Mental health among healthcare workers during COVID-19 pandemic in Thailand.

OBJECTIVES: This study aimed to measure the prevalence of burnout syndrome, anxiety, depression, and post-traumatic disorders (PTSD), as well as examine their associated factors among Thai healthcare workers (HCWs) during COVID-19 outbreak.
METHOD: We employed a multiple-method design at a tertiary-care hospital in Bangkok between May 22, 2021 and June 30, 2021 by using an online survey. The information included demographic characteristics, work details, perceived support, PTSD symptoms, Maslach Burnout Inventory: General Survey (MBI-GS), General Anxiety Disorder-7 (GAD-7), Patient Health Questionnaire (PHQ-2 and PHQ-9), and narrative response to an open-ended question. The associated factors of mental health problems were analysed by multiple logistic regression analyses. The qualitative data were analysed by the content analysis method.
RESULTS: A total of 986 HCWs (89.1% female; mean age = 34.89 ± 11.05 years) responded to the survey. 16.3%,16%, and 53.5% of respondents had a high level of emotional exhaustion, depersonalisation, and diminished personal achievement, respectively. 33.1%, 13.8%, and 2.3% of respondents had anxiety, depression, and PTSD. Risk factors of emotional exhaustion were male sex (ORadj = 2.29), nurses (ORadj = 3.04), doctors (ORadj = 4.29), working at COVID-19 inpatient unit (ORadj = 2.97), and working at COVID-19 intensive care unit (ORadj = 3.00). Additionally, preexisting mental illness was associated with anxiety (ORadj = 2.89), depression (ORadj = 3.47), and PTSD (ORadj = 4.06). From qualitative analysis, participants reported that these factors would improve their mental health: supportive and respectful colleagues, appropriate financial compensation, reduced workload, clarity of policy and communication channel, and adequate personal protective equipment.
CONCLUSIONS: Thai HCWs experienced negative mental health outcomes during the COVID-19 pandemic substantially. This issue needs attention and actions should be implemented to support them.

Introduction

The COVID-19 pandemic has been a challenge to all populations and public health systems around the globe. Since the World Health Organization declaration in March 2020 [1] the pandemic situation has been fluctuating, and the crisis has yet to be fully resolved.

It has impacted not only lifestyles, the economy, and physical health but also the mental health of individuals. High rates of psychological distress, stress, anxiety, depression, and post-traumatic stress disorder (PTSD) were reported in general populations in many countries in middle-income countries and higher-income countries on different continents [2-4]. However, prompt government implementation of stringent measures reduced the depression rate [5]. Among the middle-income countries, Thailand had the highest degrees of adverse mental health in the general population [6]. Physical symptoms suggesting COVID-19 infection were positively associated with high mental health outcomes [3]. Vice versa, having an underlying mood disorder increases the risk of COVID-19 hospitalisation and mortality [6].

In Thailand, since its first documented COVID-19 case in January 2020, the situation has continued to worsen even though Thailand was considered to be efficient in containing the COVID-19 in its early stage of spread [7]. To demonstrate, since the third wave of the outbreak in Thailand in April 2021, the number of accumulative COVID-19 cases has been increasing continuously. On April 30, 2021, there were 62,153 confirmed COVID-19 cases, and by the end of June 2021, the number rose to 259,301, most of which were in the Bangkok Metropolitan Region [8]. Healthcare systems are also varying between countries. During this study period, Thailand has not implemented a home isolation protocol, and all patients with COVID-19 were admitted to hospitals or ’Hospitels’, a government-run medicalised hotels for COVID-19 patients.

The pandemic impacts the work routines, work-related stress, and personal life of healthcare workers (HCWs) [9]. They are at higher risk of exposure to COVID-19 infection [10], in which doctors reported as more likely to exposure than nurses [11]. Extended working hours during the pandemic could lead to burnout and other adverse psychological problems. The psychological outcomes of HCWs during the pandemic have been studied globally. Common problems consisted of burnout syndrome, anxiety, depression, and PTSD [12-23]. Pooled prevalences of anxiety, depression, acute stress, post-traumatic stress are 30.0, 31.3, 56.5, and 20.2% respectively [18]. Studies in Asia showed the varied proportions of these problems in each country; anxiety 8.7–90%; depression 0.8–58%; post-traumatic stress 2.1–9.1% [19-22]. The pooled prevalences of anxiety and depression among East Asia countries are 20.5 and 19.1%, respectively [23]. With these psychological health impacts, not only will healthcare ’workers’ well-being be undermined, but their decision-making skills that involve patients’ care will be compromised. These unpleasant conditions will eventually affect not only patients but also society as a whole.

A number of studies also identified associated factors of negative mental health outcomes among HCWs. Regarding burnout, studies identified risk factors of burnout, including younger age, high workload [13], occupational factors, gender differences, [14] working on frontlines [15], shortage of resources [16]. Regarding associated factors of anxiety, depression, and PTSD among HCWs, results are inconclusive. However, potential risk factors include younger age, female, working frontline, lack of personal protective equipment, nurse or doctors, knowing someone who died of COVID-19, and lack of support were found to be associated in several studies [24-29]. Studies in Asia also revealed non-medical HCWs, physical symptoms, pre-existing medical conditions, and old age are more likely to experience negative mental health outcomes [10, 19–21]. To our knowledge, even though there was a study in Thailand found that 42.5% of healthcare workers had anxiety [30], there has yet to be a study on burnout syndrome, depression, and post-traumatic disorders among healthcare workers in Thailand. Furthermore, the COVID-19 pandemic situation changes continuously, and healthcare systems are specific to their countries. Therefore, we aim to measure the prevalence of burnout syndrome, anxiety, depression, and post-traumatic disorders, as well as their potential risks and protective factors among Thai healthcare workers during the ongoing third wave of COVID-19 outbreak in Thailand. Furthermore, the qualitative part aims to explore healthcare workers’ perspectives on factors that can improve their mental well-being.

Method

Study design, setting and participants

This study, conducted between May 22, 2021 and June 30, 2021, employs a multiple-method research design by using an online survey to gather quantitative data and narrative responses from an open-ended question. Inclusion criteria were healthcare workers working in any position at a tertiary-care hospital in Bangkok, which has been the center of the pandemic in Thailand. Hospital services relevant to COVID-19 treatment were medical evaluation for people at risk, inpatient units, intensive care units, and medical services at a Hospitel a new medical term that refers to a medicalised hotel for COVID-19 patients to receive treatment and recover.

Regarding participants, the proportions of healthcare workers with burnout syndrome, anxiety, and depression during the COVID-19 pandemic were estimated to be 0.34 [13], 0.41 [12], and 0.31 [12]. With error (d) = 0.05 and a finite population of 3218, the required sample size was 334 [31]. Research participants were approached through LINE application, the main social media platform connecting all healthcare workers of the hospital together. The convenience-based sampling method was used and the data were collected using Google Forms software. All participants were informed of the study’s objectives, method, and a consent statement before starting the survey. The ethical approval for the study protocol was officially granted by the Ethical Review Committee of the University (COA134/2564).

