Download pdf - A preliminary investigation of the reliability and validity of the Brief Assessment Schedule Depression Cards and the Beck Depression Inventory-Fast Screen to screen for depression

INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY

Int J Geriatr Psychiatry 2008; 23: 531–536.

Published online 16 November 2007 in Wiley InterScience

(www.interscience.wiley.com) DOI: 10.1002/gps.1933

A preliminary investigation of the reliability and validity ofthe Brief Assessment Schedule Depression Cards and theBeck Depression Inventory-Fast Screen to screen fordepression in older stroke survivors

A. K. Healey1,2, I. I. Kneebone1,2*, M. Carroll1 and S. J. Anderson3

1Department of Psychology, University of Surrey, Guildford, UK2Surrey Primary Care NHS Trust, UK3South Downs Health NHS Trust, UK

SUMMARY

Objective To conduct an initial assessment of the reliability and validity of the Brief Assessment Schedule DepressionCards (BASDEC) and the Beck Depression Inventory-Fast Screen (BDI-FS) to screen for depression in older strokesurvivors.Methods Participants from four inpatient rehabilitation units completed the BASDEC and the BDI-FS together with theHospital Anxiety and Depression Scale (HADS) for comparison. The Structured Clinical Interview for DSM-IV Axis 1Disorders (SCID) was then completed with all participants to ascertain a criterion depression diagnosis. The BASDEC andBDI-FS were subsequently completed for a second time.Results Forty-nine stroke survivors (M¼ 78.80, SD¼ 6.79 years) were included. The BASDEC and BDI-FS demonstratedacceptable internal consistency and test–retest reliability. The BASDEC (cut-off �7) resulted in a sensitivity of 1.0 andspecificity of 0.95 for detecting major depression whereas the BDI-FS (cut-off �4) had a sensitivity of 0.71 and specificity of0.74. When participants with minor depression were included in analyses, sensitivity lowered to 0.69 (specificity¼ 0.97) forthe BASDEC and 0.62 (specificity¼ 0.78) for the BDI-FS.Conclusions The BASDEC and BDI-FS were found to have acceptable reliability. The BASDEC demonstrated someadvantage in criterion validity over the BDI-FS at the examined cut-offs. Copyright # 2007 John Wiley & Sons, Ltd.

key words— depression; rehabilitation; reliability and validity; screening; stroke; sensitivity and specificity

INTRODUCTION

Depression affects approximately one-third of strokesurvivors (Hackett et al., 2005) and is associated withpoor outcome, including mortality and physicaldisability (Dennis et al., 2000; House et al., 2001).There are strong concerns that it goes untreatedbecause it is often undiagnosed (Hackett et al., 2004).On this basis, routine screening has been recom-mended (Royal College of Physicians, 2004).

*Correspondence to: Dr I. I. Kneebone, Haslemere Hospital, ChurchLane, Haslemere, Surrey, GU27 2BJ, UK.E-mail: [email protected]

Copyright # 2007 John Wiley & Sons, Ltd.

A recent review of potential measures for routinescreening for mood disorders after stroke (Bennett andLincoln, 2006) identified the Brief AssessmentSchedule Depression Cards (BASDEC: Adsheadet al., 1992) and the Beck Depression Inventory-FastScreen for medical patients (BDI-FS: Beck et al.,2000) as meriting investigation. These instrumentshave potential for screening for depression as they arebrief, require minimal training to administer, have fewor no somatic items (which can complicate identifi-cation of depression in this client group), and havedemonstrated high sensitivity and specificity fordetecting depression in older people with physicalhealth problems (Loke et al., 1996; Scheinthal et al.,

Received 27 April 2007Accepted 7 September 2007

532 a. k. healey ET AL.

2001). The BASDEC and BDI-FS also have itemsreferring to suicidal ideation, important as strokesurvivors are at an approximately doubled risk ofsuicide (Teasdale and Endberg, 2001). The BASDEChas the added advantage of a particularly service-userfriendly design, due to its novel ‘card’ format, withsimple response categories.

