Keywords |
| Stress, Undergraduate pharmacy, Academic performance, Reliability,
Convergent validity, Criterion validity, Construct validity |
Background |
| Stress is an interesting concept to study by health care professionals for hundred years
1. Stress has a lot of definitions and suggested models showing how it affects human.
Many studies identify it as a nonspecific response (different physical and chemical
responses) of the body to any demand upon it. The demand itself is called stressor
(situations which trigger stress). Others introduce stress as the reaction or
mobilization of the body’s resources in response to a stimulus (stressor). Stress
response would interrupt physiological and psychological homeostasis. It requires
acting many efforts to reach equilibrium between the person and the surrounding
environment. Continual stress interferes with the normal functioning of the body by
lowering the immune system and eventually makes the body succumbs to disease 2.
Resolving of stress by personal steps to avoid the stressor is referred to as coping.
Some stress may be beneficial to graduate students by increasing their motivation and
productivity3. When academic stress is perceived negatively or becomes excessive, it
may hurt academic performance and health4. In a Taiwanese study 5 among medical
students, authors had discussed the negative physio-psychological responses and
behavior changes of students under a range of stress levels. Research supports the
existence of higher stress levels in students in higher education than the general public
6 and in health care profession students higher than other programs7. |
| The workplace and environment are a major playing factors in stress 8. Common
stressors that trap college students within the academic environment to stress include
many domains. When the family decides the course for their son, he/she may live in
stress for the whole candidature. Other examples of stress in academic life may extend
to high academic ambition, confusing assignment guidelines, perception about the
curriculum structure and career benefits of it, concerning about faculty/advisor
relations especially when the faculty is unsupportive for students. Financial burden,
peers pressure, romantic problems in the school, general social mistreatment, and
others are some interpersonal stressors. For health care profession students, the picture
is similar academically but with adding some clinical training related stress. Skills and
attitudes required in medical training, burden behind perceived lack of proper clinical
knowledge, inadequate clinical supervision to act as health care professional, and
inability to match between clinical and academic materials may be some rolling
domains and extra stressfulness. |
| Ancient assessment of stress in medical and dental students had proved an existence
of dysfunctional stress during academic life 9-10. Pharmacy educational process is
similar to the medical one which is strenuous as well 11. It has been hypothesized that
stress may be an important determinant of whether a pharmacy graduate students
complete their course of study in a timely manner, or even at all 12. Neither much is
known about the impact of the fashionable embodying of academic-clinical
curriculum of pharmacy program on welfare of students nor type of such stressors. |
| Stress is not an entity which can be measured directly 13. It is usually assessed
psychologically by reporting the perceptions of an individual through a number of
items that can be grouped collectively as stress scale or stress questionnaire. Many stress scales have been developed and used generally to study stress among college
students like the Academic Stress Scale (ASS)14 or the Student Stress Inventory
(SSI)15-16. Identifying stress and categorize it specifically for certain students requires
specially designed tools for each population of students. |
| Majority of the research has been conducted for medical, nursing, or dental
candidature 17-19 among other health care profession students. The Medical Education
Hassles Scale (Hassles-R)20-22, The university of Calgary Stress Questionnaire 23-24,
Stress In Medical School Scale (SIMS)25 are examples of special tools to measure
stress in medical students. For dental students the Dental Environmental Stress
Survey (DESS)26 had been mostly used by many studies27-31. For nursing students,
there is the Clinical Stress Questionnaire (CSQ)32, The Student Nurse Stress Index
(SNSI), Beck and Srivastava Stress Inventory (BSSI), The Nurse Stress Scale (NSS)33
and others. Even for clinical psychology students, the Psychology Student Stress
Questionnaire (PSSQ) 3 can be recognized. |
| For pharmacy students, there is no specific tool designed to assess stress in academic
life. The Modified Stress Questionnaire is a derived scale that measures stress in
administration graduate pharmacy students 12. The original questionnaire was
developed in 1983 to compare stress in medical, law, chemistry, and psychology
students 13. However, other studies that carried on pharmacy graduate students used
general and nonspecific tools. Gupchup 34 had used the Student-Life Stress Inventory
(SLSI) 35 among doctor of pharmacy (Pharm.D.) fellows. In another similar study36,
authors used the Perceives Stress Scale 37 to correlate stress with Health Related
Quality of Life (HRQOL) among Pharm D students. Weekly Stress Inventory (WSI)
38, and Derogatis Stress Profile (DSP) 39 had been used by Dutta 11 in their comparison
between different schools of pharmacy within second year Pharm.D. candidates. In
respect to undergraduate pharmacy students, Henning 40 had used the Brief Symptom
Inventory (BSI) along with the Clance’s Imposter phenomenon Scale (CIPS) to
compare stress between pharmacy, medical and nursing students. Another study 6
which carried on degree students had used the Beck-Scrivastava Stress Inventory
