Anxiety Levels among Polish and Turkish Dentists during the COVID-19 Pandemic

Working conditions, work-related stressors and high risk of infection, as well as the fear of contagion and spreading the disease to family members, may have influenced dentists’ mental health during the COVID-19 pandemic. The aim of this study was to evaluate the anxiety levels among Polish and Turkish dentists during the COVID-19 pandemic and to investigate any relevant predictors. The study was an anonymous online questionnaire-based cross-sectional study that was conducted among dentists from two countries: Poland and Turkey. In total 400 dentists (200 from each country) participated in the study. The survey consisted of two parts: part 1 comprised demographic data, including age, gender, country of origin, COVID-19 infection history, place of work and lockdown history; part 2 was based on the State–Trait Anxiety Inventory (STAI). The mean trait and state anxiety levels of the Polish dentists was statistically significantly lower than that of the Turkish dentists (p = 0.000; p < 0.05). However, Polish dentists had higher state anxiety levels than trait levels, while both types of anxiety among Turkish dentists were almost at the same level. The number of dentists who suffered from COVID-19 was found to be statistically significantly higher in Poland (54%) than in Turkey (16%) (p = 0.000; p < 0.05). The percentage of dentists reporting anxiety was 51% in Poland and 95.5% in Turkey. Polish dentists reported a lower mean anxiety level during the COVID-19 pandemic than the dentists in Turkey but their anxiety levels were more affected by the COVID-19 pandemic as they had a higher difference between their state and trait anxiety levels. The higher coronavirus infection rate and lack of governmental lockdowns of dental practices during the pandemic in Poland compared with those in Turkey may explain the difference in the state and trait anxiety levels.


Background
Since the World Health Organization (WHO) declared the spread of coronavirus disease 2019 (COVID-19) a pandemic, healthcare institutions have prioritized critical patient care in order to reduce viral transmission and testing [1]. Meanwhile, lockdowns, isolation, fear of disease, economic recession and job loss were also negatively affecting the mental health of many people [2,3]. A high number of individuals reported that stress over COVID-19 led to specific negative impacts on their wellbeing, such as the difficulty in sleeping or eating and worsening of chronic conditions. Numerous studies have also shown that among the COVID-19 mental health consequences, anxiety and depressive disorders played a crucial role [4][5][6][7][8][9][10][11][12].
Anxiety is a normal reaction to uncertainty and in the short term prepares an individual to face an intense situation by increasing breathing and heart rate, as well as blood flow to the brain. However, an excessive or persistent state of anxiety can have a devastating effect on physical and mental health. Symptoms of an anxiety disorder may begin immediately

Objectives
The aim of the study was to evaluate the anxiety levels of Polish and Turkish dentists during the COVID-19 pandemic and to investigate any relevant predictors. The main research objective was to investigate whether the COVID-19 pandemic correlated with the anxiety levels of dentists and to analyze the eventual differences between nationalities and the different conditions affecting the dentists during the pandemic.

Study Design
The investigation was an anonymous online questionnaire-based cross-sectional study conducted among dentists from two countries: Poland and Turkey. It was performed in accordance with the Public Opinion Research Guidelines and based on the computerassisted web interview methodology. Ethical approval for this study was obtained.

Participants
The study was conducted among dentists: 200 in Poland and 200 in Turkey. Participation was voluntary and participants were allowed to terminate the survey at any time. Confidentiality and privacy were protected according to general data protection regulations. The study was conducted from 9 to 12 July 2021 and had a total of 400 respondents, 162 (40.5%) men and 238 (59.5%) women, aged between 23 and 67 years. The mean age of the dentists was 42.39 ± 9.99 years.

Data Collection
Online social media platforms, Facebook and Twitter, were employed for sampling. The survey was posted in the form of a link to a questionnaire that was to be filled in directly by a person willing to participate. The link was placed in professional social media groups (in which members were subject to prior verification confirming their dental licenses) and only to groups that allowed posting of this type of content.

