RESILIENCE AS A MODERATOR IN THE RELATIONSHIP BETWEEN BURNOUT AND SUBJECTIVE WELL-BEING AMONG MEDICAL WORKERS IN SERBIA DURING THE COVID-19 PANDEMIC MODERATOR

Background/Aim. During the ongoing COVID-19 pandemic, exhaustion and difficulties at work can seriously endanger the mental health of medical workers. The aim of this study was to examine whether resilience is a moderator of association between burnout and subjective well-being among medical workers at the time of the pandemic. Methods. The research was conducted on a sample of 521 medical workers (354 female), among whom were 245 physicians and 276 medical technicians. The average age of the respondents was 38.66 years. Data were collected using online questionnaires comprising of the Brief Resilience Scale, the Work Burnout Scale, the Short Subjective Well-being Scale, and the Sociodemographic Data Questionnaire. Regression and interaction analysis (by SPSS macro ''PROCESS 3.5'', author A. F. Hayes) was used for data analysis and processing. Results. The results show that burnout is a significant negative predictor of subjective well-being of medical workers (ß = -0.19; p <0.01), that resilience is a significant positive predictor of subjective well-being (ß = 0.40; p <0.01), and that the interaction of resilience and burnout is a significant positive predictor of subjective well-being (ß = 0.09; p <0.01). In subjects who had developed resilience at the level of +1 SD, the negative effect of burnout on subjective well-being was 2.8 times lower than in subjects who had resilience at the level of -1 SD. Conclusion. The findings of the study confirmed that resilience reduces the connection between burnout and subjective well-being, which is a significant argument that medical workers should be provided with resilience training programs in order to prevent burnout and preserve mental health during a pandemic.


Introduction
By the nature of their work, medical workers experience unpleasant and stressful situations. During the time of the COVID-19 pandemic, exhaustion and difficulties at work can seriously endanger the mental health of medical workers [1][2][3][4][5][6] . Even before the mentioned pandemic, high resilience was cited as a feature that enables medical workers to easily recover from various misfortunes at work, which can be acquired through an appropriate training program [7][8][9] . Resilience is also cited as a trait that can reduce the association 5 between burnout and mental health difficulties of health professionals [10][11][12][13] . The subjective well-being of medical workers is an important and positive aspect of their mental health. In this paper, it was examined whether the connection between burnout and subjective wellbeing among physicians and nurses decreases with a higher degree of resilience at the time of the pandemic.
As a personality trait, resilience refers to an individual's ability to return to a state of normal mental functioning after stressful or threatening events, without lasting negative consequences 14 . As an individual's capacity, resilience can be defined as the sum of all protective factors that act in such a way that an individual maintains or improves his or her mental health after circumstances that may cause severe distress or mental trauma.
Protective factors can be: 1) individual factors, such as ways of coping with stress, cognitive capacity and strength of character of the individual, 2) factors arising from the social network of the individual, such as emotional or material support provided by family or close friends, and 3) support from the wider community, such as support provided by state institutions, companies and social organizations. Resilience is closely related to subjective well-being. Generally speaking, people with a higher degree of resilience also have a higher degree of subjective well-being, and a lower degree of depression, anxiety, and negative self-evaluation 9,15 .
On the framework of the theory of subjective well-being, Diener emphasized the importance of happiness and life satisfaction for the mental health of an individual 16,17 . Burnout is chronic stress at work that adversely affects mental health and reduces employees' job satisfaction. Maslach and her colleagues defined the concept of burnout as a syndrome that encompasses the following dimensions: 1) emotional exhaustion related to the experience of lack of energy for work and loss of enthusiasm, 2) cynicism related to work -includes the experience of distancing from work and coworkers, as well as 6 diminishing the importance of their work; 3) the experience of reduced professional efficiency 19 . Kristensen and his collaborators identify the following types of burnout: personal burnout, which refers to the experience of fatigue and exhaustion in general in life, work-related burnout, and client-related burnout 20 . Physical and mental fatigue and exhaustion are the basis of each of these types of burnouts. Berat and her associates distinguish between two highly interrelated experiences within work-related burnout: work exhaustion and the experience of job frustration 21 . Previous studies indicate that burnout of health workers increased during the COVID-19 pandemic compared to the time before that pandemic 22,23 .
Studies suggest that in physicians, resilience and burnout are interrelated phenomena, with greater resilience implying less burnout, just as greater burnout implies weaker resilience 11,12 . Resilience acts as a factor that reduces anxiety in doctors at work, as well as their exhaustion at work 4 . Also, the studies indicate that a negative correlation between burnout and resilience also exists among medical technicians 13,24 . A higher degree of resilience in medical technicians implies better coping skills at work, a higher level of self-efficacy and better social support at work, a lower level of exhaustion at work, as well as a lower level of anxiety and depression 25,26 .
Studies conducted by Yu et al. 25 and Wang et al. 27 indicate that burnout during the COVID-19 pandemic is negatively correlated with the subjective well-being and mental health of medical workers.
The aim of this study was to examine whether resilience is a moderator of the relationship between burnout and the subjective well-being of medical workers. The following hypotheses are set: 1) burnout is a negative and significant predictor of subjective well-being, 2) resilience is a positive and significant predictor of subjective well-being, 3) the interaction of resilience and burnout is a significant positive predictor of subjective well-being. A theoretical model is assumed in which the negative correlation between burnout and subjective well-being decreases with a higher degree of resilience.
Although the problem of this research arose on the basis of a very extensive scientific material on resilience, subjective well-being and burnout, the assumed theoretical model is original in terms of variable positions, methods and time of testing. This research, 7 in addition to theoretical significance, could also have important practical significance when it comes to creating trainings that develop resilience among medical workers in order to prevent burnout and preserve subjective well-being during a pandemic.