(BSSI), and the General Health Questionnaire (GHQ-30) to investigate the perception
of level and sources of stress between students enrolled in nursing, medicine,
pharmacy, and social work programs. |
| Having a specific valid and reliable scale that occupy potential stressors encountered
by pharmacy undergraduates would be important for researchers and program
coordinators to compare stress level with academic performance and welfare between
different schools of pharmacy. This article outlines the stages of developing Stress in
Academic Life Scale (SALS) to be specifically used. It emphasizes on the assessment
of the needed psychometric properties of the tool and consideration of future work
that may be required. |
Method |
| Newly constructed scales should be developed using well defined and rigorous methodology and psychometric analysis 41. Building of SALS as valid and stable
questionnaire occurred through 3 stages: generating items and aggregating into
common factors; reliability and pilot testing; and items reduction to decide the last
structure for further validity. |
| From a thorough literature search among many questionnaires used to measure stress
in undergraduates, seven scales have been selected to be sources. Some underlying
theoretical structure, as well as enhancement of content validity for SALS would be
enhanced by employing the nearest scales to the objective of the study 42. A group of
five pharmacy students from the proposed target population came from different years
of study had interviewed for 30 minutes. Their opinions comments about the
preliminary developed questionnaire SALS were collected and helped in improving
some items. SALS’s content was 54 items at that stage waiting for face and content
assessment. The 54 items distributed meaningfully to load under 6 theoretical
stressors which were suggested basing on the most applicable components of stress in
pharmacy school. These were pertaining to stress related to: relationship with
lecturers; exams and assignments; perception towards the curriculum; orientation to
the social environment within the school; quality of teaching and classrooms;
personality issues; and other academic stressors. The 54 items were extending to
summarize common situations and events in academic life. Some clinical-training
précised items were distributed in the components according to the closest meaning
loading. All the items did not confound with self-report measures of general
psychology stress. |
| Table presents sources of constructing the preliminary pool of items that constructed
SALS as questionnaire. 28 items were created from other sources, while other 26
items were created from the vision of the first author by the aid of the semi-focus
group. |
| Items were generated in a way that requires the student assess his/her past situations
in the school as stressful, and rate them subjectively according to any previous
reaction towards that particular event. The wording of the items had been refined
many times to condense meaning and simplify the language. A couple of linguistics
contributed their comments to strength the syntax. The direction of the meaning for
some adapted items was modified to match the response for the applied ordinal
Likert’s scale ranging from 0 (Not Stressful or Not exist) to 3 (Severely stressful)
options. Higher total scores indicated greater perceived stress. |
| Items arrangement within the multidimensional scale was reviewed by a panel of
experts. Test for clarity was performed by each of the panel members who were asked
to evaluate the questionnaire and demonstrate the content validity. The panel
contained 7 postgraduate pharmacists and 2 lecturers from School of Pharmacy/USM;
in addition to two lecturers (developmental psychologists) from School of Social
Sciences/USM, and two clinical psychologists from Penang Hospital and Adventist
hospital had demonstrated construct validity. Notes taken from them were used to
amend the questionnaire by subsequent revisions. During the period of content
validity, some items were dropped because of redundancy and some items were
reworded for clarification; resulting in a 48-item questionnaire to be used for pilot testing. Pilot study planned for checking understandability and face validity as well as
investigating some psychometric properties of all of the 48 items through which can,
therefore, contribute to establish construct validity 41. Pilot study: The 48-items SALS
was surveyed by 100 students as a minimum number of cases relevant to allow
conducting psychometric analysis47-48 . The respondents were asked to report a sign
near any item they found it vague. A space was there to give comment about how they
suggest the item to be better. The students who participated in the pilot test were not
included in the main research. Piloting helped testing for clarity and lack of
ambiguousness. Factor analysis then conducted for the 100 cases with focusing on the
Anti-image matrix correlational coefficients. The Kaiser-Meyer-Olkin Measure of
Sampling Adequacy (KMO) value was .768 and the Bartlett's Test of Sphericity was
significant (<.000) which gave a green light to interpret the analysis49-50 . The total
reliability was very high (.932) at that stage. As a result behind deleting items with
low coefficients (<0.5) 51, SALS dropped from 48 items to 40 ones. The details of
pilot study was published elsewhere 52. |
Participants and Framework |
| The study was approved by the faculty of School of Pharmaceutical Sciences in USM.
Ethics committee approval was granted for the main study which dealt with
psychophysiology of stress. Written consent was gained from participants prior to
experimental session during which the survey conducted. The concert form contained
an assured statement that their responses would be confidential and anonymous. |
| A total of 388 pharmacy undergraduate students had participated in the experiment.