Questionnaire
The survey consisted of two parts. Part 1 comprised demographic data, including age, gender, country of origin, COVID-19 infection history, place of work (private, public, mixed) and professional COVID-19 related lockdown information: governmental or other reasons (Appendix A, Table A1). Participants were asked if they had performed at least one COVID-19 test and if they had received at least one positive COVID-19 test result. They were also asked whether they had experienced any COVID-19 symptoms during the pandemic. Part 2 was based on the State-Trait Anxiety Inventory (STAI) [33,40]. STAI is a questionnaire-based psychological tool, which consists of 40 questions to be answered on a self-reporting basis. Answers are based on a 4-point Likert scale (1-not at all, 2-somewhat, 3-moderately, 4-very much). STAI measures two types of anxiety using subscales with 20 items each. State anxiety (anxiety about an event) assesses how the respondents felt during a stressful situation or a particular event and trait anxiety (anxiety as a personal characteristic) evaluates how they feel in general. The state anxiety subscale includes statements such as: "I am tense", "I am worried", "I feel calm", "I feel secure". There are phrases such as: "I worry too much over something that really doesn't matter" and "I am a steady person" among the trait anxiety items. The range of scores for both of the subscales varies from 20 to 80, and a higher score indicates greater anxiety. A cut-off point of 39 has been suggested to detect clinically significant symptoms of anxiety and the comparison between subscale results enables the assessment of the difference between anxiety as a personal characteristic and anxiety caused by an event.

Statistical Methods
Continuous variables were summarized byt mean, standard deviation and frequency. Categorical variables were summarized by number and percentage of occurrences for each possible value. In order to obtain an effect size of 0.5 for determining the difference in numerical variables between two measurements, with the level of significance set to 0.05 and the power set to 0.9, the calculated minimum required sample size was 186 subjects per group. Normality was checked using the Shapiro-Wilk test. Yates' correction was applied to prevent overestimation of statistical significance differences in numerical variables between the independent groups that were tested with a 95% confidence interval (CI). Significance was evaluated at the p < 0.05 level. The Student's t test was used for the comparison of normally distributed parameters (quantitative data) between two groups, while the paired Student's t test was applied for the comparison of the two types of anxiety. The Chi-square test was used to compare qualitative data. Correlation between two quantitative variables was assessed using the Pearson correlation coefficient (if both variables were normally distributed) and with the Spearman rank correlation coefficient (otherwise). Strength of relationship was interpreted as follows: |r| ≥ 0.9-very strong correlation, 0.7 ≤ |r| < 0.9-strong correlation, 0.5 ≤ |r| < 0.7-moderate correlation, 0.3 ≤ |r| < 0.5weak correlation, |r| < 0.3-very week correlation, according to interpretation schema by Hinkle et al. [41]. Multivariate logistic regression was performed at the level p < 0.05, with a 95% confidence level (Cl) and cut-off point for clinically significant anxiety equal to 39. All the calculations were performed in IBM SPSS Statistics 22 (IBM SPSS, Turkey).

Ethics
The study was performed in accordance with the Helsinki Declaration and official approval from the Jagiellonian University Ethics Committee was obtained (No.1072.6120.158.2021).