Measurements

The study instruments consisted of a questionnaire comprising demographic characteristics, work details, perceived adequate support from hospital and colleagues, and financial compensation. The questionnaire about perceived support used 5-point Likert scale, with 1 as strongly disagree and 5 as strongly agree.

Burnout syndrome was measured by the Thai version of the Maslach Burnout Inventory: General Survey (MBI-GS) which contains 16 items with three dimensions: emotional exhaustion (EE, 5 items; Cronbach’s alpha coefficient = 0.9), depersonalisation (DP, 5 items; Cronbach’s alpha coefficient = 0.7), and diminished personal accomplishment (PA, 6 items; Cronbach’s alpha coefficient = 0.7) [32, 33]. Subscales scores were considered as low, moderate or high level of burnout syndrome according to these cut-points; low EE ≤10, DP ≤ 5,PA ≥ 30; moderate EE = 11–15, DP = 6–10, PA = 25–29; high EE ≥ 16,DP ≥ 11, PA ≤ 24 [32].

Anxiety was measured by the Thai version of General Anxiety Disorder-7 (GAD-7) questionnaire. The scores were interpreted as followed: normal (0–4); mild (5–9); moderate (10–14); and severe (15–21). The cut-point for having anxiety was five yielding sensitivity and specificity, 89% and 82% respectively to detect generalised anxiety disorder [34].

Depression was measured with 2-step approach using the Thai Patient Health Questionnaire (PHQ-2 and Thai PHQ-9). Respondents who score ≥ 1 from PHQ-2 will be asked to answer PHQ-9. The scores were interpreted as follows: normal (0–6), mild (7–12), moderate (13–18), and severe (≥19). As Thai PHQ-9 score ≥ 7 is 95% sensitive and 55% specific for a diagnosis of major depression, the cut-point for having depression was seven [35, 36].

Post-traumatic stress disorder (PTSD) was measured by 3-questions, which we adapted from DSM-5 criteria [37]; presence of work-related trauma, presence of avoidance of relevant stimuli/hypervigilance or re-experiencing symptoms, and impaired function. All criteria must be met in order for participants to be identified as having PTSD.

At the end of the questionnaire, participants were addressed the confidentiality of the survey and asked the open-ended question; What factors will improve your mental health or reduce your stress? The participant’s narrative answer to this question will be analysed with qualitative methods.

Data analyses

Quantitative data analysis was performed using Stata version 14.0 (StataCorp, College Station, TX, USA). Descriptive statistics were used to explore ’HCWs’ characteristics and their mental health outcomes. The associations between the outcomes (burnout syndrome, anxiety, depression, and PTSD) and variables were assessed by the Chi-square test, ’ ’Fisher’s exact test, independent sample t-tests, or Mann–Whitney U tests. Binary logistic regression, followed by multiple logistic regression were used to calculate the odds ratios. Variables were included in the multivariable model if they have a p-value < 0.05 in univariable analysis.

As for qualitative data, answers to open-ended questions were analysed using content analysis. Two trained researchers independently coded the responses by means of inductive analysis, using the occurrence of themes and subthemes from texts. If inconsistency occurs, the researchers compared the analyses to reach a consensus before extracting statements that best represented each identified theme and subthemes.

Results

Of 3,218 hospital HCWs, 986 (31.5%) responded to the survey. The respondents included 623 nurses, 50 doctors, 173 allied health professionals, and 140 support staff. The majority of respondents across the positions mentioned above were female, and the mean age was 34.89±11.05. The median working hours per week (IQR) was 48 (40–56) hours. Interestingly, only 2.5% of respondents wished to receive counseling from the psychologist/psychiatrist. Other work characteristics and perceived support are presented in Table 1.

Table 1

Demographic, work characteristics, and perceived support (n = 986).

	N (%)
Sex
Male	107	(10.9)
Female	879	(89.1)
Age, year, Mean (SD)	34.89 (11.05)
Occupation
Nurse	623	(63.2)
Doctor	50	(5.1)
Allied health professional	173	(17.5)
Support staff; administrative, technicians, security, cleaners	140	(14.2)
Have a chronic medical condition	255	(25.9)
Have mental health illness	41	(4.2)
Current working unit
Non-Covid-19 related	358	(36.3)
OPD for patients with high-risk but unconfirmed COVID-19, parttime	252	(25.6)
OPD for patients with high-risk but unconfirmed COVID-19, fulltime	82	(8.3)
Non-ICU, with confirmed COVID-19 patients	91	(9.2)
ICU, with confirmed COVID-19 patients	82	(8.3)
Hospitel, with confirmed COVID-19 patients	121	(12.3)
Working hour (hours/week) median (IQR)	48	(40–56)
Have been transferred from other units (yes)	183	(18.6)
Intended not to go home (yes)	705	(71.5)
Perceived adequate support from hospital	3.51 ± 0.95
Perceived adequate support from collogues	4.04 ± 0.84
Perceived adequate financial compensation	2.70 ± 1.21
Wish to receive a counseling from a psychologist/psychiatrist
Yes	25	(2.5)
No	948	(96.1)
Uncertain	13	(1.3)

Data are presented as number (%), mean ± standard deviation or median (interquartile range).

Abbreviations: OPD, outpatient department; IPD, inpatient department; ICU, intensive care unit.

Prevalence of burnout and mental problems

Regarding the prevalence of burnout, 16.3%,16% and 53.5% of respondents had high level of EE, DP, and diminished PA, respectively. However, the figures of nurses, doctors and HCWs at COVID-19 inpatient units were higher as followed: Nurse (EE = 19.7%, DP = 17.8%), doctors (EE = 38.0%, DP = 44.0%), non-intensive care unit (EE = 27.5%, DP = 23.1%), intensive care unit (EE = 40.2%, DP = 31.7%). Additionally, overall, 16.2% had high level of burnout in 2 or more domains (Table 2).

Table 2

Prevalence of burnout and mental health problems.

