(1,121) = 14.337, p < .001; F(1,121) = 5.117, p < .03

respectively), and the MCMI Bizarre/withdrawn factor,

-F(1,121) = 10.991, p < .003). The three cluster solution

for the offender group, which produced the young,

unemployed, and married groups was not significantly related

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to the personality factors (Wilksf Lambda = .862, F (16,228)

= 1.100, p < .36). Additionally, the interaction between

the offender and personality variables was not significant

(Wilksf Lambda = .835, F(16,228) = 1.345, p < .17).

Pairwise set relations -- Offender and offense clusters This section and the one to follow will focus on the

relationship of each of the two predictor groups separately

with the offense, or criterion groups. The offender

clusters (predictors) and offense clusters (criterion) are

categorical variables leaving open several possibilities for

analysis (e.g., log-linear analysis, logit/probit analysis).

The approach chosen here was to code the offender and

offense clusters to produce meaningful single degree

contrasts among groups and then submit those contrasts to a

canonical correlation analysis. For example, the three

offense clusters were coded into two contrasts representing

(1) a comparison between the intrafamilial group and the

chronic group, and (2) a comparison between the extrafailial

group and the average of the intrafamilial and chronic

groups. Similarly, the offender cluster solutions were

coded to reflect the main effects of the two and three

cluster solutions and their interaction.

Neither the main effect for the two cluster solution of

offender variables (nonabusive versus abusive history) nor

the interaction were significant (p < .32 and p < .lo,

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respectively). The main effect of the three cluster

solution was significant (Wilkst Lambda = .769, F(4,240) =

8.428, p < .001) indicating that intrafamilial offenses

were, on average, more likely to be committed by individuals

belonging to the married cluster, whereas the chronic

offenses were more likely to be committed by individuals

belonging to the unemployed or young clusters (F(2) =

13.371, p < .001). Additionally, the extrafamilial offenses

were more likely to be committed by individuals belonging to

the young offender group, while the intrafamilial and

chronic offenses were more likely to be committed by the

married offender group (F(2) = 8.022, p < .001). Overall,

it appears that the young offender group is much more likely

to commit extrafamilail offenses, and the married group is

far more likely to commit intrafamilial offenses but rarely )

commit chronic or extrafamilial offenses.

Pairwise set relations -- Personality factors and offense clusters

The previous section described the relationship between

the offender predictors and the offense criterion. This

section will focus on the relationship between the

personality predictors and the offense criterion. First,

separate discriminant function analyses were carried out

using the 13 MMPI and 20 MCMI scale scores. These analyses

emulated the pairwise relations investigated in some

previous sex offender research. Next, the four MMPI and

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four MCMI factors were separately analyzed to see if they

could discriminate the contrast coded offense groups

described in the previous section. Finally, because the

MMPI and MCMI personality Eactors are intercorrelated (see

Table 12), a discriminant function analysis was done on each

of the two sets of personality factors with the other

partialled out. In other words, the MMPI was analyzed with

the MCMI partialled out, and vice versa for the MCMI, to

explore the unique relationship of each of these instruments

with the criterion, or offense groups.

The first part of these analyses, a discriminant

function analysis separately on all MMPI and MCMI scale

scores, produced no significant results (Wilks' Lambda =

.760, F(26,224) = 1.27, p < .20; Wilksl Lambda = .696,

F(40,210) = 1.043, p < .40, respectively). That this

analysis does not even approach significance can be

attributed in part to the fact that the ratio of subjects to

variables is too high, thereby diminishing the power of the

test. As discussed previously, this circumstance has been

the downfall of many previous MMPI studies with sex

offenders.

When the same analyses are done on the reduced number

of personality factors (the number of variables drops from

33 to 8) and with offense groups coded into meaningful

contrasts a different scenario emerges. The MMPI factors

remain not significantly related to the offense contrast

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codes (Wilkst Lambda = .90, F(8,242) = 1.638, p < .12).