Results
Cronbach's alpha reliability factor for state anxiety on the STAI subscale was 0.86 in Poland and 0.84 in Turkey, while for trait anxiety on the STAI subscale it was 0.84 in both countries. The number of "survey invitation" social media post views and number of completed surveys within the study period were used to calculate the response rate, which was 71.5% for Poland and 74.3% for Turkey.
General evaluation of study parameters across both countries is presented in Table 1. There was no statistically significant difference between Poland and Turkey in terms of gender (p > 0.05) and being tested for COVID-19 (p > 0.05). A total of 91.5% of positive COVID-19 test results among 59% of the tested dentists in Poland was found to be statistically significantly higher than in Turkey (24.1% of positive COVID-19 test results among 66.5% of tested respondents). The COVID-19 pandemic dental office lockdown count in Poland (0%) was found to be statistically significantly lower than in Turkey (59.5%). The dentists had to stop working temporary during the COVID-19 pandemic due to reasons other than lockdown (lack of protective supplies, COVID-19 infections, quarantine, etc.) more frequently in Poland (93%) than in Turkey (21%). In addition, the number of dentists who suffered from COVID-19 was found to be statistically significantly higher in Poland (54%) than in Turkey (16%). A total of 49.5% of infected dentists in Poland predicted that they were infected at work in comparison to 4.5% of Turkish dentists who suffered from COVID-19. On the contrary, 54% of dentists in Turkey stopped working due to the fear of infection, while in Poland only 13% of dentists were too afraid of contagion to decide to stop working.
Evaluation of state and trait anxiety levels across both countries is presented in Table 2. Polish dentists presented mean trait and state anxiety levels that were statistically significantly lower than the Turkish ones (p = 0.001; p < 0.05); however, Polish dentists had a higher state anxiety level than trait anxiety level, while both types of anxiety among Turkish dentists were almost at the same level.
Evaluations of the state and trait anxiety scores using different factors separately for Poland and for Turkey are presented in Tables 3 and 4. Spearman correlations are presented in Tables A2 and A3.
Separate evaluation of the anxiety ranges for Poland and Turkey did not reveal statistically significant differences between the state and trait anxiety mean scores between dentists with and without a positive COVID-19 test result in Poland (p > 0.05) but such a difference existed among respondents in Turkey for the trait anxiety scores (p = 0.022). A similarity was observed in the correlation between both state and trait anxiety levels and the break at work caused by the COVID-19 pandemic. Anxiety level was found to be statistically significantly higher among dentists who had to stop working, than among those who did not have any breaks at work during the pandemic (  Multivariate logistic regression of state and trait anxieties among Polish and Turkish dentists is presented in Tables 5-8. Independent predictors of the odds of clinically significant state anxiety among Polish dentists are as follows (Table 5) Independent predictors of the odds of clinically significant trait anxiety among Polish dentists are as follow (Table 6) None of the variables analyzed by multivariate logistic regression were statistically significant independent predictors of the odds of clinically significant trait and state anxieties among Turkish dentists (Tables 7 and 8).