Variables	N (%)
	All HCWs (n = 986)		Nurses (n = 623)	Doctors (n = 50)	IPD COVID (n = 91)	ICU COVID (n = 82)
Burnout syndrome
High EE	161	(16.3)	123 (19.7)	19 (38.0)	25 (27.5)	33 (40.2)
High DP	158	(16.0)	111 (17.8)	22 (44.0)	21 (23.1)	26 (31.7)
High PA	527	(53.5)	300 (48.2)	26 (52.0)	47 (51.6)	48 (58.5)
≥ 2 types of high burnout	160	(16.3)	117 (18.8)	11 (40.0)	24 (26.4)	34 (41.5)
Anxiety disorder (GAD-7)
Yes (≥5)	309	(31.3)	196 (31.5)	22 (44.0)	25 (27.5)	42 (51.1)
Depressive disorder
PHQ-9 (n = 312)
Yes (≥7)	136	(13.8)	87 (14.0)	16 (32.0)	11 (12.1)	18 (22.0)
Post-traumatic stress disorder
Yes	22	(2.2)	11 (1.8)	5 (10.0)	4 (4.4)	3 (3.66)

Abbreviations: EE, emotional exhaustion; DP, depersonalisation; PA, personal accomplishment; HCWs, healthcare workers; IPD, inpatient unit; ICU, intensive care unit.

With respect to anxiety, depression, and post-traumatic stress disorder, 33.4% of HCWs had anxiety, comprising 27.1%, 3.4%, 0.9% of mild, moderate and severe anxiety consecutively. 13.8% of HCWs had depression, comprising 10.7%, 2.1%, 1% of mild, moderate, severe depression consecutively. Finally, 2.2% of respondents were considered to have PTSD. Like burnout, these figures of nurses, doctors and HCWs working at COVID-19 inpatient units were higher (Table 2).

Associated factors of burnout

From univariate analysis, we found that sex and perceived support were associated with all domains of burnout. Age, occupation, working unit, working hour, and being transferred were associated with EE. Occupation, mental illness, working unit, working hour were associated with DP. Occupation, working unit were associated with PA.

From multivariable analysis, the male sex was associated with DP and PA (ORadj = 2.29 and 1.69). Nurses and doctors were risk factors of EE (ORadj = 3.04 and 4.29) and DP (ORadj = 2.74 and 4.61) Working at COVID-19 inpatient unit increased the risks of EE (non-intensive care unit; ORadj = 2.97, intensive care unit; ORadj = 3.00), while working at Hospitel reduced the risk (ORadj = 0.68). Mental illness and working hour were associated with DP. Perceived support from hospital reduced risks of EE and DP and perceived support from colleagues reduced the risk of PA (Table 3).

Table 3

Adjusted odds ratios from multivariable analysis of the associated factors of burnout among HCWs.

Factors	≥ 2 domains of high burnout			Emotional exhaustion			Depersonalisation			Personal achievement
	ORadj	95%CI	p-value	ORadj	95%CI	p-value	ORadj	95%CI	p-value	ORadj	95%CI	p-value
Sex
Male	2.10	(1.11–4.00)	0.023*	1.91	(1.00–3.66)	0.051	2.29	(1.25–4.20)	0.008*	1.69	(1.05–2.73)	0.032*
Female	1.00	Reference		1.00	Reference		1.00	Reference		1.00	Reference
Age, year, Mean (SD)	0.98	(0.96–1.00)	0.026*	0.97	(0.95–0.99)	0.001*
Occupation
Nurse	2.95	(1.32–6.56)	0.008*	3.04	(1.35–6.84)	0.007*	2.74	(1.34–5.62)	0.006*	0.70	(0.47–1.05)	0.086
Doctor	5.05	(1.94–13.1)	0.001*	4.29	(1.62–11.39)	0.003*	4.61	(1.91–11.11)	0.001*	0.56	(0.28–1.12)	0.099
Allied health professional	0.87	(0.33–2.31)	0.780	0.81	(0.30–2.20)	0.678	1.10	(0.45–2.64)	0.840	1.53	(0.94–2.48)	0.087
Support staff	1.00	Reference		1.00	Reference		1.00	Reference		1.00	Reference
Mental illness
No							1.00	Reference
Yes							2.70	(1.28–5.70)	0.009*
Current working unit
Non-Covid-19	1.00	Reference		1.00	Reference		1.00	Reference		1.00	Reference
Non-ICU COVID-19 IPD	2.79	(1.39–5.58)	0.004*	2.97	(1.50–5.87)	0.002*	1.71	(0.96–3.05)	0.071	0.88	(0.56–1.38)	0.576
ICU COVID-19 IPD	3.01	(1.60–5.63)	0.001*	3.00	(1.61–5.59)	0.001*	1.48	(0.84–2.62)	0.177	1.31	(0.80–2.12)	0.282
Hospitel	0.51	(0.17–1.5)	0.220	0.49	(0.17–1.43)	0.190	0.34	(0.13–0.88)	0.027*	1.32	(0.87–2.01)	0.185
Working hour (hours/week)
≤40	1.00	Reference		1.00	Reference		1.00	Reference
41–48	0.91	(0.52–1.59)	0.733	1.08	(0.62–1.88)	0.786	1.02	(0.59–1.76)	0.954
49–56	1.28	(0.75–2.18)	0.359	1.53	(0.91–2.59)	0.113	1.66	(0.99–2.77)	0.049*
>56	0.91	(0.56–1.49)	0.707	1.21	(0.75–1.96)	0.437	1.17	(0.73–1.88)	0.513
Transfer from other units
No	1.00	Reference		1.00	Reference
Yes	0.76	(0.46–1.27)	0.294	0.73	(0.44–1.21)	0.218
Support from hospital	0.56	(0.43–0.73)	<0.001*	0.68	(0.53–0.87)	0.003*	0.65	(0.51–0.83)	0.001*	0.86	(0.73–1.02)	0.087
Support from collogues	1.02	(0.80–1.31)	0.858	1.09	(0.85–1.39)	0.496	1.01	(0.80–1.29)	0.914	0.82	(0.68–0.99)	0.037*
Financial compensation	0.90	(0.74–1.1)	0.298	0.86	(0.71–1.04)	0.116	0.92	(0.76–1.11)	0.387

Abbreviations: ORadj, Adjusted Odds Ratio; CI, confident interval. Variable was included in multivariable model due to have p-value < 0.050 in univariable analysis.

Associated factors of mental problems

From univariate analysis, male sex and perceived support were associated with all mental health problems. Mental illness, working unit, working hour, and being transferred were associated with anxiety. Occupation, medical condition, mental illness, working unit, working hour were associated with depression. Medical conditions, mental illness, and working hour were associated with PTSD.

From multivariable analysis, male sex was associated with anxiety and PTSD (ORadj = 1.6 and,4.05). Having mental illness was associated with anxiety (ORadj = 2.89), depression (ORadj = 3.47), and PTSD (ORadj = 4.06). Working at the COVID-19 intensive care unit increased the risk of anxiety (ORadj = 2.07). Having 49–56 working hours/week increased the risk of PTSD (ORadj = 6.93). Perceived adequate hospital support reduced the risk of anxiety and depression. Occupation and chronic medical conditions were not associated with any mental problems (Table 4).