However, the M C M I factors alone are significantly related

(wilksl Lambda = .874, F(8,242) = 2.115, p < .03), and both

discriminant functions are significant. The first

discriminant function, contrasting the intrafamilial and

chronic offense clusters was significantly discriminated by

the bizarre/withdrawn M C M I factor (Bartlett s x2 (8) = 16.56.

p < .03), with individuals committing the chronic offenses

obtaining a higher mean factor score on the

bizarre/withdrawn M C M I factor. The second discriminant

function indicated that individuals belonging to the

extrafamilial cluster were significantly more likely to

obtain a higher score on the M C M I paranoid factor than the

average of the intrafamilial and chronic groups (Bartlett

x2(3) = 7.741, p < .05).

The final analysis relating the personality factors and

the contrast coded offense clusters utilized a partialling

procedure. When the MMPI is analyzed with the M C M I

partialled out, a significant relationship emerges between

this instrument and the contrast coded offense clusters

(wilkst Lambda = .869, F(8,234) = 2.127, p < .05). One

discriminant function was significant, with the somatic MMPI

factor discriminating individuals belonging to the

intrafamilial offense cluster from those belonging to the

chronic offense cluster (Bartlett x2 (8) = 17.146, p < .O5) . The chronic offense group obtained, on average, a higher

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score on the somatic MMPI factor than did the intrafamilial

group.

A discriminant function analysis of the MCMI factors

with the MMPI factors partialled essentially replicated'the

results of the unpartialled analysis (wilksl Lambda = .844,

F(8,234) = 2.589, p < .01). Both discriminant functions

were significant (Bartlettfs x2 (8) = 20.76, p < .01; x2(3)

= 8.386, p < .03). Individuals belonging to the chronic

offense clusters were significantly more likely to obtain a

higher score on the MCMI Bizarre/withdrawn factor and a

lower score on MCMI Somatoform factor than those belonging

to the intrafamilial offense cluster. ~ndividuals belonging

to the extrafamilial offense cluster were again more likely

to obtain a higher score on the MCMI paranoid factor than

were the intrafamilial and chronic offense groups. >

~ultiple-set relation -- Offender, ~ersonalitv and offense variables

The focus of the analysis was to predict offense

characteristics (the criterion) from offender and

personality variables (the predictors). The procedure used

was multivariate set correlation (Cohen, 1982).

Conceptually, multiple-set correlation is a generalization

of multiple regression/correlation in which sets of

predictor variables are used to predict a set of criterion

variables rather than the usual relating of single

indicators of each. Set correlation provides indices of

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association analogous to those provided in MCR analysis, for

example the multivariate multiple correlation coefficient,

the multiple partial correlation and the multiple

semipartial correlation. Similarly there are multivariate

regression weights analogous to the partial regression

weights associated with standard multiple regression

procedures. This procedure provides numerous analytic

possibilities (see Cohen, 1982) and is ideal for the current

situation because it provides information concerning the

association between the common aspects of

predictor/criterion sets as well as between their unique

aspects. Details on computing F ratios and degrees of

freedom are given in Cohen, 1982, p. 318-322.

Many significance tests arise in multiple-set

correlation so protection of Type I error inflation is an I

important issue. Cohen (1982) recommends a hierarchical

procedure in which relations among larger sets of variables

should be significant before testing separate or partialled

subsets. For example, in the current context the overall

association between offender characteristics, personality

factors, and offense clusters should be statistically

significant before testing offender/offense relations with

personality partialled or personality/offense relations with

offender characteristics partialled.

The results are shown in Tables 13, 14 and 15. These

tables are identical with respect to the progressive

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partialling of predictor sets. That is, moving down the

first column of each table indicates that the sets of

predictors were considered si~.ultaneously before proceeding

to investigate subsets of predictors from which others had

been partialled. The tables differ only in their criterion

variables. In Table 13 both contrasts among the offense

groups ( i t intrafamilial vs. chronic groups, and

extrafamilial versus the average of the intrafamilial and

chronic groups) were analyzed as a criterion set, whereas in

Tables 14 and 15 each contrast is analyzed with the other

partialled out. Table 16 summarizes the entire analysis.

Some possible sets are missing from the tables. For

example, the set representing the interaction between

offender clusters proved unreliable in all analyses and

therefore is omitted from the tables. Interactions among ,

offender groups and personality factors could have been

investigated but would have required constructing an

additional 40 variables; a situation that would have been

largely uninterpretable, and essentially meaningless given

the resulting ratio of subjects to variables.

