Study setting and participants
This cross-sectional online survey was conducted from 1 July 2020 to 21 July 2020, which was 3 weeks after the Malaysian government lifted the MCO (MCO was lifted on 11 June 2020). During the period of data collection, although the MCO had been lifted, the rate of spread of COVID-19 in the country was not fully under control, with the number of cumulative COVID-19 cases at 8840 cases and the number of deaths at 123 cases at the end of the data collection period . The sample size was calculated based on the formula:
n= [(Z1-α/2 x ϭ)/∆]2 (where n was the total estimated sample size, Z1-α/2 was the value represented the desired confidence interval in which confidence level selected was at 95% with a critical value of 1.96, ϭ was standard deviation which was 18.2 based on the QoL of the general population , and ∆ was precision with a value of 2.5). Hence, the estimated sample size needed was 243 subjects (after considering an additional 20% of sample loss). Recruitment of study participants was carried out by snowball sampling from the medical faculties of Malaysian public university students in Klang Valley at the Central of Peninsular Malaysia and in the states of Penang and Kelantan located at the northern region of Peninsular Malaysia. Initially, the online survey was disseminated to medical postgraduate students and they were told to circulate the invitation to participate in the survey to other medical postgraduate students, medical undergraduate students, postgraduate and undergraduate students in medical sciences and other students within the medical faculties of public Malaysian universities located at the targeted regions. We selected participants with a diverse range of demographic characteristics according to age, gender and marital status. The study was approved by the Human Research Ethics Committee of USM (USM/JEPeM/COVID19-21) and the Medical Research Committee of the Faculty of Medicine, UKM (UKMPPI/111/8/JEP-2020-370). Those who were 18 years and above, registered as students with the Faculty of Medicine of Malaysian public universities located in Klang Valley and the states of Penang and Kelantan in Peninsular Malaysia, were eligible to participate in the study. Those who presented with psychotic disorders, bipolar mood disorder or a history of illicit drug use were excluded from the study. All the participants provided informed consent, and they were assured of anonymity and data confidentiality. They completed the questionnaires through an online survey platform (Google Forms). Initially, a total of 381 participants responded to the online survey. We excluded 65 participants who took less than 60% of the median time to complete the questionnaires in this study (median time= 15 minutes) to avoid any response bias. Double responses from the same participant were prevented by activating the “limiting responses to once per person” function in Google Forms. The final sample size of the study was 316 participants.
A self-report questionnaire was administered to the participants to collect data on the following: demographic and personal characteristics, clinical factors, and COVID-19 related stressors and coping of the participants. The self-reported questionnaire was constructed based on previous surveys on the psychological impact of the SARS and MERS epidemics on university and medical students [12-16]. The participants were also administered the Malay version of the 21-item depression, anxiety and stress scale (DASS-21) to assess the severity of their depressive, anxiety and stress symptoms; the Malay version of the multidimensional scale of perceived social support (MSPSS) to assess the degree of social support; and the Malay version of the WHOQoL-BREF to assess QoL. In this study, the DASS-21 subscale scores, MSPSS domain scores and WHOQoL-BREF domain scores were presented as continuous variables.
Data on demographic characteristics of the participants collected in this study included age, gender, marital status and monthly living expenses. The assessment and coding for demographic characteristics are summarized in Section 1 of the Supplementary material.
The personal characteristics assessed in this study were types of courses enrolled in university and living arrangement. The assessment and coding for personal characteristics are summarized in Section 1 of the Supplementary material.
Data on two clinical factors were collected in this study, which were history of pre-existing medical illnesses and history of pre-existing depressive and anxiety disorders. The assessment and coding for clinical factors are summarized in Section 1 of the Supplementary material.
COVID-19 related stressors and coping
Data on COVID-19 related stressors and coping included in this study were hours of online classes attended per week, perceived prevalence of COVID-19 cases at place of living, frustration because of loss of daily routine, frustration because of disruption of study and use of religious coping to manage stress in response to the COVID-19 pandemic. The assessment and coding for COVID-19 related stressors and coping are summarized in Section 1 of the Supplementary material.