Discussion
Our study reported that Polish dentists had higher state anxiety levels than trait anxiety levels, while both types of anxiety among Turkish dentists were almost at the same level. This might suggest that the state of the pandemic raised anxiety levels among Polish dentists more Turkish dentists. Several factors that were estimated in the study might explain the difference between the two countries. First of all, although a similar number of dentists in both countries were tested for COVID-19 (59% in Poland and 66.5% in Turkey), the number of positive test results was much higher in the Polish group (91.5% vs. 24.1%). In addition, the number of dentists who suffered from the COVID-19 symptoms was found to be higher in Poland (54%) than in Turkey (16%).
Evidence from previous pandemics showed that a lot of people were at risk of developing mental health disorders due to the COVID-19 pandemic, such as depression, anxiety, or sleep disturbances [13][14][15][16][17][18][19]. In a systemic review of the mental health status of patients during the COVID-19 pandemic the prevalence of depression was found to be 48%, which was higher than the pre-pandemic depression levels (5-34%) [25]. Additionally, the prevalence of anxiety and sleep disturbances among COVID-19 patients was reported to be higher than in the general population (31.9% and 20.1%, respectively) [42]. Recent studies have suggested that these disorders should be adequately investigated and addressed by clinicians in order to improve prognosis and avoid long-term mental health issues [5][6][7][8][9][10][11][12]. Therefore, there is a need for developing appropriate methods and tools for diagnosing mental health disorders associated with the pandemic. A recent study reported that anxiety especially should be carefully investigated and the work even suggested a new scale: the Coronavirus Anxiety Scale (CAS) [43].
Healthcare workers were one of the groups of people that were most affected by the pandemic; hence, they may present many different mental health problems as a consequence of it [44][45][46][47][48]. In one a study conducted in Turkey, the mean state anxiety score among emergency medical service professionals during the COVID-19 pandemic was 50.7 ± 11.6 [49], which was similar to our results (45.07 ± 10.94). As the state and trait anxiety scores may vary from 20 to 80, a cut-off point of 39-40 was suggested in order to detect clinically significant symptoms of anxiety [33,40]. In our study Polish dentists presented mean trait and state anxiety levels that were lower (39.09 ± 12.7, 42.64 ± 13.68) than the dentists in Turkey (47.09 ± 4.96, 47.49 ± 6.42), however both groups achieved levels over the cut-off point, which suggested clinically significant anxiety. Similar outcomes confirming the impact of the pandemic on the mental health of healthcare providers, and the higher stress and anxiety levels, has already been well documented in different studies during previous pandemics [13][14][15][16].
According to previous studies [17,36], we could expect a higher level of anxiety among infected individuals, thus the higher COVID-19 infection rate might be an explanation for the increased levels of state anxiety among Polish dentists versus the equal levels of state and trait anxieties in Turkey, where the infection rate was much lower. Secondly, the results revealed that as there was no governmental lockdown of dental practices in Poland (0%), compared with Turkey where the governmental lockdown affected 59.5% of dentists, the dentists in Poland worked longer in the pandemic conditions and experience more stress. Moreover, longer exposure to the contagious environment might have also been a factor in the higher infection rate among Polish dentists. Additionally many dentists in Poland (93%) had to stop working temporarily during the COVID-19 pandemic due to reasons than other lockdown, such as the lack of protective supplies, COVID-19 infection and quarantine, for example, which increased working stress factors. Multivariate logistic regression of the current study revealed that COVID-19-related breaks at work raised the possibility of clinically significant state anxiety among Polish dentists by a factor of 9.128. Finally, 49.5% of dentists in Poland who suffered from COVID-19 predicted they were infected at work in comparison to 4.5% of Turkish dentists. It has already been reported that the dental care environment carries the danger of contagion for dental professionals and, thus, the awareness of such risk may lead to stress and fear, especially in the pandemic circumstances [50]. Another study that demonstrated cross-sectional data of fear and anxiety among dental practitioners during the COVID-19 pandemic revealed that the high level of fear among dentists was explained by the high probability of close interaction with COVID-19 positive patients while they were treating them and by the awareness of the disease and its mortality [51].
Evaluating the anxiety ranges of our study separately for Poland and Turkey, we may observe less statistically significant correlations between some factors and anxiety in comparison to general analysis. There was no statistically significant differences between the state and trait anxiety mean scores between dentists with and without a positive COVID-19 test result in Poland (p > 0.05); however, such a difference existed among respondents in Turkey. State anxiety among Turkish dentists with positive COVID-19 test results was higher than those with a negative one. Moreover, Turkish dentists who suffered from a COVID-19 infection also presented a strong correlation and higher state and trait anxiety scores than Polish dentists who suffered from the disease. In the separate analysis for each country, a similarity was observed in the correlation between both state and trait anxiety levels and the break at work caused by the COVID-19 consequences. The anxiety level was found to be statistically significantly higher among dentists who had to stop working than among those who did not have any breaks at work during the pandemic. A recent study found that more than three-quarters of dental practitioners (78%) from 30 countries (including Poland and Turkey) were anxious and scared by the devastating effects of COVID-19 [50]. In our study 54% of dentists who took part in the survey in Turkey stopped working due to the fear of infection. Another study reported that 71.9% of questioned dental care providers were anxious about contagion and 85.4% of them revealed a fear of infecting others. Moreover, respondents, who were constantly working during the pandemic, felt significantly more stressed about the possibility of infection while reporting that their workplaces handled the outbreak well (80%) [52]. The results of our study demonstrated that a break at work caused by the fear of COVID-19 infection elicited a statistically significant higher level of state and trait anxieties among Polish dentists.