Table 4

Adjusted odds ratios from multivariable analysis of the associated factors of anxiety, depression, and PTSD among HCWs.

Factors	Anxiety			Depression			PTSD
	ORadj	95%CI	p-value	ORadj	95%CI	p-value	ORadj	95%CI	p-value
Sex
Male	1.65	(1.07–2.56)	0.025*	1.67	(0.90–3.10)	0.104	4.05	(1.10–14.95)	0.036*
Female	1.00	Reference		1.00	Reference		1.00	Reference
Occupation
Nurse				1.20	(0.64–2.26)	0.573	0.85	(0.19–3.71)	0.825
Doctor				1.92	(0.81–4.53)	0.138	1.64	(0.33–8.11)	0.545
Allied health professional				0.79	(0.36–1.74)	0.557	0.21	(0.02–2.09)	0.182
Support staff				1.00	Reference		1.00	Reference
Chronic medical condition
No				1.00	Reference		1.00	Reference
Yes				1.41	(0.92–2.15)	0.112	1.78	(0.66–4.80)	0.254
Mental illness
No	1.00	Reference		1.00	Reference		1.00	Reference
Yes	2.89	(1.50–5.57)	0.002*	3.47	(1.69–7.12)	0.001*	4.06	(1.09–15.12)	0.037*
Current working unit
Non-Covid-19	1.00	Reference		1.00	Reference
Non-ICU COVID-19 IPD	0.90	(0.50–1.63)	0.735	0.91	(0.45–1.84)	0.783
ICU COVID-19 IPD	2.07	(1.19–3.58)	0.010*	1.10	(0.58–2.09)	0.768
Hospitel	1.18	(0.64–2.17)	0.590	0.65	(0.31–1.37)	0.262
Working hour (hours/week)
≤40	1.00	Reference		1.00	Reference		1.00	Reference
41–48	1.41	(0.95–2.10)	0.089	1.53	(0.88–2.65)	0.135	4.30	(0.89–20.94)	0.071
49–56	1.25	(0.83–1.89)	0.282	1.43	(0.81–2.52)	0.212	6.93	(1.58–30.4)	0.010*
>56	0.93	(0.64–1.36)	0.711	1.58	(0.97–2.57)	0.067	3.58	(0.86–14.93)	0.080
Transfer from other units
No	1.00	Reference
Yes	1.29	(0.88–1.91)	0.194
Support from hospital	0.72	(0.59–0.87)	0.001*	0.67	(0.52–0.86)	0.002*	0.56	(0.29–1.08)	0.085
Support from collogues	0.88	(0.73–1.07)	0.206	1.06	(0.83–1.36)	0.636	0.58	(0.34–1.00)	0.051
Financial compensation	0.99	(0.86–1.14)	0.866	0.81	(0.67–0.98)	0.034	1.02	(0.58–1.81)	0.940

Abbreviations: ORadj, Adjusted Odds Ratio; CI, confident interval. Variable was included in multivariable model due to have p-value < 0.050 in univariable analysis.

Qualitative results

Of 986 respondents, 221 (25%) provided narrative responses to ’What factors will improve your mental health or reduce your stress?’. The answers related to work can be divided into 5 areas; 1) colleagues 2) financial compensation 3) workload 4) organisation management and policy 5) personal protective equipment (PPE).

1) Colleagues

43 out of 211 respondents (19.4%) said colleagues were a key factor in mental health conditions. The two main kinds of colleagues most desired by respondents were colleagues who can help each other and colleagues who are respectful and nonjudgmental.

“Having colleagues work together harmoniously, using humble words, honoring and respecting for each other and sharing responsibility. Good colleagues improve our mental health” (Nurse, 30 years old).

“I am lucky to have a close friend at work who can discuss and help each other in everything” (Nurse, 47 years old).

2) Financial compensation

Financial compensation was reported by 35 respondents (15.8%).

“It would be better if there was a compensation worth the risk according to the workload received. It is discouraged that the pay is not worth the hard work” (Nurse, 40 years old)

“Reasonable compensation! Now, it feels like working hard without being paid. Everyone should be paid for their hard work. Now I feel that I’m being taken advantage” (Doctor, 28 years old)

3) Workload

This issue was reported by 38 respondents (17.2%). The respondents wished for reduced workload, an increase in manpower or a circulation of healthcare workers to take care of COVID-19 patients, and more free time.

“Please reduce unrelated workload, for example, less paperwork” (Nurse, 43 years old)

“We need additional manpower. Hired more workers. Now, the patients are increasing while manpower remains unchanged” (Nurse, 49 years old)

“Having time to talk to someone could help ease the pressure and stress. I am still unsure if I should seek advice because I’m stressed but I am so busy working that I don’t think I have time for counseling” (Nurse, 48 years old)

4) Management and policy

This was reported by 27 respondents (12.0%). Management and policy-related issues included clarity in policy and communication and feedback pathway.

“Work or relocation should be notified early to allow time for preparation. The nature of the work descriptive should be clear” (Nurse, 46 years old)

“I wish executives meet and talk to encourage (workers) at the worksite more” (Doctor, 55 years old)

“I wish the executives visit the frontline personally. A policy, that empathies workers, notified clearly” (Doctor, 28 years old)

5) Personal Protective Equipment (PPE)

The issue was reported by 26 respondents (11.8%) who believed that having enough personal protective equipment would improve their mental health.

“Protective devices should be available fully, such as N95, hair cap, etc. Now they are scarce and insufficient, causing anxiety and insecurity while taking care of high-risk patients” (Nurse, 37 years old)

“Healthcare workers should be protected more. PPE should be sufficient. Workers should not be left to seek them themselves. With sufficient equipment and personnel, the anxiety can be reduced” (Nurse, 28 years old)

Discussion

To the best of our knowledge, this study is the first one to investigate the prevalence of burnout syndrome, depression, and post-traumatic stress disorder (PTSD) among Thai healthcare workers. From almost one thousand HCWs, the overall prevalence of burnout and PTSD was lower than that in the majority of studies but comparable to a study in India [12–15, 20]. The prevalence of anxiety and depression in our study is higher than in studies from Asia, which used the DASS-21 questionnaire as a measurement [10, 19–21]. However, the figures are smaller when compared to studies that used the GAD-7 and PHQ-9 questionnaires as we did [12, 27]. The smaller prevalence is suspected to result from the diversity of samples from various occupations and settings we included. Among those working at the intensive care unit, the prevalence of burnout was comparable to previous studies [16]. Also, emotional exhaustion and depersonalisation among nurses and doctors were also comparable to several studies [13]. However, it is noticeable that diminished personal accomplishment was high in all groups of research participants. This is likely because our study was conducted when the pandemic situation in Thailand began to be seriously exacerbated, leading to changes in the work routines of healthcare workers. As a consequence, Thai healthcare workers felt unprepared and incompetent.

