Journal article: E. Schreiber, & K. Schreiber (1995).Using relaxation techniques and positive self-esteem to improve academic

achievement of college students. Psychological Reports, 76 (3), 929-930

Westerberg, VM

Date: 19 March 2009

Muscle Relaxation Academic Performance

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INTRODUCTION TO PSYCHOLOGICAL RESEARCH - 1

Question 1

1a.- Draw a construct flowchart that communicates the author´s theory about the muscle relaxation and academic performance. To the two constructs in the flowchart add a credible moderating variable of your choice.

1b.- On the basis of your moderated flowchart draw a credible graph of the construct relationships.

Minimal Moderate Maximal

WarmCold

Muscle relaxation

Acad

emic

Per

form

ance

Room Temperature

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1c.- Describe what your graph depicts (short paragraph)

The above graph shows the increase in academic performance following a course on

muscle relaxation techniques. However, the students whose room was cold during the

relaxation procedure showed a lower academic performance than those whose room was

warm during the procedure, indicating that, in the present study, room temperature had

a moderating effect in the muscle relaxation – academic performance relationship.

Question 2

The authors were looking at the effects of muscle relaxation on various dependent variables. In this context, critically evaluate the internal validity of the study.

The internal validity evaluates how well the operational definition measures the effect

and if something is being missed or measured inadvertently.

The criteria indicated in the table below will be used to discuss the construct validity of

the study regarding academic performance, self-esteem and anxiety. All points will be

considered in the critical evaluation but only the relevant ones will be mentioned

specifically.

Standardised scale (preferable) Strengths Adequate variable level number ( ≥2, otherwise it cannot vary)

Correct magnitude levels (10, 20, 30, 32, 33, 38, 40, 50)Internal validity

evaluation

Sensible variable relationship (linear, curvilinear)

Poor construct validity (inadequate cause-effect relationship)Poor extraneous variable control (noise)

Weaknesses Sample bias Drop outs (not notified, not managed)Measures invalid / unreliable (sometimes, twice a week, often)Statistical analysis inadequate (lacking data, wrong calculations)

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With regard to academic performance, both the control and the relaxation group were

evaluated comparing their mid- and final term grades. The scores obtained by the

relaxation group were significantly superior to those of the control group in both terms.

Academic scores for educational institutions are standardised and approved by the

national and local government educational administrations, that means that they should

be generally considered a valid means to measure academic performance as they would

meet all the strengths and lack (or control) all the weaknesses mentioned in the table

above. Still, in the present study, no note has been made about differences in

performance according to age or gender. Additionally, the control group is larger than the

relaxation group, and the male:female ratio is not well balanced in either group, much

more so in the relaxation group. If these conditions were intentionally obviated in the

article because the data obtained were irrelevant for the study of academic performance,

then, it could be concluded that the internal validity of this construct is good. On the

other hand, if there was in fact a difference and it was not mentioned, either intentionally

or mistakenly, then validity could not be confidentially rated.

As for anxiety, a valid, standardised and accepted scale was used to measure it, namely,

the Cattell & Scheier Anxiety Scale and the result found was that no significant difference

was noted between the groups. However, in this case, a note is made about the

differences in anxiety level scores between men and women as, in fact, there is a striking

difference in variability between genders. Looking at the differences in SD of both groups,

anxiety levels are much more spread out among women. This, together with the wider

range in scores, indicates that anxiety levels are very heterogeneous amongst women and

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that the resulting mean anxiety level score from the addition of male and female scores

may be misleading. Separate evaluation of men and women should be considered to

control gender as a modifying variable.

Construct validity evaluation in terms of self-esteem differs significantly from that of the

previous two variables. In the first place, the scale used in this study to measure self-

esteem is Cattell & Scheier´s Anxiety Scale, which is designed to measure anxiety, not self-

esteem. Additionally, self-esteem was measured on the basis of response to 2 questions

each with only 2 levels of variability and whose validity cannot been proven. If

researchers had used a standardised (reliable) test, like Rosenberg´s Self-Esteem Scale,

they would have obtained valid results for this variable. Instead, due to a deficient

procedure used, the internal validity of the evaluation of self-esteem should be rated as

poor and be regarded as unreliable.

Summarizing, the internal validity of 2 out of the 3 constructs is good, and given that

internal validity is a pre-requisite to evaluate external validity, it has to be assumed that

the overall internal validity is fair and therefore external validity can be assessed.

Question 3

Describe, and comment on, the external validity of the study, systematically covering all

relevant issues.

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External validity refers to how well the research results can be generalised across

participants (target and general population), across different operational definitions and

across settings (experimental and mundane realism and ecological validity).

Participants were 52 college students aged 19 to 40. The sample is small and very possibly

not representative of the overall college (target) population with regard to male : female

ratio. The results could possibly be generalised to other country´s college students but it

could hardly do so to the general population, where the age range is wider (students-

other adults). It could be assumed that gender ratio in colleges reflects that of the general

population, but there are significant differences in gender distribution depending on the

studies, and one should expect the proportion of women studying midwifery to be higher

than that of men. Conversely, technical and engineering studies are more commonly

chosen by men.

With regard to the evaluation of external validity across different operational definitions,

no graphs have been provided showing how levels were labelled and how many levels per

variable were considered. The C- score average prior to relaxation increased, but did it

reach B, B+, A or A+? No reference is made to the magnitudes or levels used to measure

anxiety. Self-esteem was rated as negative or positive, which is rather vague, and no

middle values were given. Lower than usual, as usual, and higher than usual would have

been a better choice.

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To assess generalisation across settings, it should be noted that the experiment is not

dated, and therefore it is hard to extrapolate settings in terms of time. If the test was

done in the 70s maybe the percentage of males enrolled in tertiary education was higher

than that of women and that would explain, in part, gender distribution in the samples.

As for experimental realism (engagement of participants in the study), although there is

no direct mention to it, drop outs did not occur as, according to the data in the tables

given, all the students in both groups were considered in the various measurements of

the different variables. This could by itself be an indicator of an elevated involvement of

participants in the experiment, the outcome of which would be the possibility to get

higher grades which is a good incentive to any responsible student.

The reasons why this experiment may have a good ecological validity, at least in terms of

increasing performance / skills, will now be discussed. Although the relaxation sessions

very possibly took place in a classroom and in any case in a controlled environment,

without distractions of note, it should be possible to reproduce them in the real world, in

an uncontrolled environment. Therefore, if a student (or any adult of the general

population) wishes to carry on / start up the relaxation techniques in the future, s/he

could represent the experimental conditions in an adequate real-life environment and

carry on. This concept could be the object of a follow-up experiment if the training

sessions were recorded and sold as DVDs and the general population who used it tested

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on how much their professional or academic performance improved after a 10-week

period with twice a week sessions.

Real life conditions (a classroom, an office, a room at home) are adequately mimicked

(mundane realism) in this study and individuals in the target and general populations

should expect results to be equivalent in terms of skill improvement.

This experiment carried out with the above mentioned modifications, namely the control

of gender as a modifying variable in anxiety evaluation, the use of an adequate scale to

measure self-esteem, samples being more homogeneous in numbers and gender, the

indication of the test date, and better labelling of scales among the most relevant ones,

would make that this study turned into one with a much better overall validity, reliability

and with a high potential of generalisation.