Sample and procedures
We adopted a cross-sectional study design for this research. Inclusion criteria for our study sample were residents of Serbia aged 18 years, or older and in a medical profession (medical doctors, medical technicians/nurses). Exclusion criteria were minors, residents of other countries and members of any profession outside the medical field.
Since the research was conducted during the COVID-19 pandemic, the data were collected online, using the Google Forms platform, in the period from April 16, 2020 to May 2, 2020 in Serbia. The objectives of the research were explained to potential participants at the very beginning of the anonymous online questionnaire in Serbian.
Participation in the research was voluntary and with informed consent, and respondents were guaranteed confidentiality and anonymity of the obtained data. All data was protected, only the research team had access. Duplicate and inappropriate survey responses were excluded with a manual review of gathered data.

Measures
Resilience. A version of the Brief Resilience Scale validated by Slišković and Burić 29 was used to test resilience, and the original version of this scale was created by Smith and his associates 14 . According to the mentioned authors, the Brief Resilience Scale has a very good reliability, the Cronbach's alpha coefficient was above 0.8 in previous research.
The Brief Resilience Scale is one-dimensional and consists of 6 items. Items refer to 8 resilience, which is defined as the ability to recover from stressful or threatening events.
Three items speak in favor of resilience (eg: 3. It does not take me long to recover from a stressful event), while three items speak against resilience and have the opposite scoring (eg: 4. It's hard for me to snap back when something bad happens). Respondents had an option to choose one answer on a five-point Likert-type scale, from 1strongly disagree, to 5strongly agree. The total score on this scale is the arithmetic mean of all six items.
Resilience was treated as a moderator variable.
Burnout. Burnout was examined by the version of Work Burnout Scale given by Demographics. To collect data on gender, education and age, a questionnaire of sociodemographic data was developed by the authors of this research. Gender, age, and occupation were selected as covariates, as it has been done in previous research 1,9,10 .