The aims of this study were to investigate the use ofthe BASDEC and BDI-FS as depression screeningmeasures with older stroke survivors in an inpatientrehabilitation setting by: (1) conducting an assessmentof the scales’ test–retest and internal reliability, (2)assessing the criterion validity by comparing theresults of the scales to depression diagnosis accordingto Diagnostic and Statistical Manual IV (DSM-IV:American Psychiatric Association, 1994) criteria asassessed by the Structured Clinical Interview forDSM-IV (SCID: First et al., 1997) and (3) comparingthe performance of these scales to the HospitalAnxiety and Depression Scale (HADS: Zigmond andSnaith, 1983) which is one of the best validatedself-report scales for depression screening in strokesurvivors (Bennett and Lincoln, 2006).

METHOD

Participants

Participants, who were medically stable, were rec-ruited from four inpatient rehabilitation services forstroke survivors. Recruitment took place over a total of14 months. Exclusion criteria included being under65 years of age, under 2 weeks or more than 6 monthspost-stroke, dysphasia to the extent that completion ofthe depression rating scales or the interview would bedifficult and cognitive impairment indicated by a scoreof less than 8 on the Abbreviated Mental Test(Hodkinson, 1972) or less than 24 on the Mini-MentalState Examination (Folstein et al., 2000). Participantsgave informed consent.

Measures

The BASDEC (Adshead et al., 1992) was developedfor use with older people in a hospital wardenvironment. It is a set of 19 statements relating todepression symptoms, each written on a separate card(8.2 cm x 10.4 cm). The respondent is asked to placethe statement card next to either a ‘True’ or ‘False’card according to their current view. ‘True’ statementsare scored 1 point, with the exception of twostatements which are weighted as 2 points. ‘False’statements are scored 0. ‘Don’t Know’ responses are


scored 0.5 points. The maximum possible score is 21,higher scores indicating greater depressive sympto-mology. Studies with groups of medically-ill olderpeople have found high sensitivity (>0.80) andspecificity values (>0.90) with reference to depressiondiagnosis ascertained by structured clinical interviews(e.g. Loke et al., 1996; Yohannes et al., 2000) usingthe test developers recommended cut-off (�7).

The BDI-FS (Beck et al., 2000) is comprised ofseven items from the 21-item Beck DepressionInventory-II (Beck et al., 1996). No somatic itemsare included to increase specificity for medicalpatients. Items are rated for the past 2 weeks on afour-point likert scale (0–3), giving a maximum totalscore of 21. An optimum cut-off score of �4 had highsensitivity (1.0) and specificity (0.84) compared todepression diagnosis from a structured diagnosticinterview in a group of older medically ill outpatients(Scheinthal et al., 2001). This optimum cut-off isconsistent with previous studies reported in the testmanual (Beck et al., 2000).

The HADS (Zigmond and Snaith, 1983) is a14-item self-report rating scale divided into anxiety(HADS-A) and depression (HADS-D) sub-scales. Itwas designed for use with hospitalised, medically illpatients. Each item is rated for the past week on afour-point likert scale (0–3). The maximum score,indicating highest symptomology, on each sub-scale is21. Reliability and validity data are available for itsuse as a screening measure in stroke (Bennett andLincoln, 2006). The cut-off recommended by the testdevelopers for possible clinical depression is �8 onthe HADS-D and this has been validated for strokesurvivors (Aben et al., 2002).

The SCID (First et al., 1997) is a semi-structuredinterview schedule for making the major DSM-IVAxis I diagnoses. The sections related to mooddisorder were administered to ascertain whetherparticipants met criteria for a DSM-IV diagnosis ofmajor depression or minor depression (DSM-IVresearch criteria).

Procedure

Participants first completed the BASDEC, BDI-FSand HADS. Order of completion was counterbalancedto nullify order effects (Lucas, 1992). The standar-dised instructions, questions and responses were readaloud to each participant by an assistant (graduate)psychologist. Participants also had a copy of thedepression measures in front of them. If possible,participants completed the forms or placed theBASDEC cards themselves, if not this was completed


DOI: 10.1002/gps

Table 1. Distribution of scores on the depression rating scales forthe non-depressed and depressed participants

Depression RatingScale (cut-off)

Non-DepressedParticipants

(n¼ 36)

Depressed Partici-pants (n¼ 13)

Mdn IQR Mdn IQR

BASDEC (�7) 2 2–3.88 9 3.5–9.5BDI-FS (�4) 1 0–3 6 2–9HADS-D (�8) 4 1–8 9 5.5–11.5

BASDEC¼Brief Assessment Schedule Depression Cards;BDI-FS¼Beck Depression Inventory—Fast Screen; DepressedParticipants¼ participants with a diagnosis of major or minordepression; HADS-D¼Hospital Anxiety and Depression Scale—Depression Scale; IQR¼ Interquartile Range; Mdn¼Median.

