The Impact of Household Economic Deterioration Caused by the COVID-19 Pandemic and Socioeconomic Status on Suicidal Behaviors in Adolescents: A Cross-sectional Study Using 2020 Korea Youth Risk Behavior Web-based Survey Data.

OBJECTIVES: Economic hardship has a serious impact on adolescents' mental health. The financial impact of the coronavirus disease 2019 (COVID-19) pandemic was more severe for low-income families, and this also impacted adolescents. This study aimed to examine the associations of economic deterioration (ED) caused by the COVID-19 pandemic and low socioeconomic status (SES) with adolescents' suicidal behaviors. METHODS: This study analyzed data from the 2020 Korea Youth Risk Behavior Web-based Survey, which included 54 948 middle and high school students. Odds ratios (ORs) of suicidal ideation, suicidal planning, and suicide attempts related to ED and SES were calculated using multivariable logistic regression. We calculated relative excess risks due to interaction to assess additive interactions. RESULTS: The ORs for suicidal ideation, suicidal planning, and suicide attempts related to combined severe ED and low SES were 3.64 (95% confidence interval [CI], 3.13 to 4.23), 3.88 (95% CI, 3.09 to 4.88), and 4.27 (95% CI, 3.21 to 5.69), respectively. CONCLUSIONS: ED and low SES were significantly associated with suicidal behaviors in adolescents. Although no significant additive interaction was found, the ORs related to suicidal ideation, suicidal planning, and suicide attempts were highest among adolescents from low-income families with severe ED. Special attention is needed for this group, considering the increased impact of economic inequality due to the COVID-19 pandemic.

High Temperature and Its Association With Work-Related Injuries by Employment Status in South Korea, 2017-2018.

OBJECTIVE: This study aimed to determine the association between maximum daily temperature and work-related injuries according to employment status in South Korea. METHODS: Data on workers' compensation claims and daily maximum temperature between May 20 and September 10, 2017-2018, were collected and analyzed. The absolute temperature risk effect (ATR) was evaluated by comparing the risk effect at 2 temperatures (30°C vs 33°C) across all communities using 2-stage time-series analysis. RESULTS: The association between high temperatures and work-related injuries was statistically significant in the construction sector (ATR, 1.129; 95% confidence interval [CI], 1.010-1.261). In addition, the findings of this study also demonstrated a higher risk effect among nonpermanent workers (ATR, 1.109; 95% CI, 1.013-1.214) at 33°C versus 30°C when compared with permanent workers (ATR, 0.963; 95% CI, 0.891-1.041). CONCLUSIONS: This study found a significant association between high temperatures and work-related injuries among nonpermanent workers in South Korea.

A Health Information Quality Assessment Tool for Korean Online Newspaper Articles: Development Study.

BACKGROUND: Concern regarding the reliability and accuracy of the health-related information provided by online newspaper articles has increased. Numerous criteria and items have been proposed and published regarding the quality assessment of online information, but there is no standard quality assessment tool available for online newspapers. OBJECTIVE: This study aimed to develop the Health Information Quality Assessment Tool (HIQUAL) for online newspaper articles. METHODS: We reviewed previous health information quality assessment tools and related studies and accordingly developed and customized new criteria. The interrater agreement for the new assessment tool was assessed for 3 newspaper articles on different subjects (colorectal cancer, obesity genetic testing, and hypertension diagnostic criteria) using the Fleiss κ and Gwet agreement coefficient. To compare the quality scores generated by each pair of tools, convergent validity was measured using the Kendall τ ranked correlation. RESULTS: Overall, the HIQUAL for newspaper articles comprised 10 items across 5 domains: reliability, usefulness, understandability, sufficiency, and transparency. The interrater agreement for the article on colorectal cancer was in the moderate to substantial range (Fleiss κ=0.48, SE 0.11; Gwet agreement coefficient=0.74, SE 0.13), while for the article introducing obesity genetic testing it was in the substantial range, with values of 0.63 (SE 0.28) and 0.86 (SE 0.10) for the two measures, respectively. There was relatively low agreement for the article on hypertension diagnostic criteria at 0.20 (SE 0.10) and 0.75 (SE 0.13), respectively. Validity of the correlation assessed with the Kendall τ showed good correlation between tools (HIQUAL vs DISCERN=0.72, HIQUAL vs QUEST [Quality Evaluation Scoring Tool]=0.69). CONCLUSIONS: We developed a new assessment tool to evaluate the quality of health information in online newspaper articles, to help consumers discern accurate sources of health information. The HIQUAL can help increase the accuracy and quality of online health information in Korea.