Filling the questionnaires was done during by ranking the stressfulness of each item
according to the ordinal given scale. The questionnaire was designed for selfcompletion,
with all necessary instructions provided in written format (in the cover
letter of the questionnaire) to minimize administrator bias. A minimum time given to
perform the task is 3-4 minutes to insure commitment and to diminish non-response
error. These 388 students counted 75% of the total number of students in the school at
the year of research (2009 /second semester). Sampling was by volunteering to
participate. The answers were transferred from the questionnaires sheet to the
computer by the same codes provided for answering (0 to 3) of Likert’s scale and data
analyzed by SPSS version 15 windows software. |
Psychometric Analysis |
| Factor analysis is run to investigate the multidimensional structure of the scale by
discovering items loading under common factors that all together will gauge an
underlying theoretical concept or parameter. This type of analysis helps in data
reduction and gives the closest structure of the tool that matches its measure with the
least stuff and therefore support construct validity 47, 53-54. A principle component
extraction with Varimax Orthogonal rotation was performed for the 40 items SALS to identify the domains and their items loading (n=388). This analysis was run to
explore the interrelationship between the components. |
| Some standard criteria were monitored before running the rotation. These include
deleting any factor with eigen value of less than 141, deleting any item with item-total
correlation coefficient of less than 0.3 55-56 . After insuring that none of them were
applicable, a Varimax Orthogonal rotation was run for the 40 items. The first
rotational matrix showed 10 factors prior to deleting the weakly psychometric ones.
Deleting such items was done one by one in each rotation according to 2 conditions;
any item which have loading value of less than 0.4 value 44, 54, 57 ; and any item with
cross loading in more than one factor of a value of 0.4 50, 58-59. Rotation was performed
till all the remaining items have no more cross loading. As a result, items were
grouped within their respective factors. |
Criterion Validity |
| The Modified Stress Questionnaire by Konduri 12 was selected to be as cornerstone in
this study as it is the only precise measure for pharmacy students. Permission had
been taken from the corresponding author to use their questionnaire as gold standard.
The contribution made to the response format is adding the term ‘not exist’ to the “no
stress” option as well as amending some grammars to be: 0 = not stressful or not exist,
1 = little stressful, 2 = moderately stressful, and 3 = severely stressful. A total of 264
copies of the Modified Stress Questionnaire were answered by part of the index
students in addition to their response to the 40-items SALS in order to test the
criterion validity. Their selection from the total number (388) was random as well.
The Modified Stress Questionnaire which was administered in this study was 29-items
because we deleted one factor (3 items) related to environmental stress/world situation
which is not applicable to Malaysian students. |
Results |
| A self-reported demographic form was filled prior to the experimental session.
Identification of the sample was as follow: Of the participants, 46.4% (n = 180) were
Malay, 50% (n = 194) were Chinese, 3.6% (n = 14) were other indigenous. 31.4% (n
= 122) of the sample were males, and more than two thirds of the sample were
females 68.6% (n = 266). 98.7% (n = 383) of the sample were single, whereas 1.3 (n =
5) were married. 99% (n = 384) of the sample were not smokers, and 1% (n = 4) were
smokers. 111 (28.6%) students recruited from first year, 108 (27.8%) from the second
year, 87 (22.4%) students from the third year, and 82 (21.1%) students from the fourth
year of study in Pharmacy School. The mean BMI of the sample was 20.94 Kg/cm2
(SD = 3.45). Age of participants ranged from 18 to 23 years. Scores from both of the
used questionnaires were treated as ordinal data (0 – 3 coding) to allow use of
common parametric tests 42. |
| The first run of the factor analysis with principal component extraction revealed ten
factors with an Eigen value of higher than one. This explained 55.101% of the total
variance. None of the items had a coefficient value of less than 0.5 in the Anti-image
correlation matrix. Lack of significant correlation between the individual items
indicates the independence of each item to measure different area contributing to
stress. On the other hand, the significant correlations between factors to each other
suggested the integrity of the structure of SALS and relation of all factors to one
construct. |
| Table 2 represents the final set of factors with their items loading after applying all the
previously delineated criteria. Reliability is estimated using Cronbach’s alpha
coefficient. The total coefficient value was 0.86 which indicates a reliable tool with
acceptable internal consistency. The alpha for the components ranged from .701
(Achievement - Motivation related stress) to .501 (Clinical career related stress).
These values did not increase if deletion of any item occurs. |
| The data reduction analysis resulted in 7 components with 27 items remained. These 7
factors accounted for 52.762 % from the total variance explained. Factors, number of
items and means with the same order in the psychometric table are showed in table 3.
