OBJECTIVES: Firefighters are prone to suffer from psychological trauma and post-traumatic stress disorder (PTSD) in the workplace, and have a poor prognosis after PTSD. Reliable models for predicting PTSD allow for effective identification and intervention for patients with early PTSD. By collecting the psychological traits, psychological states and work situations of firefighters, this study aims to develop a machine learning algorithm with the aim of effectively and accurately identifying the onset of PTSD in firefighters, as well as detecting some important predictors of PTSD onset. METHODS: This study conducted a cross-sectional survey through convenient sampling of firefighters from 20 fire brigades in Changsha, which were evenly distributed across 6 districts and Changsha County, with a total of 628 firefighters. We used the synthetic minority oversampling technique (SMOTE) to process data sets and used grid search to finish the parameter tuning. The predictive capability of several commonly used machine learning models was compared by 5-fold cross-validation and using the area under the receiver operating characteristic curve (ROC-AUC), accuracy, precision, recall, and F1 score. RESULTS: The random forest model achieved good performance in predicting PTSD with an average AUC score at 0.790. The mean accuracy of the model was 90.1%, with an F1 score of 0.945. The three most important predictors were perseverance, forced thinking, and reflective deep thinking, with weights of 0.165, 0.158, and 0.152, respectively. The next most important predictors were employment time, psychological power, and optimism. CONCLUSIONS PTSD onset prediction model for Changsha firefighters constructed by random forest has strong predictive ability, and both psychological characteristics and work situation can be used as predictors of PTSD onset risk for firefighters. In the next step of the study, validation using other large datasets is needed to ensure that the predictive models can be used in clinical setting.
Humans ; Stress Disorders, Post-Traumatic/diagnosis* ; Firefighters/psychology* ; Cross-Sectional Studies ; Algorithms ; Machine Learning

PURPOSE: Firefighters are exposed to high levels of occupational risk factors, such as safety risks, chemical, ergonomic, and physical hazards that may jeopardize their lives. To overcome these hazards, firefighters must be physically, mentally, and personally fit to work. This study aimed to explore the criteria and factors affecting firefighters' resilience based on stakeholders' experiences. METHODS: This qualitative study was carried out using conventional content analysis. In total, 21 face-to-face interviews were conducted by firefighters who were experienced in the field. The interviews were carried out from July 2019 to January 2020. The data were collected using 3 unstructured interviews and then resumed by 18 semi-structured interviews. Data analysis was done using Graneheim method. RESULTS: The participants had more than 5 years of experience in the field of search and rescue. The extracted codes through data analysis were classified into 3 main categories (individual, organizational, and social factors), 9 sub-categories (mental, physical, occupational, managerial, colleagues-related, equipment-related, environmental, community-related, and family-related factors), as well as 19 sub-sub-categories and 570 codes. CONCLUSION Firefighters' personality, physical condition, behavior and psychological characteristics can affect their resilience along with organizational and management factors that play significant role in people's safety. Developing a tool for assessing resilience can help decision makers to have a real depict of firefighters' job qualifications.
Firefighters/psychology* ; Humans ; Qualitative Research

Firefighters have a high risk of developing cardiovascular and mental disorders due to their physical and chemical environments. However, in Korea, few studies have been conducted on environmental risk of firefighters. The Firefighter Research on the Enhancement of Safety and Health (FRESH) study aimed to discover the risk factors for cardiovascular disease and mental disorders among firefighters. Former and current firefighters were recruited from three university hospitals. A total of 1022 participants completed baseline health examinations from 2016 to 2017. All participants were scheduled for follow-ups every 2 years. Baseline health survey, laboratory testing of blood and urine samples, blood heavy metal concentration, urine polycyclic aromatic hydrocarbons (PAHs) metabolites, stress-related hormone test, natural killer cell activity, as well as physical and mental health examinations that focused on cardiovascular and mental disorders, were conducted. In addition, 3 Tesla (3T) brain magnetic resonance imaging (MRI) and neuropsychological tests were also performed to investigate structural and functional changes in the brains of 352 firefighters aged >40 years or new hires with less than 1 year of service.]]>
Brain ; Cardiovascular Diseases ; Cohort Studies ; Firefighters ; Follow-Up Studies ; Health Surveys ; Hospitals, University ; Humans ; Killer Cells, Natural ; Korea ; Magnetic Resonance Imaging ; Mental Disorders ; Mental Health ; Neuropsychological Tests ; Polycyclic Hydrocarbons, Aromatic ; Prospective Studies ; Republic of Korea ; Risk Factors