All higher order relations are statistically

significant, meeting the criteria for Type I error

protection and allowing the discussion to focus on the

relationships among partialled single-set predictors to

partialled criteria (i.e. the last four rows of Tables 14-

15, and the last four rows and two columns of Table 16).

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Table 13. Set Correlation ~nalysis of Offender and Personality Variables Related to Coded set of Offense Variables

Independent Variable R~ F df P

o1 - two cluster solution of offender variables O2 - three cluster solution of offender variab1.e~ P1 - MMPI four factors P2 - MCMI four factors Y1 - Intrafamilial group versus chronic group Y2 - Extrafamilial vs. average of Intrafamilial and Chronic

groups R2 - Squared multivarihte (partial, semipartial) correlation

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Table 14. Set correlatirn ~nalysis of Intrafamilial Group Versus chronic Group

Independent Variable R~ F df D

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Table 15. Set Correlation Analysis of the Extrafamilial Group Versus the Average of t h e Intrafamilial and Chronic Groups

Independent Variable R~ F df P

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Table 16. Summary of Set Correlation Analysis

Independent variable Dependent Variable

Y1u2 Yl'~ 2 y2.y1,

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Essentially, those results corroborated the results

discussed in the previous three sections with a few

interesting departures. The two cluster solution for the

offender variables with everything else partialled out

differentiated the extrafamilial offense group from the

average of the intrafamilial and chronic offense groups

(multivariate R2 = .O57, p < .OX) . The extrafamilial

offense group was less likely to have had an abusive history

than either of the other offense groups, who did not differ

from one another (multivariate R2 = .044, ns. )

The relationship between the three cluster solution of

offender variables and the contrast coded offense variables

corroborated the unpartialled results reported above that

found married offenders more likely to commit intrafamilial

offenses (multivariate R2 = .l98, p < .001) . However,

unlike the findings above, there is no significant

difference between the extrafamilial offense group

contrasted with the average of the intrafamilial and chronic

offense groups in terms of which offender group they belong

to.

The relationship between the MMPI factors and the

offense variables was not significant when analyzed without

partialling. However, after partialling the MMPI Samatic

factor differentiated the intrafamilial and chronic offense

groups (multivariate R2 = .O98, p < .05) , although m n e of the MMPI factors significantly discriminated the

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extrafamilial offense group from the average of the

intrafamilial and chronic offense groups (multivariate R~ =

. 0 7 7 , ns).

The relationship between the unique aspects of the MCMI

factors and the contrast coded offense variables indicated

that individuals belonging to the chronic offense clusters

were significantly more likely to obtain a higher score on

the MCMI Bizarre/withdrawn factor and a lower score on MCMI

Somatoform factor than those belonging to the intrafamilial

offense cluster (multivariate R~ = .O85, p < .O5) . Individuals belonging to the extrafamilial offense cluster

were more likely to obtain a higher score on the MCMI

Paranoid factor than were the intrafamilial and chronic

groups (multivariate R~ = .082, p < .05) .

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CHAPTER IV

DISCUSSION

The purpose of the present study was to determine

whether the MCMI could better differentiate sex offenders on

the basis of offender, offense/victim characteristics, than

could the MMPI. The rationale for this was that sex

offenders possibly harbour more subtle personality

differences, best captured by the MCMI, than more

pathological clinical syndromes that the MMPI was designed

to assess. An additional goal of this study was to include

more offender, 'offense, and victim characteristics than

previous MMPI studies, as these variables may confound

results across studies, and make coiparison of results

difficult.

The first part sf the analysis examined the mPI and

MCMI separately in much the same manner as in previous

studies, to facilitate comparison of the present sample with

those used in other studies of sex offenders. The means,

and modes for each scale were calculated, as were the order-

independent two-point codes. The mean and modal MMPI 2-

point code was 2-4/4-2, and was exhibited by 6.3 percent of

the total sample.