Depression, anxiety and stress
The presence of depression, anxiety and stress as well as the severity of these symptoms were evaluated with the DASS-21. The DASS-21 is a self-report questionnaire consisting of 21 items, with 7 items per subscale; the subscales are depression, anxiety and stress. Each item is scored on a Likert scale from 0 (did not apply to me at all) to 3 (applied to me very much). Sum scores are computed by adding the scores on the items per subscale and multiplying them by a factor of 2. Sum scores for each of the subscales may range between 0 and 42. Hence, the total score of the DASS-21 ranges from 0 to 120. The cut-off scores for case findings in DASS-21 are as follows: 9 for the depression subscale, 7 for the anxiety subscale and 14 for the stress subscale . The Malay version of the DASS-21 has good Cronbach’s alpha values of 0.75, 0.74 and 0.79 for the depression, anxiety and stress subscales, respectively .
The perceived social support received from family, friends and significant others were measured by the MSPSS. The MSPSS is a self-administered instrument that measures the perceived adequacy of the available amount of social support individuals receive from friends, family and significant others/special persons. The MSPSS has 12 items, where each item is rated on a 7-point Likert scale ranging from 1 (very strongly disagree) to 7 (very strongly agree). Hence, the cumulative scores of the MSPSS range from 12 to 84. Each domain comprises four items; hence, the cumulative scores for each domain range from 4 to 28. The higher the score, the higher the level of perceived social support of the individual. The original version of the MSPSS has good internal consistency (Cronbach’s α = 0.88) . The Malay version of the MSPSS has been validated among Malaysian university students, showing a high internal consistency (Cronbach’s α = 0.94) .
Quality of life
The quality of life of the participants was measured by the WHOQoL-BREF. The WHOQoL-BREF is a self-administered questionnaire that was used to assess the QoL of the subjects. It comprises 26 items; items 1 and 2 are general questions on QoL, whereas the other items are grouped into four domains (i.e. physical health, psychological, social relationship and environment-related QoL. Each item is scored on a Likert scale ranging from 1 to 5. Each domain is scored with values from 0 to 100, with higher scores indicating better QoL. The WHOQoL-BREF has good psychometric properties . The general norms for the WHOQoL-BREF domain scores are as follows: 70.6 (standard deviation = 14.0) for psychological QoL, 73.5 (standard deviation = 18.1) for physical health QoL, 75.1 (standard deviation = 13.0) for environmental QoL and 71.5 (standard deviation = 18.2) for social relationships QoL . The Malay version of the WHOQoL-BREF has also demonstrated excellent psychometric properties, with an internal consistency (Cronbach’s α) of 0.89 .
Statistical analyses were performed with the Statistical Package for Social Sciences (SPSS) version 26 (SPSS 26; SPSS Inc., Chicago, Illinois, USA). Descriptive statistics were reported for demographic, personal, clinical factors and COVID-19 related stressors and coping of the participants, as well as for the DASS-21, MSPSS and WHOQoL-BREF domain scores (to achieve objective 1 of the study). All the categorical variables were presented as frequencies and percentages, while the continuous variables were presented as means and standard deviations. There were no missing data.
To achieve objective 2 of the study, simple and multiple linear regression analyses were used to examine the association between COVID-19 related stressors and coping, psychological factors, perceived social support and quality of life domains. In the multiple linear regression analyses, we adjusted relevant demographic, personal, and clinical variables. Multicollinearity was assessed by referring to the variance inflation factor, in which all the independent variables included in the multiple linear regression models had a score of < 5, indicating no multicollinearity. The normal probability plot of residuals of all the multiple linear regression models demonstrated that all the points lay in a reasonably straight diagonal line from bottom left to top right, indicating that the errors of the linear regression models were normally distributed. Statistical significance was set at p < 0.05 for the multiple linear regression analyses, and all p-values were two-sided.