screening for depression in older stroke survivors 533

by the assistant psychologist. A doctoral trainee inclinical psychology, blind to the results of thedepression rating scales and clinical informationabout the participant and who had completed therecommended training for administration of the SCID(First et al., 1997), conducted this interview within 7days of test administration. Following the SCID and7–10 days following the initial completion of thedepression rating scales, the participants werere-administered the BASDEC and BDI-FS. Demo-graphic and clinical information was collected foreach participant.

Data analysis

Internal reliability was measured by Cronbach’s Alphafor the BDI-FS and HADS-D and by Kuder-Richardson’s 20 Formula for the BASDEC as it isbased on dichotomous data. Test–retest reliability andcorrelations between the measures were assessedusing Kendall’s tau-b correlation coefficient. Firstly,as scores on the measures are ordinal data, secondly,due to the number of tied ranks in the data and thirdly,it is considered a better estimate of the correlation inthe population than Spearman’s correlation coefficientand is therefore more appropriate when an estimationof the size of a relationship is of interest (Arndt et al.,1999).

A test-criterion design was used to investigate theconvergent evidence for the validity of the BASDECand BDI-FS. This was analysed by calculatingsensitivity, specificity, positive and negative predictivevalues and likelihood ratios [including their 95%Confidence Intervals (CI)] for above cut-off scores andDSM-IV diagnosis of depression assessed by theSCID considered as dichotomous variables. Agree-ment between the BASDEC and BDI-FS and the SCIDdiagnosis was also determined using the Kappastatistic which corrects for chance agreement. Valueswere calculated for the HADS-D for comparison.

RESULTS

Study participants

The participants were 21 males and 28 females whohad a mean age of 78.80 (SD¼ 6.79). All participantswere White British or Irish, the majority were married(44.9%) or widowed (30.6%) and had lived in theirown home prior to admission (85.7%). Participantswere first assessed at a median of 41 days (range¼16–113) post-stroke, stroke-type was classified as lefthemisphere (63%), right hemisphere (28.6%) or other


(8.1%). Participants impairment in activities of dailyliving ranged from minimal to severe (data notrecorded in medical notes for seven participants)as measured by the Barthel Activities of DailyLiving Index (Mahoney and Barthel, 1965) (n¼ 27,Mdn¼ 9, range¼ 0–19) or the Functional Indepen-dence Measure (Hamilton and Granger, 1994) (n¼ 15,Mdn¼ 43, range¼ 19–69).

Seven participants (14.3%) met DSM-IV criteria formajor depression as measured by the SCID and six(12.2%) met criteria for minor depression. A summaryof the distribution of total scores on the depressionmeasures according to diagnosis is given in Table 1.

Reliability

The internal consistency of the BASDEC (KR-20¼0.77), BDI-FS (a¼ 0.75) and HADS-D (a¼ 0.80) wasacceptable (Field, 2005). The BASDEC (t(43)¼ 0.66,p< 0.001) and BDI-FS (t(43)¼ 0.63, p< 0.001) alsohad acceptable test–retest reliability. Six participantswere discharged before the second administration ofthe depression rating scales could take place.

Validity

Total scores on the BASDEC, BDI-FS and HADS-Dwere significantly correlated beyond the 0.001 level.The correlations of the BASDEC with the BDI-FS andHADS-D, and the BDI-FS with the HADS-D, were,respectively, 0.57, 0.40 and 0.44, providing conver-gent evidence of validity.