This result corroborates previous studies of sex

offenders (Groff & Hubble, 1984; Erickson et al., 1987;

Hall, 1989). Groff & Hubble (1984) did not report the

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percent of their sample that obtained the 2-4/4-2 code,

thereby limiting comparison of their study with the present

research. Erickson et al. (1987) found that only 12.6

percent of their sample of child molesters produced the 2-

4/4-2 profile. Hall (1989) found that only 13.6 percent of

his sample of male sexual offenders against children

produced a 2-4/4-2 2-point code, and concluded the sample

was characterized by multiple MMPI elevations, and that

"sexual offenders are not characterized by a specific MMPI

profile configuration." (page 411).

In the present sample, although the 2-4/4-2 2-point

code was the mean and modal profile, only eight subjects, or

6.3 percent of the total subjects exhibited this profile.

This was a Lower percentage than obtained in Erickson et al.

(1987) and Hall (1989), and could perhaps partially be

explained by the fact that the present study included males

that offended against adults, as well as offenders against

children. However, it would appear that, in agreement with

Hall (1989), no specific MMPI 2-point code profile

configuration characterizes sexual offenders.

Also, a 4-2/2-4 profile sheds little insight into

specific personality characteristics of an individual

obtaining this 2-point code. Lachar (1973) suggested that

this code type is frequently exhibited by a psychopathic

personality who has been ncaughtu, and is consequently

reacting to situational, versus internal, stress.

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Therefore, even if more individuals in this study obtained

such a profile, one could not elaborate on specific

personality characteristics, other than to state that

pending legal consequences appear to be precipitating

psychological discomfort.

The MCMI was analyzed in the same manner as the MMPI,

and this yielded a mean 2-point code of 3-A/A-3 (Dependent-

Anxious) for the total sample. However, the mean scores for

these scales were not clinically elevated. Unlike the MMPI,

the mean and modal 2-point MCMI code were not the same. The

modal order-independent 2-point code for the MCMI was D-A/A-

D (Dysthymic/Anxiety; N=21, 16.5%). Again, a D-A/A-D MCMI '

profile may be situation specific, in that an individual

facing a trial situation is likely to anxious, depressed,

apprehensive, and apathetic. ,

The above analysis essentially fails to illuminate the

personality characteristics of sex offenders, and a salient

MMPI or MCMI profile type for the total sample did not

emerge. Additionally, one may expect individuals to exhibit

the above MMPI/MCMI modal profiles on the basis of their

situation alone. Thus, a more refined statistical technique

was required to explore the underlying personality

differences in the present sample of sex offenders.

The above analysis was carried out on the total sample

of sex offenders, ignoring variation of offender, and

offense/victim characteristics. As previously mentioned,

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this has been an inherent problem with previous MMPI

studies. However, the addition of more offender, offense,

and victim variables created a problem of equal magnitude,

namely the subject/variable ratio increases and the power of

the study decreases. In order to circumvent this problem

the number of personality variables (totalling 33 MMPI and

MCMI scales) was reduced to eight factors, four factors for

each of the MMPI and MCMI instruments. The number of

offender, offense, and victim variables was also reduced

from thirteen to three with the aid of cluster analyses.

Thus, collapsing the total number of variables from 46 to 11

served the useful purpose of allowing the inclusion of many

potentially important variables without compromising the

power of the statistical analyses. This method of analysis

represents a pivotal departure from previous MMPI research >

with sex offenders. Rather than a priori defining groups of

sex offenders as in previous research, the offense and

offender groups were defined empirically. This appears

preferable to assigning subjects to groups that are

determined by an arbitrary set of criteria for group

membership.

Cluster analysis of the offender variables yielded two

meaningful solutions, one producing two clusters, the other

producing three clusters. Cluster analysis of the offense

variables produced one meaningful solution of three

clusters. These clusters will be summarized here to

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facilitate remaining discussion.