Data Analysis
Mean values, standard deviations, minimum and maximum value, skewness and kurtosis were used as measures of descriptive statistics. To check the reliability of the scales used, the Cronbach's alpha coefficient was used as a measure of internal consistency.
Regression analysis and a special moderation analysis procedure created by Hayes 30 were used to test the set hypotheses. Free SPSS macro PROCESS 3.5 was used, which performs regression analysis by examining the significance of the interaction of moderator and focal predictor, as a predictor of the dependent variable, with the assessment of the significance of statistics in the usual way (using the value of p), but also with a special procedure called bootstrapping. Bootstrapping includes regression analysis on a large number of random subsamples (resampling), and in this paper the option is set to 5000. This appendix allows the program to analyze the relationship between focal predictors and dependent variables at different levels of moderators (conditional effects of focal predictor at values of the moderator). Since macro PROCESS 3.5 produces a printout that gives non-standardized predictor regression coefficients, before regression analysis, standardized variables were calculated that were used in the procedure to obtain standardized regression coefficients (ß) in the printout, because they are commonly used in the display of results, and for easier comparison of predictors.

Participant characteristics
The sample consisted of 521 medical workers, among them were 245 physicians and 276 medical technicians, 354 female respondents, among them 153 physicians and 201 medical technicians. Among the 167 male respondents, there were 92 physicians and 75 medical technicians. The average age of the sample was 38.66 (SD = 9.46) years. The age range of medical technicians ranged from 19 to 62 years, while the age range of physicians was 25 to 62 years. Table 1 shows measures of descriptive statistics and scale reliability. All instruments used in this study had a high reliability which was expressed as the α coefficient of internal consistency (Cronbach's alpha), as it was expected.

Table 1
Tables 2 and 3 show the results of regression and interaction analysis. These predictors explain 31% of the variance in subjective well-being.

Table 2
Covariatesage, gender and occupation (physician or medical technician) were not significant predictors of subjective well-being. Table 3   Table 3 shows the effects of burnout on subjective well-being at three different levels of resilience. At the low and medium level of resilience, burnout is a significant negative predictor of subjective well-being, while when resilience is expressed at a level of plus one standard deviation, the relationship between burnout and subjective well-being ceases to be statistically significant (p> 0.05, and CI includes zero). It can be clearly seen that with the increase in the resilience of the respondents, the connection between burnout and subjective well-being decreases, as the magnitude of the negative effects of burnout on subjective well-being decreases.