Regarding risk factors of burnout, occupation and working units were the strongest associated factors of burnout. In line with previous studies, nurses, doctors, and those working with COVID-19 patients were at very high risk [13, 14]. From our study, those working at COVID-19 inpatients units both non-intensive care and intensive care unit (ICU) had approximately a threefold increase in risks of having emotional exhaustion. However, the risks did not increase for those working at a Hospitel. We did anticipate this result because patients admitted to a Hospitel were either asymptomatic or having mild severity of COVID-19. As a result, healthcare workers at a Hospitel would have lesser workload and exposure to patients.

Regarding risk factors for other mental health outcomes, we found from the multivariable analysis that the prominent risk factor was pre-existing mental illness. According to our study, underlying mental illnesses increased the risks of anxiety, depression, and PTSD, with ORadj 2.89, 3.47, and 4.06, respectively. This was congruence with studies from China [38, 39] and Italy [40, 41], and a multinational study from Asia [20]; however, the result is incongruent with a study from Lebanon [42]. As in previous studies, working in ICU increased the risk of anxiety [43, 44]. Nevertheless, we did not find a statistically significant association between occupation and anxiety, depression or PTSD [17]. We speculated that this was because mental illness and working unit played a more prominent role in our mixed-setting population.

Regarding gender and mental health, several studies highlighted gender differences in the psychological outcomes of HCWs [14, 45]. These findings had mixed results, but our result was consistent with studies from China [46, 47] that men had a greater chance of depersonalisation, lack of personal achievement, anxiety and PTSD. As the proportion of genders of HCWs in all occupations and settings were fairly similar in our study, we believe that male gender was an isolated risk factor in our sample.

Our study has emphasised the importance of support from hospital and colleagues, the issue of which was also addressed by previous studies [48, 49]. Perceived support from the hospital was negatively correlated with emotional exhaustion, depersonalisation, anxiety and depression, whereas perceived support from colleagues was negatively correlated with diminished personal accomplishment. Our qualitative analysis also pointed out modifiable associated factors; supportive and respectful colleagues, appropriate financial compensation, reduced workload, clarity of policy and communication channel, and adequate PPE. The findings suggest that organisational infectious preventive measures and PPE may reduce adverse psychological outcomes, which correlate with previous studies [50, 51]. Concerning financial support, while a study from Ghana found that tax-free salary reduced negative psychological impacts [52], direct studies on financial compensation’s impact on mental health are still lacking. Considering that the small proportion of healthcare workers did request counseling despite the high prevalence of mental problems in our study, actionable measures should be taken into account to prevent and reduce mental health problems among healthcare workers. However, among psychological treatments, cognitive behavioural therapy (CBT) is the most evidence-based treatment against psychiatric symptoms [53]. Additionally, internet-based CBT could be more proper than face-to-face CBT since it could prevent the spread of infection during the COVID-19 pandemic [54, 55].

Additionally, the result from the qualitative data revealed some healthcare workers believed that having supportive colleagues and effective hospital policy, including providing appropriate financial compensation, sufficient PPE, and empathy from executives, could benefit them to relieve psychological stress. These findings also support the quantitative results.

We acknowledge several limitations of this study. Firstly, due to the ’ ’study’s descriptive design at a single point of time, we cannot draw a conclusion about causal relationships and longitudinal outcomes. Secondly, according to convenience-based sampling, selective bias might occur, as HCWs with mental health problems might not want to participate in the study because they did not have enough time or energy to do so. This could result in an underestimation of problems. Thirdly, as research participants answered our open-ended question by typing a response instead of being interviewed, the information gathered could possibly be not in-depth. Fourthly, we did not gather some factors that potentially are confounders such as knowing someone who die of COVID-19. Also, some particular specialist doctors such as surgeons may experience more psychological problems than others [29]. Lastly, due to the diversity of medical services, our results could only be generalised to psychological outcomes of Thai HCWs in a tertiary-care hospital.

In conclusion, Thai HCWs also experienced negative mental health outcomes substantially. Prominent risk factors of burnout included nurse, doctors, and working at COVID-19 inpatient unit. Significant risk factors of anxiety, depression, and PTSD was pre-existing mental illness. HCWs in our study proposed measures to remediate their stress. These issues of mental health problems should be examined further, and some practical solutions to these problems should be put into action promptly for the improvement of Thai HCWs mental health.

(DTA)

Click here for additional data file.

31 Jan 2022

A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.

A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.

An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols.

We look forward to receiving your revised manuscript.

Kind regards,

Alison Wang

Academic Editor

PLOS ONE

Journal Requirements:

When submitting your revision, we need you to address these additional requirements.

1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at

https://journals.plos.org/plosone/s/file?id=wjVg/PLOSOne_formatting_sample_main_body.pdf and

https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf

2. Please provide additional details regarding participant consent. In the ethics statement in the Methods and online submission information, please ensure that you have specified (1) whether consent was informed and (2) what type you obtained (for instance, written or verbal, and if verbal, how it was documented and witnessed). If your study included minors, state whether you obtained consent from parents or guardians. If the need for consent was waived by the ethics committee, please include this information.

If you are reporting a retrospective study of medical records or archived samples, please ensure that you have discussed whether all data were fully anonymized before you accessed them and/or whether the IRB or ethics committee waived the requirement for informed consent. If patients provided informed written consent to have data from their medical records used in research, please include this information

3. In your Data Availability statement, you have not specified where the minimal data set underlying the results described in your manuscript can be found. PLOS defines a study's minimal data set as the underlying data used to reach the conclusions drawn in the manuscript and any additional data required to replicate the reported study findings in their entirety. All PLOS journals require that the minimal data set be made fully available. For more information about our data policy, please see http://journals.plos.org/plosone/s/data-availability.

"Upon re-submitting your revised manuscript, please upload your study’s minimal underlying data set as either Supporting Information files or to a stable, public repository and include the relevant URLs, DOIs, or accession numbers within your revised cover letter. For a list of acceptable repositories, please see http://journals.plos.org/plosone/s/data-availability#loc-recommended-repositories. Any potentially identifying patient information must be fully anonymized.

Important: If there are ethical or legal restrictions to sharing your data publicly, please explain these restrictions in detail. Please see our guidelines for more information on what we consider unacceptable restrictions to publicly sharing data: http://journals.plos.org/plosone/s/data-availability#loc-unacceptable-data-access-restrictions. Note that it is not acceptable for the authors to be the sole named individuals responsible for ensuring data access.

We will update your Data Availability statement to reflect the information you provide in your cover letter.

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

**********

4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

**********

5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: I have the following comments for the authors to address. I am happy to review this paper again.