Total mean score of SALS was 1.185 (min = 0.30; max = 2.59) for the whole sample
(n=388). This reflects low stress of pharmacy students in USM as total population if
we consider the Round-off theory of approximation. The self-confidence component
revealed the highest concern among other contributing factors to stress in academic
life. |
| The criterion validity has been demonstrated by the significant correlation (r = 0.747;
Pearson’s correlation; n = 264) of the total scores between both of the used
questionnaires in this survey. Significant correlation among meaningfully similar
component (academic stress factor) of SALS and the Modified Stress Questionnaire
gives an evidence of the convergent validity in SALS. All the correlations within the
domains and with the total scores of both of the scales were significant at less than
0.01 level (n = 264; two tailed Pearson’s). These one-direction correlations refer that
all the components are related to one construct. Table 4 presents correlation between
SALS and all its factors with one factor of the Modified Stress Questionnaire in
addition to total score correlation. |
Discussion |
| The data was gathered through subjective perceptions towards self assessment of the
severity of situations and thoughts. The use of questionnaires as a method of data
collection in health care research increased in recent years 41, 60. |
| Although there is some common purport between different scales of stress which
designed for health care profession students, there is clear difference in applicability
for each population. Each group of students may have different challenges from other
according to the differences in their programs and needs. So if specific measure of stress is needed, it should be more detailed than being general scale so that real
outcome and magnitude of stress can result. |
| Trying to produce broad bank that can cover all detailed issues arise during academic
life as stress requires huge bulk of items. Besides, the priority and causal of stress may
be totally different between individuals. SALS identified seven dimensions of the
daily life activities of the pharmacy students in the school but if we hold each one
separated, we can find many special scales for it 61-63. Development of a standardized
measure provides the opportunity to increase our understanding of the pharmacy
academic-clinical life related stress. Items were generated in a way being applicable to
all years of pharmacy education as well as this concept perceived as affecting their
experience and career as clinical care advisor. If we want to deal with the clinical
training as separated purpose, Special scale has to be specified for forth year students
as they go for hospital training. This may justify the low reliability of the clinical
career related stress as it had been answered by all students of all years. The reliability
measure is as subjective as the factor analysis 54. Results collected from multi-race
sample may also affect factors reliability as well 64. Although most of the stress scales
include the financial stressors, SALS did not concern about economical status of
students because we believe that the financial issue is a family responsibility for the
degree student. |
| Deleting the items with low correlation coefficient value in the pilot stage delivered
the advantage of not seeing low coefficients in the main result. This study
recommends considering of running factor analysis during piloting even when the
number of cases is as small as 100. This will avoid meeting weak items to avoid
affecting the main exploratory factor analysis later on. This exception is happening
during validation of many of the most common used validated scales like BSI or
others 41, 65. |
| Exploratory factor analysis is a widely subjective analysis and may vary even between
the same subjects in time series. We ran an exploratory factor analysis with varimax
rotation following the same criteria used by the authors to test replication of their
findings. The investigation revealed not exact factor structure when using among
pharmacy undergraduate students. This may not be a necessity that the difference in
program or difference in culture and population is the key, but may be even when the
same population is being surveyed again, different outcome might appear. |
| The explained variance of the component is consequently 8.459%, 8.251%, 8.162%,
8.129%, 7.414%, 7.049%, and 5.298%. This proximity in values reflects the equal
ratio of contribution to the measuring construct. Re-nomenclature of these factors was
done based on the meaning content of items after difference in loading from the
theoretical construct. This gives evidence that stress parameter is wide enough to
generalize to as many items as possible and all are contributing to stress at the end. |
| Overall findings suggest that SALS provide reliable scores measuring stress in
academic life arising from different social, academic and clinical activities of
pharmacy undergraduate students. |
Conclusion |
| SALS has shown statistically acceptable level of reliability and validity. Since the
tested sample of respondents is from single university, a full representation of
Malaysain pharmacy students is might be doubtful. The available number of
pharmacy students at USM does not match the diverse real percentages of races in
Malaysia. It would be quite interesting to compare stress between universities to
identify the major affecting stressors for each. Despite its limitations, the study
identified stressors that appear to differ from those reported in previous studies. If
SALS needs to be a universal scale for pharmacy students all over the world, it
requires retesting to duplicate the results in similar Malaysian and International
pharmacy undergraduate population. |
| This scale permits the determination of the level of stress in pharmacy school life in
general and it is applicable to all years of study. Topics for further research have also
been identified, including the desirability of measuring stress levels physiologically
rather than relying solely on self-reports, and extending the study to other settings.
This can be reached by the physiological detection of general stress and compare it
with the results of SALS. |
Acknowledgement |
| Special thanks to Dr. Norzarina Mohd Zaharim/ School of Social Sciences/ USM.
Regards and thanks to Dr. Lynne Yong/ Clinical Psychologist/ Adventist Hospital-
Penang, and to Mr. T. Ramayah/ School of Management/ USM for their contribution
in validation of the tool. We would like also to thank all the pharmacy students who
participated in our study for their patience and support during the experimental
session. |
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