Discussion
The research findings confirmed the assumed model in which resilience is the moderator of the negative correlation between burnout and subjective well-being, so that the negative effect of burnout on subjective well-being among medical workers decreases with greater resilience.
Our results showed that burnout is a significant negative predictor of the subjective well-being of medical workers (ß = -0.19; p <0.01), which is in line with the results of previous research which indicated that burnout has a negative effect on mental health and the subjective well-being of medical workers 2,22,25,27 . Some other studies also showed that burnout is a significant negative predictor of subjective well-being 3, 10, 23, 27 . With more burnout, subjective well-being is lower. However, based on the confidence interval obtained based on the bootstrap procedure, it can be seen that the sample includes respondents who differ greatly in the degree of connection between burnout and subjective well-being, because the lower limit is 2.8 times lower than the upper limit (LLCI = -0.28 and ULCI = -0.10).
Exhaustion and frustration related to work are aspects of burnout [19][20][21] and these experiences are mutually conditioned with experiences of happiness and positive emotions in life, which are aspects of subjective well-being 16,17 . This finding indicates that burnout has a negative effect on subjective well-being, but also includes the possibility that the degree of subjective well-being affects the experience of burnout. Medical workers who experience their lives as difficult and unhappy find it easier to perceive their work as frustrating and exhausting.
In our study resilience is a significant positive predictor of subjective well-being (ß = 0.40; p <0.01), which is in line with previous research showing that resilience is a factor that has a positive effect on mental health and subjective well-being 9-12 . Greater resilience implies greater subjective well-being, and vice versa, with less resilience, subjective wellbeing is lower. Resilience is the result of all protective factors that act to keep an individual healthy in difficult circumstances 9,14,15 , so that subjective well-being can be understood as a consequence of resilience, but and as a factor of resilience. Developed resilience of medical workers, implies personal skills and other opportunities to maintain good mood, level-headedness and correct judgment after stressful circumstances [7][8][9] , which according to In our study the interaction of resilience and burnout is a significant positive predictor of subjective well-being (ß = 0.09; p <0.01); with greater interaction, subjective well-being is better. The contribution of this interaction, although statistically significant, is not large -in the regression model it contributes to the explanation of only 1% of the variance of subjective well-being. However, data on the confidence interval (CI) based on the bootstrap procedure indicate that the sample includes very different respondents according to the degree of connection between this interaction and subjective well-being, the lower limit of the confidence interval (LLCI = 0.02) is as much as 8 times lower than the upper limit (ULCI = 0.16).
Our study demonstrates that the negative association between burnout and subjective well-being among health care workers is significantly higher when they have low resilience. The negative effect of burnout on subjective well-being in subjects with a level of resilience at minus one standard deviation is 2.8 times higher than in subjects with a level of resilience at plus one standard deviation (see effect size in Table 3). This finding indicates that resilience prevents frustrations and exhaustion from work from worsening the degree of subjective well-being of medical workers.
These scales have not been used so far for examinations of medical workers in Serbia. However, for the sake of insight into the bigger picture, these results will be The design of this research does not allow the consideration of cause-and-effect relationships. The findings of this research do not exclude the possibility that there is an opposite direction of action in which favorable subjective well-being acts so that burnout is weaker and vice versa, that less favorable subjective well-being implies the experience of greater burnout. It has already been pointed out that subjective well-being can be understood both as a consequence and as a factor of resilience 9 , as well as in those studies where it is suggested that burnout is negatively correlated with worker resilience 4, 12, 24-26 .
It is possible that there is a circle in which the weakening of subjective well-being leads to weaker resilience, which leads to more difficulties and unpleasant experiences related to work, and this then adversely affects subjective well-being and resilience. The analytical moderation procedure applied in this study best corresponds to the experimental designs 30 , although the design of this study is not such, here in a creative and illustrative way this procedure is used only to show the correlation between the examined phenomena, without concluding causation-consequential relationships.
The age of medical workers was not a significant predictor of subjective well-being.
In addition to age, gender was chosen as a covariate variable because it was previously shown that gender could be a significant factor in mental health in health care workers 10 , as well as subjective well-being 15 . Compared to men, women as respondents in the research more often perceived their mental health as a little less favorable, and subjective well-being as somewhat lower. In a sample of this study, gender was not a significant predictor of subjective well-being. Also, in this study, a covariant variable called profession with two possible indicatorsphysician or medical technician, did not prove to be a significant predictor of subjective well-being, indicating that the difference in job type is not significantly related to subjective well-being in this sample.
The sample of this research does not allow generalization of the results so that it is valid for the entire population of medical workers. In addition, findings on burnout indicate that the COVID-19 pandemic most likely contributed to a significant increase in burnout levels of health workers compared to the time before the pandemic, as indicated by other studies 3, 6, 23, 27 . Therefore, it is also a possible condition that is a limitation for generalizing the results of this research, so that the findings are valid in circumstances of increased burnout.

Conclusion
The resilience of health workers is negatively associated with burnout, is positively correlated with subjective well-being, and mitigates the negative correlation of burnout and subjective well-being. The findings of this study represent a significant argument that medical workers should be provided with resilience training programs in order to prevent burnout and maintain mental health in a pandemic. Table 1 Descriptive statistics for resilience, burnout, and subjective well-being  Table 2 The predictors of subjective well-being