Participants and data collection
The present cross-sectional study was carried out between March 5th to April 5th, 2020. We targeted all of health care worker that works in Iran ministry of health and medical education such as nurses, doctors, emergency medical service staffs, clinical, and public health technicians. Informed written consent was obtained from each participant. Then, the anonymous online questionnaires were distributed to them via social networks. Every health worker could fill the questionnaire only one time.
Questionnaires
Demographic Questionnaire
This questionnaire included Sociodemographic information such as age, marital status, sex, job title, shift working (fixed morning, fixed evening, fixed night or rotational), type of employment (contractual or permanent), number of over times per month, duration of employment (in years), educational level (diploma, bachelor's, master's, doctoral and higher), Governmental workplace (yes or no), facing with COVID- 19 patients at workplace (yes or no), interest in job (yes or no), Increased working hours due to COVID-19 prevalence (yes or no), ward of work ( ICU, operating room, laboratory, emergency, radiology, nursing station, COVID-19 service center or other).
NASA-TLX Questionnaire
To assess workload, we applied the NASA-TLX (NASA -Task Load Index) technique. This technique was developed by the Human Performance Group at NASA Ames Research Center and involved 6 subscales, including mental demands, physical demands, temporal demands, performance, effort, and frustration. Twenty step bipolar scales are used to obtain ratings for these subscales. The score of each scale is from 0 to 100. NASA-TLX score is calculated by multiplying each subscale rate to its weight. The overall workload is obtained by summing across scales and dividing by 15[11, 12]. Acceptable reliability of the NASA-TLX among health workers was indicated by Mohammedi et al. with Cronbach’s alpha = 0.897[13].
General health Questionnaire (GHQ-12)
To evaluate the mental health (the psychosocial well-being), the General Health Questionnaire-12 (GHQ-12) was applied. GHQ developed by Goldberg & Williams in 1972. This instrument had originally 60-item, but now there is a range of brief versions of the questionnaire, including the GHQ-30, the GHQ-28, the GHQ-20, and the GHQ-12. The GHQ-12 is short and easy to complete, and its application in research settings appropriate. The GHQ-12 comprises 12 items (six of which are positively phrased and six negatively phrased). Each item is responded to on a 4-point scale (less than usual, no more than usual, rather more than usual, or much more than usual). We used Goldberg's original scoring method (0, 0, 1, and 1). This method supplies scores ranging from 0 to 12[14]. Good reliability of Persian translation of the GHQ-12 was shown by Montazeri et al. study, with Cronbach’s alpha = 0.87[15].
Statistical Analysis
All statistical analyses were performed using IBM SPSS Statistics software (Version 23) (IBM SPSS Statistics, Armonk, USA). The normality of variables was confirmed using the Kolmogorov- Smirnov test. A chi-square test was used to compare the categorical data between groups. and was applied to compare parametric data between the groups. The comparisons of the variables difference between the groups were performed with the independent Student's t-test and ANOVA. Linear regression analysis in 3 models (Model 0, linear regression analysis without adjustment; Model I, linear regression analysis with adjustment for encounter to corona virus; Model II, linear regression analysis with correction for encounter to the corona virus, age, sex, marital, job, experience, type of employment, shift, education, governmental, interested, and ward of work) was used for determination of the association between overtime with total Task Load score and GHQ score. Moreover, Spearman- test was used for correlation between total Task Load score, NASA-TLX questionnaire components an GHQ score with age, education, and experience. A p-value of less than 0.05 was regarded to be statistically significant.