Offender Variables

(2 cluster solution)

ona abusive History: - unremarkable history in terms of physical and sexual abuse

- no previous criminal record

Abusive History: - likely to have been physically and/or sexually abused - likely to have a previous criminal record

(3 cluster solution)

Offense Variables (3 cluster solution)

Young : - 30 or younger - employed at unskilled labour - single or in 1st marriage

Unemployed: - between ages 31-40 - unemployed - equally likely to be divorced, single, or married

Married: - oldest of the 3 clusters - employed as skilled laborers, or professionals

- married

Intrafamilial: - one victim - intrafamilial offense - victim 10 years old or younger - 20 or more offense repeats - relatively more serious offense Extrafamilial: - one victim - extrafamilial offense - victim 11 years old or older - one offense - relatively less serious offense Chronic : - two or more victims - both intrafamilial and extrafamilial offenses - victims 10 years old or younger - between 2 and 19 offense repeats - relatively more serious offense

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The present study was essentially atheoretical in that

there was no a priori hypotheses regarding the manner in

which the offenses would be grouped. For example, Grothls

categorization of fixated versus regressed pedophiles was

not necessarily expected to capture the offense groupings.

However, the intrafamilial offense cluster roughly

corresponds to Groth's regressed pedophile category, whereas

the chronic group approximates the fixated category, insofar

as the victims were children. The intrafamilial offenses

were most often committed by married individuals, indicating

that children were not the only preferred object of sexual

orientation. Also, these offenses, by definition, were most

often committed within the family suggesting that these

individuals were not actively searching for victims, rather

they were more situational. The chronic offenses, on the

other hand, were often both intrafamilial and extrafamilial,

indicating that these individuals were actively seeking

sexual contact with children under the age of eleven. The

extrafamilial group does not precisely fall into either of

Grothls categories, primarily because the victims were age

eleven or older, the offense itself was typically of a

relatively minor nature, and a one-time occurrence.

As discussed in the Introduction, previous studies

using the MMPI to discriminate groups of sex offenders

typically a priori categorized groups of sex offenders based

on various offense characteristics (e.g. rapists of adults

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versus rapists of children) and then compared the MMPI

profiles of each group to determine if they differed

significantly. Stated another way, the offense

characteristics were considered the independent variable and

the MMPI profiles were viewed as the dependent variable. In

this study these roles were reversed such that the

personality profiles, along with offender characteristics,

were used to predict the offense types, or in this case,

offense clusters.

The interrelationships among the personality, offender,

and offense variables were investigated using set

correlation analysis. This procedure was used to determine

both the common and unique contributions of personality

variables and offender characteristics to offense variables.

The relationship between the two groups of independent ,

or predictor variables (personality and offender groups)

revealed that individuals with a history of physical and/or

sexual abuse (two cluster solution of offender variables)

were more likely to score higher, on average, on three

personality factors. These were MMPI ~mpulsive/moody and

Sensitivity factors and the MCMI Bizarre/withdrawn factor.

This is not an unexpected finding, given that individuals

with an abusive background would likely harbour more

personality disorders than individuals who did not

experience abuse during childhood. Not surprisingly, the

three cluster solution for the offender variables, which

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consisted of demographic characteristics such as marital

status, employment, and age, were not significantly

correlated with the MMPI and M C M I personality factors.

The criterion variables, or offense clusters were

contrast coded before their relationship with the predictors

was investigated. The intrafamilial and chronic offenses

were relatively more serious than were the extrafamilial

offenses. They typically involved younger victims, more

than one repeat of the offense, and the offense itself

typically included oral sex, digital, vaginal, and/or anal

penetration. However, if one of these offense types could

be classified as the more serious of the two, it would be

the chronic offenses, primarily because they often involved

more than one victim, and these were both intrafamilial and

extrafamilial. The discussion to follow will describe each

of the offense clusters (intrafamilial, chronic, and

impulsive) separately, and the personality and offender

factors that predict them.

The chronic offenses were most often committed by the

Unemployed offender group, and these individuals frequently

had an abusive background. When compared with the

intrafamilial offense group, the chronic offense group

exhibited significantly higher scores, on average, on the

MCMI ~izarre/withdrawn factor and MMPI somatic factor.

Recall that the M C M I scales loading on the

~izarre/withdrawn factor were psychotic ~epression,

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Avoidant, and schizoid. The Avoidant and Schizoid scales

belong to Millon's (1983) basic personality patterns (Axis

11) category. The eight scales from this category reflect

relatively pervasive and enduring traits that are indicative

of premorbid characterological functioning. According to

Millon's (1986) theoretical derivation of pathological

personalities, both scales represent a detached personality

style. This personality style reflects an inability to

experience pleasure from self or others, and a minimal sense

of contentment and joy. Detached types tend to exhibit

increasingly self-alienated and isolated behaviors.