1) Under the Introduction, the authors stated " Since the World Health Organization declaration on March 2020 [1]

the pandemic situation has been fluctuating, and the crisis has yet to be fully resolved". It is important to talk about the impact of pandemic on mental health based on the following landmark studies (but not limited to):

A systematic review of COVID-19 on mental health

Impact of COVID-19 pandemic on mental health in the general population: A systematic review [published online ahead of print, 2020 Aug 8]. J Affect Disord. 2020;277:55-64. doi:10.1016/j.jad.2020.08.001

The impact of COVID-19 on three continents:

A chain mediation model on COVID-19 symptoms and mental health outcomes in Americans, Asians and Europeans. Sci Rep 11, 6481 (2021). https://doi.org/10.1038/s41598-021-85943-7

The impact of COVID-19 on developing countries:

The impact of COVID-19 pandemic on physical and mental health of Asians: A study of seven middle-income countries in Asia. PLoS One. 2021 Feb 11;16(2):e0246824. doi: 10.1371/journal.pone.0246824. PMID: 33571297.

Government response during the pandemic:

Government response moderates the mental health impact of COVID-19: A systematic review and meta-analysis of depression outcomes across countries. J Affect Disord. 2021 May 27;290:364-377. doi: 10.1016/j.jad.2021.04.050. Epub ahead of print. PMID: 34052584.

Worst outcome of COVID infection due to depression

Association Between Mood Disorders and Risk of COVID-19 Infection, Hospitalization, and Death: A Systematic Review and Meta-analysis. JAMA Psychiatry. 2021 Jul 28. doi: 10.1001/jamapsychiatry.2021.1818. Epub ahead of print. PMID: 34319365.

2) Under the paragraph, "A number of studies also identified associated factors of negative mental health outcomes

63 among HCWs". Since Thailand belongs the Asia-Pacific, please comment on the research performed in this region based on the following landmark studies but not limited to the following studies Under the discussion, the authors should compare their findings with the findings from the following Asian countries:

Perception Toward Exposure Risk of COVID-19 Among Health Workers in Vietnam: Status and Correlated Factors. Front Public Health. 2021 May 25;9:589317. doi: 10.3389/fpubh.2021.589317. PMID: 34113595; PMCID: PMC8185209.

The impact of COVID-19 pandemic on global mental health: From the general public to healthcare workers. Ann Acad Med Singap. 2021 Mar;50(3):198-199. doi: 10.47102/annals-acadmedsg.202189. PMID: 33855314.

Asian-Pacific perspective on the psychological well-being of healthcare workers during the evolution of the COVID-19 pandemic. BJPsych Open. 2020;6(6):e116. Published 2020 Oct 8. doi:10.1192/bjo.2020.98

A multinational, multicentre study on the psychological outcomes and associated physical symptoms amongst healthcare workers during COVID-19 outbreak [published online ahead of print, 2020 Apr 21]. Brain Behav Immun. 2020;S0889-1591(20)30523-7. doi:10.1016/j.bbi.2020.04.049

Psychological Impact of the COVID-19 Pandemic on Health Care Workers in Singapore [published online ahead of print, 2020 Apr 6]. Ann Intern Med. 2020;M20-1083. doi:10.7326/M20-1083

Impacts of COVID-19 on the Life and Work of Healthcare Workers During the Nationwide Partial Lockdown in Vietnam. Front Psychol. 2021 Aug 19;12:563193. doi: 10.3389/fpsyg.2021.563193. PMID: 34489769; PMCID: PMC8417359.

3) Please discuss the impact on surgeons (beside phyisicians) during the pandemic based on the following study:

Psychological Health of Surgeons in a Time of COVID-19: A Global Survey [published online ahead of print, 2021 Jan 22]. Ann Surg. 2021;10.1097/SLA.0000000000004775. doi:10.1097/SLA.0000000000004775

4) Under discussion, please mention online psychological treatment e.g. Internet Cognitive Behavior Therapy (iCBT) to help healthcare workers based on the following studies under "actionable measures should be taken into account to prevent and reduce mental health problems among healthcare worker"

The most evidence-based treatment is cognitive behaviour therapy (CBT), especially Internet CBT that can prevent the spread of infection during the pandemic.

Use of Cognitive Behavior Therapy (CBT) to treat psychiatric symptoms during COVID-19:

Mental Health Strategies to Combat the Psychological Impact of COVID-19 Beyond Paranoia and Panic. Ann Acad Med Singapore. 2020;49(3):155‐160.

Cost-effectiveness of iCBT:

Moodle: The cost effective solution for internet cognitive behavioral therapy (I-CBT) interventions. Technol Health Care. 2017;25(1):163-165. doi: 10.3233/THC-161261. PMID: 27689560.

Internet CBT can treat psychiatric symptoms such as insomnia:

Efficacy of digital cognitive behavioural therapy for insomnia: a meta-analysis of randomised controlled trials. Sleep Med. 2020 Aug 26;75:315-325. doi: 10.1016/j.sleep.2020.08.020. Epub ahead of print. PMID: 32950013.

5) The authors found that "The issue was reported by 26 respondents (11.8%) who believed that having enough

228 personal protective equipment would improve their mental health." Under discussion, please discuss the findings of the following studies and how these studies support the above observation from psychoneuroimmunological and cultural perspectives:

Is Returning to Work during the COVID-19 Pandemic Stressful? A Study on Immediate Mental Health Status and Psychoneuroimmunity Prevention Measures of Chinese Workforce [published online ahead of print, 2020 Apr 23]. Brain Behav Immun. 2020;S0889-1591(20)30603-6. doi:10.1016/j.bbi.2020.04.055

The Association Between Physical and Mental Health and Face Mask Use During the COVID-19 Pandemic: A Comparison of Two Countries With Different Views and Practices. Front Psychiatry. 2020;11:569981. Published 2020 Sep 9. doi:10.3389/fpsyt.2020.569981

Reviewer #2: Thank you for the opportunity to review this mixed-methods study. This study aimed to explore the incidence and influence factors of burnout syndrome, anxiety, depression, and post-traumatic disorders (PTSD) among Thai healthcare workers during COVID-19 outbreak. The following comments and suggestions may helpful for the authors to improve the quality of this manuscript. The major problem of this study is design and reliability of mixed method study.

Abstract:

(1) Please use the full names when first time mention it, such as HCWs.

(2) Methods: that would be great if the authors could add more information about the study methods, including the study setting, participants, data analysis methods and other information if needed.

(3) Results: The results must include the overall findings of the mixed-methods study rather than each sub-study.

Introduction: This part needs more work to make it clear.

(1) It would be useful to mention the background and context of the Thai healthcare system, what are the differences of the healthcare workers who working in Thailand compared with healthcare workers from other countries?