Development and validation of prediction equations for the assessment of muscle or fat mass using anthropometric measurements, serum creatinine level, and lifestyle factors among Korean adults.

BACKGROUND/OBJECTIVES: The measurement of body composition, including muscle and fat mass, remains challenging in large epidemiological studies due to time constraint and cost when using accurate modalities. Therefore, this study aimed to develop and validate prediction equations according to sex to measure lean body mass (LBM), appendicular skeletal muscle mass (ASM), and body fat mass (BFM) using anthropometric measurement, serum creatinine level, and lifestyle factors as independent variables and dual-energy X-ray absorptiometry as the reference method. SUBJECTS/METHODS: A sample of the Korean general adult population (men: 7,599; women: 10,009) from the Korean National Health and Nutrition Examination Survey 2008-2011 was included in this study. The participants were divided into the derivation and validation groups via a random number generator (with a ratio of 70:30). The prediction equations were developed using a series of multivariable linear regressions and validated using the Bland-Altman plot and intraclass correlation coefficient (ICC). RESULTS: The initial and practical equations that included age, height, weight, and waist circumference had a different predictive ability for LBM (men: R2 = 0.85, standard error of estimate [SEE] = 2.7 kg; women: R2 = 0.78, SEE = 2.2 kg), ASM (men: R2 = 0.81, SEE = 1.6 kg; women: R2 = 0.71, SEE = 1.2 kg), and BFM (men: R2 = 0.74, SEE = 2.7 kg; women: R2 = 0.83, SEE = 2.2 kg) according to sex. Compared with the first prediction equation, the addition of other factors, including serum creatinine level, physical activity, smoking status, and alcohol use, resulted in an R2 that is higher by 0.01 and SEE that is lower by 0.1. CONCLUSIONS: All equations had low bias, moderate agreement based on the Bland-Altman plot, and high ICC, and this result showed that these equations can be further applied to other epidemiologic studies.

Poor People and Poor Health: Examining the Mediating Effect of Unmet Healthcare Needs in Korea.

OBJECTIVES: The purpose of this study was to estimate the mediating effect of subjective unmet healthcare needs on poor health. The mediating effect of unmet needs on health outcomes was estimated. METHODS: Cross-sectional research method was used to analyze Korea Health Panel data from 2011 to 2015, investigating the mediating effect for each annual dataset and lagged dependent variables. RESULTS: The magnitude of the effect of low income on poor health and the mediating effect of unmet needs were estimated using age, sex, education level, employment status, healthcare insurance status, disability, and chronic disease as control variables and selfrated health as the dependent variable. The mediating effect of unmet needs due to financial reasons was between 14.7% to 32.9% of the total marginal effect, and 7.2% to 18.7% in lagged model. CONCLUSIONS: The fixed-effect logit model demonstrated that the existence of unmet needs raised the likelihood of poor self-rated health. However, only a small proportion of the effects of low income on health was mediated by unmet needs, and the results varied annually. Further studies are necessary to search for ways to explain the varying results in the Korea Health Panel data, as well as to consider a time series analysis of the mediating effect. The results of this study present the clear implication that even though it is crucial to address the unmet needs, but it is not enough to tackle the income related health inequalities.

Stent Thrombosis With Drug-Eluting Stents and Bioresorbable Scaffolds: Evidence From a Network Meta-Analysis of 147 Trials.