Many recent studies have reported similar findings regarding the psychological consequences of the COVID-19 pandemic for dental health professionals. The prevalence of anxiety among frontline dental staff was reported to be 46.4% in a study by Chen et al. [30]. In another study 42.5% of dentists had COVID-19-associated anxiety and 35% of them had general health disorders [28]. Gasparro et al. [27] indicated that job insecurity and fear of COVID-19 were positively associated with depressive symptoms among dentists. In an online questionnaire-based survey assessing the level of perceived stress among dentists (before the COVID-19 pandemic and immediately after the nationwide lockdown was announced) the increase was noticed: the level of perceived stress rose from 18.61 to 20.72 during the outbreak (PSS-perceived stress scale) [29]. Before the pandemic having no family time due to long working hours (90%) was the major stressor among dentists, while concerns about getting infected (83.3%), followed by stress over financial implications were identified as the most frequent stressors during the outbreak. In the review by Sharma et al. [26] the psychological consequences were discussed in detail to highlight the challenges dentists were facing during the pandemic. According to the authors, compromised mental health was an important area that requirds attention during the COVID-19 outbreak.
The obtained results revealed that Polish and Turkish dentists experienced mental health issues during the COVID-19 pandemic with slight differences among the evaluated factors; however, regardless the factors and the way the data was analyzed, the anxiety levels remained high and over the cut-off point in most cases. A safe working environment and adequate infection control were important factors in securing less fear and anxiety. The long-term high level of anxiety among dentists may lead not only to significant economic implications but also to mental health disorders. Thus, in the situation of fear and anxiety caused by the pandemic, it was important to provide the adequate psychological coping mechanisms and strategies for diagnosing and maintaining mental health. Measuring anxiety levels and analyzing the related factors seemed to be useful tools in diagnosing and coping with the mental health disorders during pandemic.
The study has several limitations. First of all, it was carried out in two countries and, due to the COVID-19 pandemic, in an online form. This, and also the small number of respondents, may have limited t the generalization of the results. Furthermore, the as State and Trait Anxiety Inventory consists of 40 questions, in order to keep the survey relevant and not too overwhelming, only a few selected influencing factors out of many were included in the study. Additionally, our research was conducted in a short period of time and, thus, it did not examine the influence of the dynamics and duration of the pandemic on measured parameters. Additionally STAI assessment relies only on self-perceived data, which have a strong subjective component in the way answers have been resolved by the patient. As a non-probabilistic sampling method was used (the survey was posted as an open invitation on social media within a verified group of professionals) the calculation of a response rate, as well as the number of potential readers, was based on the number of post reads and completed surveys within the study period. However, as we did not have any basic information about the dentists who read the post but did not take part in the survey, the selection bias may have had an influence on the study estimates. Finally, although the authors identified the survey goals and clearly defined requirements for the target audience to the best of their ability, it was very difficult to estimate how representative the study participants were for all dentists in Poland and Turkey. Further longitudinal studies on a larger group of respondents, and in many countries, would definitely provide more detailed data.

Conclusions
The present study reported that Polish and Turkish dentists were suffering from anxiety during the COVID-19 pandemic. The study revealed that dentists in Poland were more mentally affected by the COVID-19 pandemic than Turkish ones, which might have been caused by a higher coronavirus infection rate. Lack of governmental lockdowns of dental practices during the outbreak in Poland, contrary to Turkey, may also have explained the higher level of anxiety due to the long-term exposure to hard working conditions. The stress at work seemed to be greater for Polish dentists as many of them had faced a temporary practice closure due to other pandemic related factors, such as the lack of protective supplies, COVID-19 infection and quarantine. Finally, the research confirmed previous reports of a high rate of fear of being infected at work. More studies could be effective in analyzing factors influencing anxiety among dentists during the pandemic.  Informed Consent Statement: Informed consent was obtained from all subjects involved in the study.

Data Availability Statement:
The data presented in this study are available on request from the corresponding author. The data are not publicly available due to ethical restrictions.

Conflicts of Interest:
The authors declare no conflict of interest.