The psychotic Depression scale, which also loads on the

~izarre/withdrawn factor, belongs to the clinical symptom

syndromes category (Axis I), reflecting a more reactive,

transient state. Typically the symptom is precipitated by ,

external events (in this case perhaps a pending trial),

which accentuate the more everyday features of the basic

personality style.

The chronic offense group also scored higher than the

intrafamilial offense group on the MMPI Somatic factor,

indicating a demanding, complaining personality style,

manipulativeness, lack of insight, hostility, repression,

denial, and attention-seeking behaviour. Relationships with

others tend to be superficial. ~epression and anxiety are

often conspicuously absent. Individuals belonging to the

chronic offense group likely do not feel guilt or remorse

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about their offense, and deny responsibility for their

actions. Additionally, it is probable that these

individuals would have a poor prognosis for treatment, but

further research would be required to substantiate this '

speculation.

Intrafamilial offenses were most often committed by the

married offender group. These individuals were also likely

to have had an abusive background. When compared to the

chronic offense group, Intrafamilial offenses were more

likely, on average, to be committed by individuals with

higher scores on the M C M I Somatoform factor.

The M C M I scales that loaded on the Somatoform factor

were Somatoform, Anxiety, Dysthymic, and Borderline. The

first three scales belong to the clinical symptom syndromes

category, while the Borderline scale belongs to pathological

personality disorders category. The latter reflects a

chronic pathology in the overall structure of personality,

and typically individuals exhibiting elevations on one or

more of these scales evidence modest levels of social

competence, due to a failure to learn from previous

difficulties and the tendency to incite self-defeating

circles. High scores on the M C M I Somatoform factor indicate

somatic tension, anxiety, dysphoria, massive interpersonal

ambivalence, feelings of guilt, and a lack of antisocial

behaviour. It appears that these offenders are anxious and

likely to harbour feelings of guilt and confusion about

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their offenses.

Before discussing the third offense group

(extrafamilial offenses), it would be useful at this point

to elaborate on the distinction between the MMPI Somatic

factor and the MCMI Somatoform factor. This is especially

important given that these two factors are not significantly

correlated (refer to Table 12), and each predict a different

offense type. The primary distinction between the two

factors appears to be guilt and anxiety components. Those

individuals with high scores on the MCMI Somatoform factor

likely possess a capacity to experience feelings of guilt

and remorse, and a corresponding lack of antisocial

behaviour. These individuals also appear to be highly

anxious. Individuals scoring high on the MMPI Somatic

factor, on the other hand, are characterized by a lack of ,

guilt feelings, and may harbour antisocial personality

features. Additionally, in contrast to individuals scoring

high on the MCMI Somatoform factor, those scoring high on

the MMPI Somatic factor do not present as anxious. The

common theme between the two factors is that physical

complaints tend to be psychological in origin.

The extrafamilial offenses were most likely to be

committed by the young offender group. These individuals

seldomly had an abusive background. Recall that the

impulsive offenses were considered the least serious of the

three offense groups, and were compared with the average of

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the intrafamilial and chronic offenses.

The Extrafamilial offenses were consistently

discriminated from the Chronic and Intrafamilial offenses by

the MCMI Paranoid factor. The Paranoid and psychotic

elusions scales loaded on the MCMI Paranoid factor,

indicating paranoid behaviour and thinking with the

associated features of suspiciousness, mistrust,

defensiveness, persistent ideas of self-importance and self-

reference, and hostile acting out. The Paranoid and

Psychotic Delusions scales fall into the clinical symptom

syndromes and pathological personality disorders categories

respectively.