“….healthcare systems are specific to their countries”, so please add more information about this and the background of this healthcare system must be provided as many studies from other countries had been published:

Thatrimontrichai, A., Weber, D. J., & Apisarnthanarak, A. (2021). Mental health among healthcare personnel during COVID-19 in Asia: A systematic review. Journal of the Formosan Medical Association.

Marvaldi, M., Mallet, J., Dubertret, C., Moro, M. R., & Guessoum, S. B. (2021). Anxiety, depression, trauma-related, and sleep disorders among healthcare workers duirng the COVID-19 pandemic: a systematic review and meta-analysis. Neuroscience & Biobehavioral Reviews.

Li, Yufei, Nathaniel Scherer, Lambert Felix, and Hannah Kuper. "Prevalence of depression, anxiety and post-traumatic stress disorder in health care workers during the COVID-19 pandemic: A systematic review and meta-analysis." PloS one 16, no. 3 (2021): e0246454.

(2) The authors should explain more healthcare workers’ mental health during COVID-19 outbreak, as the authors mentioned that “… psychological outcomes of healthcare workers (HCWs) during the pandemic have been extensively studied globally”.

(3) Some sentences need provide reference(s), for example, “…..there was a study in Thailand finding that 42.5% of healthcare workers had anxiety”, by the way, please mention this study recruited participants during the COVID19 or not. All the information needs to focus on the topic of this study.

Methods:

(1) All the study methods related to qualitative study/methods are missing, the authors need to describe the qualitative study and the whole mixed methods design clearly.

Methodological orientation and theory are lacking. What was the reason that you chose a mixed-methods approach. It should be supported using literature. The type of mixed methods used in your study should be described.

(2) Research/study procedure is also missing. What are trained data collectors?

(3) Please provide the psychometric properties of the questionnaires used in this study.

(4) Since both qualitative and quantitative data analysis has been used, the heading should be changed to 'data analysis' instead of 'Statistical analysis'.

Results and discussion:

(1) Data integration of quantitative and qualitative results is missing. The results section is unclear if the methods of this study is unclear. It is difficult to see how it is mixed with both quantitative and qualitative data.

(2) The quotes are very brief, and it is difficult for the reader to interpret the context of these quotes.

**********

6. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

6 Mar 2022

We thank the editor and the two reviewers for their comments on our manuscript. Below is

our response to each point raised by the academic editor and reviewers. We hope that we

satisfyingly addressed them and that the manuscript will be now suited for publication.

Academic editor:

1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at

We have already ensured our manuscript meet the requirements.

2. Please provide additional details regarding participant consent

We have added details about participant consent on lines 117-118.

Reviewer #1:

Q1: Under the Introduction, the authors stated " Since the World Health Organization declaration on March 2020 [1] the pandemic situation has been fluctuating, and the crisis has yet to be fully resolved". It is important to talk about the impact of pandemic on mental health based on the following landmark studies

We cited the data from the recommended articles in the introduction part.

1. A systematic review of COVID-19 on mental health Impact of COVID-19 pandemic on mental health in the general population: A systematic review. J Affect Disord. 2020;277:55-64. On line 56

2. The impact of COVID-19 on three continents: A chain mediation model on COVID-19 symptoms and mental health outcomes in Americans, Asians and Europeans. SciRep 11, 6481 (2021). On lines 56 and 60

3. The impact of COVID-19 pandemic on physical and mental health of Asians: A study of seven middle-income countries in Asia. PLoS One. 2021 Feb 11;16(2):e0246824. On line 56

4. Government response moderates the mental health impact of COVID-19: A systematic review and meta-analysis of depression outcomes across countries. J Affect Disord. 2021 May 27;290:364-377. On line 57

5. Association Between Mood Disorders and Risk of COVID-19 Infection, Hospitalization, and Death: A Systematic Review and Meta-analysis. JAMA Psychiatry. 2021 Jul 28.

On lines 58 and 61

Q2: Under the paragraph, "A number of studies also identified associated factors of negative mental health outcomes 63 among HCWs". Since Thailand belongs the Asia-Pacific, please comment on the research performed in this region based on the following landmark studies but not limited to the following studies Under the discussion, the authors should compare their findings with the findings from the following Asian countries:

We cited the data from the recommended articles in the introduction and discussion part.

1. Perception Toward Exposure Risk of COVID-19 Among Health Workers in Vietnam: Status and Correlated Factors. Front Public Health. 2021 May 25;9:589317. On lines 73

2. The impact of COVID-19 pandemic on global mental health: From the general public to healthcare workers. Ann AcadMed Singap. 2021 Mar;50(3):198-199. On lines 72, 94 and 241

3. Asian-Pacific perspective on the psychological well-being of healthcare workers during the evolution of the COVID-19pandemic. BJPsych Open. 2020;6(6):e116. Published 2020 Oct 8. On lines 79, 94 and 241

4. A multinational, multicentre study on the psychological outcomes and associated physical symptoms amongst healthcare workers during COVID-19 outbreak [published online ahead of print, 2020 Apr 21]. Brain Behav Immun. 2020;S0889-1591(20)30523-7. On lines 79, 94, 239, 241, and 261-262

5. Psychological Impact of the COVID-19 Pandemic on Health Care Workers in Singapore [published online ahead of print,2020 Apr 6]. Ann Intern Med. 2020;M20-1083. On lines 79, 94 and 241

6. Impacts of COVID-19 on the Life and Work of Healthcare Workers During the Nationwide Partial Lockdown in Vietnam.Front Psychol. 2021 Aug 19;12:563193. doi: 10.3389/fpsyg.2021.563193. On lines 79

Q3: Please discuss the impact on surgeons (beside phyisicians) during the pandemic based on the following study:

We cited the data from the recommended articles in the discussion part.

1. Psychological Health of Surgeons in a Time of COVID-19: A Global Survey [published online ahead of print, 2021 Jan22]. Ann Surg. 2021;10.1097/SLA. 0000000000004775. On lines 296-297

Q4: Under discussion, please mention online psychological treatment e.g. Internet Cognitive Behavior Therapy (iCBT) to help healthcare workers based on the following studies under "actionable measures should be taken into account to prevent and reduce mental health problems among healthcare worker"

We cited the data from the recommended articles in the discussion part on lines 285-287.

1. Use of Cognitive Behavior Therapy (CBT) to treat psychiatric symptoms during COVID-19: Mental Health Strategies to Combat the Psychological Impact of COVID-19 Beyond Paranoia and Panic. Ann Acad MedSingapore. 2020;49(3):155‐160.

2. Cost-effectiveness of iCBT: Moodle: The cost effective solution for internet cognitive

behavioral therapy (I-CBT) interventions. Technol Health Care.2017;25(1):163-165.

3. Internet CBT can treat psychiatric symptoms such as insomnia: Efficacy of digital cognitive behavioural therapy for insomnia: a meta-analysis of randomised controlled trials. Sleep Med.2020 Aug 26;75:315-325.