The sensitivity, specificity, predictive values andlikelihood ratios for each measure compared to theSCID diagnosis are presented in Table 2. The median


DOI: 10.1002/gps

Tab

le2

.E

ffec

tiven

ess

of

the

BA

SD

EC

,th

eB

DI-

FS

and

the

HA

DS

-Dco

mp

ared

wit

hD

SM

-IV

dia

gn

osi

s

Mea

sure

(cut-

off

)S

ensi

tiv

ity

(95

%C

I)S

pec

ifici

ty(9

5%

CI)

Po

siti

ve

pre

dic

tive

Val

ue

(95

%C

I)N

egat

ive

pre

dic

tive

Val

ue

(95

%C

I)P

osi

tive

lik

elih

oo

dra

tio

(95

%C

I)N

egat

ive

lik

elih

oo

dra

tio

(95

%C

I)

MD

MD

and

MIN

DM

DM

Dan

dM

IND

MD

MD

and

MIN

DM

DM

Dan

dM

IND

MD

MD

and

MIN

DM

DM

Dan

dM

IND

BA

SD

EC

(�7

)1

.00

(0.6

5–1

.0)

0.6

9(0

.42

–0

.87)

0.9

5(0

.84

–0

.99

)0

.97

(0.8

6–1

.0)

0.7

8(0

.45

–0

.94)

0.9

0(0

.60

–0

.98)

1.0

0(0

.91

–1

.0)

0.9

0(0

.76

–0

.96)

21

(6.3

3–7

6)

24

.92

(4.6

4–1

43

.88

)0

.00

(0.0

0–0

.37

)0

.32

(0.1

3–0

.60)

BD

I-F

S(�

4)

0.7

1(0

.36

–0

.92)

0.6

2(0

.36

–0

.82)

0.7

4(0

.59

–0

.85

)0

.78

(0.6

2–0

.88)

0.3

1(0

.14

–0

.56)

0.5

0(0

.28

–0

.72)

0.9

4(0

.80

–0

.98

)0

.85

(0.6

9–0

.93)

2.7

3(1

.20

–5

.16)

2.7

7(1

.29

–5

.76)

0.3

9(0

.11

–0

.90

)0

.49

(0.2

2–0

.87)

HA

DS

-D(�

8)

0.8

6(0

.49

–0

.97)

0.6

2(0

.36

–0

.82)

0.6

9(0

.54

–0

.81

)0

.69

(0.5

3–0

.82)

0.3

2(0

.15

–0

.54)

0.4

2(0

.23

–0

.64)

0.9

7(0

.83

–0

.99

)0

.83

(0.6

6–0

.93)

2.7

7(1

.40

–4

.70)

2.0

1(1

.00

–3

.80)

0.2

1(0

.04

–0

.77

)0

.55

(0.2

5–1

.00)

BA

SD

EC¼

Bri

efA

sses

smen

tS

ched

ule

Dep

ress

ion

Car

ds;

BD

I-F

S¼

Bec

kD

epre

ssio

nIn

ven

tory

––

Fas

tS

cree

n;

DS

M-I

V¼

Dia

gno

stic

and

Sta

tist

ical

Man

ual

of

Men

tal

Dis

ord

ers,

4th

edn

(Am

eric

anP

sych

olo

gic

alA

sso

ciat

ion

,1

99

4);

HA

DS

-D¼

Ho

spit

alA

nx

iety

and

Dep

ress

ion

Sca

le–

–D

epre

ssio

n;

MD¼

Maj

or

Dep

ress

ion

;M

IND¼

Min

or

Dep

ress

ion.



time between the first administration of the depressionrating scales and the interview was 3 days.

Sensitivity, specificity, predictive values andpositive likelihood ratios were highest for theBASDEC, where a cut-off of �7 correctly identifiedall cases of major depression and produced only twofalse positives (4.1%). This resulted in an ‘almostperfect’ level of agreement (k¼ 0.85, 95%CI¼ 0.65–1.0) (Landis and Koch, 1977). The BDI-FS(cut-off �4) missed two participants with majordepression (4.1%) and produced 11 false positives(22%). This is reflected in lower sensitivity andspecificity, predictive values and a ‘fair’ overall levelof agreement (k¼ 0.29, 95% CI¼ 0–0.62). Forcomparison, the HADS-D (cut-off �8) missed onecase of major depression (2%) and produced 13 falsepositives (26.5%), resulting in an acceptable level ofspecificity with lower specificity and predictivevalues. The overall level of agreement was fair(k¼ 0.32, 95% CI¼ 0.02–0.62). When major andminor depression were considered together, theaccuracy of all measures was reduced at the examinedcut-offs. The number of false negatives increased to 4(8%) for the BASDEC and 5 (10%) for the BDI-FSand HADS-D.