The following is a summary of the personality factors

and offender characteristics that predict each of the

offense groups: ,

MCMI Bizarre/withdrawn, MMPI somatic factors; Unemployed

offender group - Chronic offenses MCMI Somatoform factor; ~arried offender group - Intrafamilial offenses

MCMI Paranoid factor; Unskilled Labour group - Extrafamilial offenses

In general, it appears that individuals who are between the

ages of 31-40, unemployed, have been physically and/or

sexually abused, exhibit a detached personality style, and

do not appear to be anxious, depressed, or remorseful, tend

to commit relatively serious, chronic offenses. These

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offenses are likely to be both intrafamilial and

extrafamilial, against children under the age of eleven, and

tend to include oral sex, digital, vaginal, and/or anal

penetration.

Individuals who are employed as professionals or

skilled labourers, married, have been physically and/or

sexually abused, exhibit anxiety, dysphoria, feelings of

guilt, and a lack of antisocial behavior, tend to commit

relatively serious, intrafamilial offenses. These offenses

are typically committed numerous times against one victim

under the age of eleven, and also included oral sex,

digital, vaginal, and/or anal penetration.

Finally, individuals who are employed at unskilled

labour, are under the age of 30, single, have not been

physically or sexually abused, and are suspicious,

defensive, and mistrustful typically commit Extrafamilial

offenses. These offenses are less serious in nature than

the previous two in that they are Ithands offN (e.g. obscene

phone calls, exhibitionism), or fondling only, and the

victims are age eleven or older. ~dditionally, there is

typically one victim only, the offense is extrafamilial, and

a one-time occurrence.

The original question that this study set out to

explore was whether the MCMI would better discriminate sex

offenders on the basis of offender, offense, and victim

characteristics, than would the MMPI. It appears from the

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results discussed above that the MCMI consistently

discriminated the Chronic from the Intrafamilial offenses,

as well as the Extrafamilial offenses from the average of

the Chronic and Intrafamilial offenses. The MMPI only

discriminated the chronic and intrafamilial offenses, and

did not discriminate between the less serious extrafamilial

offense group and the more serious chronic and intrafamilial

groups.

Therefore, it appears that the MMPI is useful in

discriminating sex offense types to the extent that the

offenses are relatively serious, and enduring in nature.

The MCMI, on the other hand, indicated greater predictive

validity in the present study, in that it discriminated the

more serious and less serious offense types. Thus, based on

the results of the present study, both personality >

instruments are useful in the assessment of sex offenders,

but if given a choice between the two, the MCMI has

demonstrated superior predictive validity.

Limitations of Current Study and Sussestions for Future

Research

The current findings are compromised by the following

limitations:

1. The current study did not include a control group for

comparison of MMPI and MCMI protocols. It would be useful

to determine whether MMPI and MCMI protocols differed

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between sex offenders and ronsex offenders, and between sex

offenders and normal, nonclinical populations.

2. It would be interesting to determine whether the factor

structures of the MMPI and MCMI would be replicated in

another sample of individuals charged with sexual offenses.

3. There were several variables that were restricted in

range due to sample size, and were deleted from analyses.

For example, most of the offenders were heterosexual,

offended against females, were Caucasian, and raised by

their biological father and mother. A larger sample size

might have resulted in greater variability or at 1east.more

power to handle such restricted variance, and may provide

interesting results.

4 . The results to the present study provide some insight

into the underlying personality characteristics of a ,

socially deviant population. Unfortunately, the results

have limited utility for aiding the practising clinician in

individual assessments. However, if the results of the

present study were replicated, a new scale could be derived

that would be useful in discr'iminating various types of sex

offenders.

5 . Implications for treatment and recidivism based on

personality characteristics were not explored and clearly

would be a relevant topic for future research. The results

of the present study could not be used prospectively to

predict individuals who would be likely to commit a sexual

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offense because subjects were selected for research after

committing an offense and were not compared to a random

sample of normal controls. However, the current results nay

be have implications for the issues of treatment and

recidivism. The intrafamilial and extrafamilial offender

groups showed personality characteristics that indicate

amenability to treatment. The intrafamilial group typically

harboured guilt feelings that could be used in a therapeutic

manner and prevent further offending. ~ikewise, the

extrafamilial group typically had offended only once and

treatment would likely be successful in preventing

recidivism. The chronic offender group, on the other hand,

exhibited antisocial tendencies, and may be more resistant

to therapy. Therefore, this group may be the most likely of

the three to reoffend. ,

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CHAPTER V

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