Q5: The authors found that "The issue was reported by 26 respondents (11.8%) who believed that having enough 228 personal protective equipment would improve their mental health." Under discussion, please discuss the findings of the following studies and how these studies support the above observation from psychoneuroimmunological and cultural perspectives:

We cited the data from the recommended articles in the discussion part on lines 279-280.

1. Is Returning to Work during the COVID-19 Pandemic Stressful? A Study on Immediate Mental Health Status and Psychoneuroimmunity Prevention Measures of Chinese Workforce [published online ahead of print, 2020 Apr 23]. Brain Behav Immun. 2020;S0889-1591(20)30603-6.

2. The Association Between Physical and Mental Health and Face Mask Use During the COVID-19 Pandemic: A Comparison of Two Countries With Different Views and Practices. Front Psychiatry. 2020;11:569981. Published 2020 Sep9.

Reviewer #2:

1. Abstract

(1) Please use the full names when first time mention it

We correct the full names following the reviewer’s comment on lines 25 and 44.

(2) Methods: that would be great if the authors could add more information about the study methods, including the study setting, participants, data analysis methods and other information if needed.

We added the recommended details of methods on lines 26-27, and 30-32.

2. Introduction

(1) It would be useful to mention the background and context of the Thai healthcare system, what are the differences ofthe healthcare workers who working in Thailand compared with healthcare workers from other countries?

We cited the data from the recommended articles in the introduction part.

1. Thatrimontrichai, A., Weber, D. J., & Apisarnthanarak, A. (2021). Mental health among healthcare personnel during COVID-19 in Asia: A systematic review. Journal of the Formosan Medical Association. On lines 68-70

2. Marvaldi, M., Mallet, J., Dubertret, C., Moro, M. R., & Guessoum, S. B. (2021). Anxiety, depression, trauma-related, and sleep disorders among healthcare workers during the COVID-19 pandemic: a systematic review and meta-analysis. Neuroscience & Biobehavioral Reviews. On lines 79

3. Li, Yufei, Nathaniel Scherer, Lambert Felix, and Hannah Kuper. "Prevalence of depression, anxiety and post-traumatic stress disorder in health care workers during the COVID-19 pandemic: A systematic review and meta-analysis." PloS one16, no. 3 (2021): e0246454. On lines 77

(2) The authors should explain more healthcare workers’ mental health during COVID-19 outbreak, as the authors mentioned that “… psychological outcomes of healthcare workers (HCWs) during the pandemic have been extensively studied globally”.

We discussed the more about this issue on lines 74-80.

(3) Some sentences need provide reference(s), for example, “…..there was a study in Thailand finding that 42.5% of healthcare workers had anxiety”, by the way, please mention this study recruited participants during the COVID19 or not. All the information needs to focus on the topic of this study.

We added detailed the more about this issue on line 96.

3. Methods

(1) All the study methods related to qualitative study/methods are missing, the authors need to describe the qualitative study and the whole mixed methods design clearly.

Methodological orientation and theory are lacking. What was the reason that you chose a mixed-methods approach. It should be supported using literature. The type of mixed methods used in your study should be described.

(2) Research/study procedure is also missing. What are trained data collectors?

(1) and (2); We added more details following the reviewer’s comment on lines 167-161.

(3) Please provide the psychometric properties of the questionnaires used in this study.

We added the psychometric properties of the questionnaires on lines 129-129, 134-134, and 139-140.

(4) Since both qualitative and quantitative data analysis has been used, the heading should be changed to 'data analysis ‘instead of 'Statistical analysis'

We changed the word “Statistical analysis” to “Data analysis” on line 149.

4. Results and Discussion

(1) Data integration of quantitative and qualitative results is missing. The results section is unclear if the methods of this study is unclear. It is difficult to see how it is mixed with both quantitative and qualitative data.

No data integration of quantitative and qualitative were executed.

We modified the manuscript to address the points made by the editor and the reviewers. We agreed with the comments in all accounts. We believe that the manuscript is now more readable, more informative, and its conclusions more useful to the public.

Submitted filename: Response to reviewers.docx

Click here for additional data file.

31 Mar 2022

A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.

A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.

An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols.

We look forward to receiving your revised manuscript.

Kind regards,

Alison Wang

Academic Editor

PLOS ONE

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: (No Response)

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: No

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: No

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: No

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: Thank you for the effort and amendments.

This is an important paper during the COVID-19 pandemic. I recommend publication.

Reviewer #2: Thanks for the opportunity to review this manuscript again. I think the authors did not revise the manuscript with my comments appropriately, for example, the mixed-methods design in this study is still unclear and there are many methodological issues in this manuscript.

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

1 Apr 2022

Academic editor:

1. Methods: please further elaborate the rationales for choosing mixed methods this study.

We choose a multiple method study design instead of mixed methods

2. Methods: For qualitative part, is there only one open-ended questions for qualitative data collection? any interview data? If only one open-ended question, content analysis might be quite more appropriate than the thematic analysis.

For the qualitative part, there are open-ended questions so, we use the content analysis instead of the thematic analysis method.

3. Methods/results: as you defined this study is a mixed methods study, but there is no any combination of the quantitative data and qualitative data. Combination is the key feature of mixed method study, otherwise it is much appropriate to define it as a multiple method study.

We define our study as a multiple method study, so there is no data integration of quantitative and qualitative were executed. In addition, we try to explain more about qualitative data in the method and discussion part.

Reviewer #2:

Thanks for the opportunity to review this manuscript again. I think the authors did not revise the manuscript with my comments appropriately, for example, the mixed-methods design in this study is still unclear and there are many methodological issues in this manuscript.

We define our study as a multiple method study using content analysis instead of thematic analysis because we asked only open-ended questions and there was no in-depth interview in this study. Furthermore, we try to explain more about qualitative data in the method and discussion part.

We modified the manuscript to address the points made by the editor and the reviewers. We agreed with the comments in all accounts. We believe that the manuscript is now more readable, more informative, and its conclusions more useful to the public.

Submitted filename: Response to reviewers_3.docx

Click here for additional data file.

6 May 2022

Mental health among healthcare workers during COVID-19 pandemic in Thailand

PONE-D-21-33387R2

Dear Dr. Kirdchok,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org.

If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

Kind regards,

Alison Wang

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

12 May 2022

PONE-D-21-33387R2

Mental health among healthcare workers during COVID-19 pandemic in Thailand

Dear Dr. Kirdchok:

I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department.

If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information please contact onepress@plos.org.

If we can help with anything else, please email us at plosone@plos.org.

Thank you for submitting your work to PLOS ONE and supporting open access.

Kind regards,

PLOS ONE Editorial Office Staff

on behalf of

Dr. Tao (Alison) Wang

Academic Editor

PLOS ONE