Note: Tables, appendix and figures
of the article can be accessed and seen in the PDF file.
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.
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 self-completion, 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.
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.
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.
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.
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.
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.
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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