firefighters.MATERIALS AND METHODS: Data were obtained from the Firefighter Research: Enhancement of Safety & Health (FRESH) Study, which was designed to investigate the effects of job characteristics on mental and physical health among Korean firefighters. A total of 18101 firefighters were chosen from a nationwide sample. The Korean Emotional Labor Scale (K-ELS) was used to evaluate exposure to emotional labor, which consisted of five sub-factors: emotional demand and regulation, overload and conflict in customer service, emotional disharmony and hurt, organizational surveillance and monitoring, and lack of a supportive and protective system in the organization.RESULTS: Firefighters who were in the risk group were more likely to experience suicidal ideation than those in the normal group for each of the five sub-scales of emotional labor. The estimated mean values for suicidal ideation in the risk group were significantly higher than those in the normal group: 1.667 (95% CI: 1.344–2.069) for emotional demand and regulation, 1.590 (95% CI: 1.243–2.033) for overload and conflict in customer service, 2.409 (95% CI: 1.954–2.969) for emotional disharmony and hurt, 2.214 (95% CI: 1.832–2.676) for organizational surveillance and monitoring, and 1.665 (95% CI: 1.387–1.999) for lack of a supportive and protective system in the organization.CONCLUSION: These results suggest that experience and exposure to chronic and excessive emotional labor might play a crucial role in the development of suicidal ideation among firefighters.]]>
Firefighters ; Humans ; Suicidal Ideation

firefighters are exposed to hazardous environmental (chemical and physical) and working (shift work, psychological, and ergonomic factors) conditions that have reported or are suspected of adverse effects on reproductive health. However, no previous studies have reported on pregnancy, childbirth, and puerperium outcomes (PCPOs) in female firefighters.METHODS: The present study compared hospital admissions for PCPOs, based on 10th revision of the International Statistical Classification of Diseases and Related Health Problems (ICD-10) codes, among Korean female firefighters with those of the general Korean population. Standardized admission ratios (SARs) and their 95% confidence intervals (CIs) were calculated.RESULTS: The study population included 1,766 female firefighters. Total follow-up duration was 9,659 person-years. Compared to the general female population, the female firefighters' SARs were higher in all admissions for PCPOs (SAR, 1.92; 95% CI: 1.79–2.05); pregnancy and abortive outcomes (SAR, 1.56; 95% CI: 1.12–2.12); other maternal disorders predominantly related to pregnancy (SAR, 2.65; 95% CI: 1.99–3.46); maternal care related to the fetus, amniotic cavity, and possible delivery problems (SAR, 2.13; 95% CI: 1.74–2.57); labor and delivery complications (SAR, 1.55; 95% CI: 1.15–2.06); delivery (SAR, 1.94; 95% CI: 1.80–2.08); and complications predominantly related to puerperium (SAR, 4.68; 95% CI: 2.02–9.23).CONCLUSION: The results of this study showed high SARs in all and specific subcategories of PCPOs in female firefighters.]]>
Female ; Fetus ; Firefighters ; Follow-Up Studies ; Humans ; International Classification of Diseases ; Korea ; Parturition ; Postpartum Period ; Pregnancy ; Reproductive Health

Firefighters are exposed to many dangerous working conditions. Many studies have identified the risk of disease for firefighters, but only a few studies have addressed the medical expenses of firefighters, which represents a concrete scale of disease. Our purpose in this study was to determine the medical expenditures of firefighters to assess the overall scale of disease in Korea. We focused on cancer, mental disorders, cardio-cerebrovascular disease, and musculoskeletal disease, the prevalence of which was expected to be high in firefighters.METHODS: This study utilized National Health Insurance Service data. We targeted firefighters, police officers, and government officials. We classified disease based on the 10th revision of the International Statistical Classification of Diseases and Related Health Problems codes. We compared prevalence by the age-standardized prevalence rate, considering standard distribution of the population. Medical expenditure of disease was defined as outpatient fees, hospitalization fees, and drug costs. Total medical expenditures were calculated by the sum of those 3 categories.RESULTS: The age-standardized prevalence of cancer, mental disorders, and cardiovascular disease in firefighters was slightly higher than or similar to that of government officials and police officers (no significant difference). However, medical expenditures for stomach cancer, mental disorders, and most cardio-cerebrovascular diseases were higher in firefighters than in others. In particular, firefighters spent 12 times more money for ischemic heart disease than did government officials. Of musculoskeletal diseases, lumbar disc disorder had the highest expenditures among firefighters.CONCLUSIONS: The age-standardized prevalence of most of diseases of firefighters was not as high as in the other groups, but the medical expenses of firefighters were much higher than those of government officials and police officers.]]>
Cardiovascular Diseases ; Drug Costs ; Fees and Charges ; Firefighters ; Health Expenditures ; Hospitalization ; Humans ; International Classification of Diseases ; Korea ; Mental Disorders ; Musculoskeletal Diseases ; Myocardial Ischemia ; National Health Programs ; Occupational Groups ; Outpatients ; Police ; Prevalence ; Stomach Neoplasms