DISCUSSION

The BASDEC and BDI-FS were found to haveacceptable internal consistency and test–retestreliability in this cohort of older stroke survivors inan inpatient rehabilitation setting. The BASDECdemonstrated excellent criterion validity with refer-ence to the SCID when considering a major depressiondiagnosis. The BDI-FS and the HADS-D were lessaccurate in relation to the criterion at the examinedcut-offs. Bennett and Lincoln (2006) suggest that as aguideline sensitivity values should be over 0.80 andspecificity values should be over 0.60 for depressionscreening measures following stroke. These guide-lines were satisfied for the BASDEC and HADS-Dwhen major depression was considered, but not for theBDI-FS which had a sensitivity value below 0.80.However, when major and minor depression wereconsidered together, the sensitivity for all measuresfell below this guideline value, though the specificityvalues remained acceptable.

A strength of the study was the use of a structuredclinical diagnostic interview as a criterion measure ofdepression which was administered regardless ofparticipants’ rating scale scores and blind to the resultsof these measures. However, there are several aspectsof the study which limit the interpretation and


DOI: 10.1002/gps

screening for depression in older stroke survivors 535

generalisability of the findings. The BASDEC andBDI-FS were investigated at previously evidencedcut-offs, reflecting how clinicians may use thesemeasures. Further research with a larger sample wouldbe necessary to use a receiver operating curve analysisto identify optimum cut-offs for the measures. Thiswould indicate, for example, whether a lower cut-offwould increase sensitivity for detection of minor aswell as major depression whilst maintaining adequatespecificity. The findings are also limited by the samplesize which contributed to the relatively low precisionof the sensitivity, specificity, predictive and likelihoodvalues, indicated by wide 95% CI. The prevalence ofdepression was also lower than the expected third(Hackett et al., 2005). Several factors may havecontributed to this, for example, stroke survivors withdepression may have been less likely to volunteer forthe study. Furthermore, stroke survivors who werebeing treated for depression were included, thosesuccessfully treated may not be identified as depressedby a clinical assessment. Responsiveness to change inmood was not investigated and this would be avaluable area for further research as it is important tohave measures that can also be used to assess theeffectiveness of intervention. Further research of theBASDEC would usefully include stroke survivorswith expressive dysphasia as the format of theBASDEC suggests it could potentially be used withthis client group.

The findings of this study provide clinicians andresearchers who may consider using the BASDEC orBDI-FS with preliminary information regarding theirpsychometric properties for this client group. TheBASDEC may prove to be particularly useful where asimple response format is required.

KEY POINTS

� Depression affects approximately one-thirdstroke survivors and is associated with pooutcome.

� The format and content of the BASDEC anBDI-FS make them suitable screening tools fthe assessment of depression following stroke

� This study investigated the psychometric propeties of the BASDEC and BDI-FS with oldstroke survivors and found them to havacceptable internal consistency and test-retereliability. The BASDEC demonstrated somadvantage in criterion validity over the BDI-Fat the examined cut-offs.


ofor

dor.r-eresteS

ETHICAL APPROVAL

The study was approved by South West Surrey LocalResearch Ethics Committee, Brighton and Mid SussexLocal Research Ethics Committee, North West SurreyLocal Research Ethics Committee and University ofSurrey Ethics Committee.

CONFLICT OF INTEREST

None.

ACKNOWLEDGEMENTS

Financial support was provided by Surrey PrimaryCare NHS Trust through the UK National HealthService, Research and Development Fund, Budget 1.

Firstly, we are very grateful to the stroke survivorswho gave their time and energy to participate in theproject. We would like to thank John Barker,Samantha Hull, Mary Kelly, Rhona McGurk, TinaSargeant, Dia Soilemezi, Kim Stephenson and JanWheatcroft for their assistance with data collection.The inclusion of the study site at Frimley Park Hos-pital NHS Trust would not have been possible withoutthe support of Dr Keith Mundy, Consultant Physician.Thank you to the managers, consultant physicians andmulti-disciplinary teams in the stroke rehabilitationservices at Farnham and Milford Community Hospi-tals (Surrey Primary Care NHS Trust), Frimley ParkHospital (Frimley Park NHS Foundation Trust) andSouthlands Hospitals (South Downs Health NHSTrust) for their support of the study.

Early versions of this work were presented at the2006 PSIGE (Psychologists Working with OlderPeople, British Psychological Society Conference,University of Sussex, Brighton, UK), which includedthe publication of a conference abstract.

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