firefighters, smoking management is important because they are exposed to various harmful substances in their occupational environment. Accurate surveys of smoking status are essential to control tobacco use. The main disadvantage of self-report questionnaires, which are commonly used for investigating smoking status, is the possibility that the subjects' response are invalid. If the validity of firefighters' answers on smoking questionnaires is not adequate, different methods will be needed for investigating smoking status in firefighters.METHODS: This study was conducted on 445 male firefighters from 9 fire stations in Daegu (the city in South Korea) who visited a medical institution for medical checkup in 2016. The urine cotinine test strip (DCT-102; CLIAwaived Inc., cut-off value = 200 ng/mL) was used to classify the actual smoking status and to assess the validity of self-reported smoking status on questionnaires. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the smoking questionnaires were analyzed. Subjects testing positive in the urine cotinine test (assumed the actual current smokers) were selected. The frequency at which actual current smokers were misclassified as current non-smokers by the questionnaire was calculated. Subjects' characteristics were analyzed for possible association with any discrepancy between self-reported smoking status and urine cotinine test results.RESULTS: The smoking rates among firefighters surveyed using the smoking questionnaire and the urine cotinine test were 22.47% and 51.24%, respectively. Of the all subjects, 29.66% (n = 132) were misclassified. The sensitivity of the smoking questionnaire was 42.98%, the specificity was 99.08%, the PPV was 98.00%, and the NPV was 62.32%. In the 228 subjects classified as current actual smokers by the urine cotinine test, 57.02% (n = 130) were misclassified on the questionnaire. The misclassification rate increased with age. The degree of misclassification also increased when subjects had a history of disease.CONCLUSIONS: In present study, the validity of the smoking questionnaire for firefighters was not suitable for investigating smoking status due to low sensitivity. To increase the validity of smoking status monitoring in firefighters, consideration of the various factors like survey environment, subjects' characteristics, and occupational factors is needed.]]>
Cotinine ; Daegu ; Firefighters ; Fires ; Humans ; Male ; Sensitivity and Specificity ; Smoke ; Smoking ; Tobacco Use

PURPOSE: The purpose of this study was to identify the relationships among occupational identity, social support, posttraumatic growth, and health-related quality of life regarding firefighters.METHODS: The study was conducted with 149 firefighters working at two fire stations in South Gyeongsang Province. Data were collected between August and September 2018. There were four research instruments in the structured survey, including the occupational identity scale, social support scale, Korea Posttraumatic Growth Inventory and World Health Organization Quality of Life Assessment Instrument.RESULTS: As a result, the quality of life of firefighters was positively correlated with social support, occupational identity, and posttraumatic growth. The factors associated with the quality of life of firefighters were social support (β=.36, p < .001), and occupational identity (β=.31, p < .001). The total explanatory power of these variables was 53.1%.CONCLUSION: To improve the health-related quality of life of firefighters based on the results of this study, it is necessary to develop support programs to strengthen social support and occupational identity.
Firefighters ; Fires ; Humans ; Korea ; Occupations ; Quality of Life ; Social Identification ; World Health Organization

BACKGROUND: Emergency workers such as firefighters are cataloged within the most demanding and injurious professions globally. Considering the health and safety implications in firefighting, a lot of research needs to be conducted to examine how firefighters' task characteristics and their work demand influence the development of work-related musculoskeletal disorders (WMSDs). This study therefore examines how the task characteristics of firefighters moderates the relationship between their work demand and the development of WMSDs. METHODS: Convenient sampling was employed to select 320 firefighters in the Greater Accra region of Ghana. Data were analyzed using descriptive statistics, correlation, and regression. RESULTS: The findings revealed that work demand and task characteristics have significant positive effects on WMSDs. Again, the task characteristics of firefighters moderates the relationship between their work demand and WMSDs. CONCLUSION: Since the study shows that task characteristics influences the relationship between work demand and WMSDs, it is vital for managers to constantly modify the nature of tasks performed by and work demand of emergency workers to minimize the development of WMSDs and other industrial health complications.
Emergencies ; Firefighters ; Ghana ; Humans ; Occupational Health

BACKGROUND: This cross-sectional study assessed the sleep quality using the ActiGraph and investigated the relationship between the parameters of sleep assessment and the type of shift work in Korean firefighters. METHODS: The participants were 359 firefighters: 65 day workers (control group) and 294 shift workers (shift work group: 77 firefighters with 3-day shift, 72 firefighters with 6-day shift, 65 firefighters with 9-day shift, and 80 firefighters with 21-day shift). Sleep assessments were performed using the ActiGraph (wGT3X-BT) for 24 hours during day shift (control and shift work group) and night shift and rest day (shift work group). The participants recorded bed time and sleep hours during the measurement period. RESULTS: Sleep efficiency, total sleep time, and percentage of wake after sleep onset during night work were lower in the shift work group than control group (p < 0.05). Sleep efficiency decreased in night shift and increased in rest day, whereas wake after sleep onset increased in night shift and decreased in rest day (p < 0.05). Among shift work groups, sleep efficiency of 6-day shift was higher in day shift, and sleep efficiency of 21-day shift was lower in night shift than other shift groups (p < 0.05). CONCLUSION: We found that the sleep quality in night shift of the shift work group was poorer than the control group. As to the type of shift work, sleep quality was good in 6-day shift and poor in 21-day shift. Thus, fast rotating shift such as 6-day shift may be recommended to improve the sleep quality of the firefighters.
Cross-Sectional Studies ; Firefighters ; Humans