OBJECTIVES: This study sought to perform a systematic review and network meta-analysis to compare the relative safety and efficacy of contemporary DES and BVS. BACKGROUND: To improve outcomes of patients undergoing percutaneous coronary revascularization, there have been advances in the design of drug-eluting stents (DES), including the development of drug-eluting bioresorbable vascular scaffolds (BVS). METHODS: Prospective, randomized, controlled trials comparing bare-metal stents (BMS), paclitaxel-eluting stents (PES), sirolimus-eluting stents (SES), Endeavor zotarolimus-eluting stents (E-ZES), cobalt-chromium (CoCr) everolimus-eluting stents (EES), platinum-chromium (PtCr)-EES, biodegradable polymer (BP)-EES, Resolute zotarolimus-eluting stents (R-ZES), BP biolimus-eluting stents (BP-BES), hybrid sirolimus-eluting stents (H [Orsiro]-SES), polymer-free sirolimus- and probucol-eluting stents, or BVS were searched in online databases. The primary endpoint was definite or probable stent thrombosis at 1 year. RESULTS: A total of 147 trials including 126,526 patients were analyzed in this study. All contemporary DES were superior to BMS and PES in terms of definite or probable stent thrombosis at 1 year. CoCr-EES, PtCr-EES, and H-SES were associated with significantly lower risk than BVS. CoCr-EES and H-SES were superior to SES and BP-BES. The risk of myocardial infarction was significantly lower with H-SES than with BVS. There were no significant differences regarding all-cause or cardiac mortality. Contemporary devices including BVS showed comparably low risks of repeat revascularization. CONCLUSIONS: Contemporary DES, including biocompatible DP-DES, BP-DES, and polymer-free DES, showed a low risk of definite or probable stent thrombosis at 1 year. BVS had an increased risk of device thrombosis compared with CoCr-EES, PtCr-EES, and H-SES. Data from extended follow-up are warranted to confirm the long-term safety of contemporary coronary devices.

Disparities in Children's Blood Lead and Mercury Levels According to Community and Individual Socioeconomic Positions.

We aimed to examine the associations between blood lead and mercury levels and individual and community level socioeconomic positions (SEPs) in school-aged children. A longitudinal cohort study was performed in 33 elementary schools in 10 cities in Korea. Among a total of 6094 children included at baseline, the final study population, 2281 children followed-up biennially, were analyzed. The geometric mean (GM) levels of blood lead were 1.73 µg/dL (range 0.02-9.26) and 1.56 µg/dL (range 0.02-6.83) for male and female children, respectively. The blood lead levels were significantly higher in males, children living in rural areas, and those with lower individual SEP. The GM levels of blood mercury were 2.07 µg/L (range 0.09-12.67) and 2.06 µg/L (range 0.03-11.74) for males and females, respectively. Increased blood mercury levels were significantly associated with urban areas, higher individual SEP, and more deprived communities. The risk of high blood lead level was significantly higher for the lower individual SEP (odds ratio (OR) 2.18, 95% confidence interval (CI) 1.36-3.50 in the lowest educational attainment of the father), with a significant dose-response relationship observed after adjusting for the community SEP. The association between high blood lead levels and lower individual SEP was much stronger in the more deprived communities (OR 2.88, 95% CI 1.27-6.53) than in the less deprived communities (OR 1.40, 95% CI 0.76-2.59), and showed a significant decreasing trend during the follow-up only in the less deprived communities. The risk of high blood mercury levels was higher in higher individual SEP (OR 0.64, 95% CI 0.40-1.03 in the lowest educational attainment of the father), with a significant dose-response relationship noted. Significant decreasing trends were observed during the follow-up both in the less and more deprived communities. From a public health point-of-view, community level intervention with different approaches for different metals is warranted to protect children from environmental exposure.

Association of cardiovascular health screening with mortality, clinical outcomes, and health care cost: a nationwide cohort study.

OBJECTIVE: To determine whether a cardiovascular disease (CVD) health screening program is associated with CVD-related health conditions, incidence of cardiovascular events, mortality, healthcare utilization, and costs. METHODS: Cohort study of a 3% random sample of all Korea National Health Insurance members 40years of age or older and free of CVD or CVD-related health conditions was conducted. A total 443,337 study participants were followed-up from January 1, 2005 through December 31, 2010. RESULTS: In primary analysis, the hazard ratios for CVD mortality, all-cause mortality, incident composite CVD events, myocardial infarction, cerebral infarction, and cerebral hemorrhage comparing participants who attended a screening exam during 2003-2004 compared to those who did not were 0.58 (95% CI: 0.53-0.63), 0.62 (95% CI: 0.60-0.64), 0.82 (95% CI: 0.78-0.85), 0.84 (95% CI: 0.75-0.93), 0.84 (95% CI: 0.79-0.89), and 0.73 (95% CI: 0.67-0.80), respectively. Screening attenders had higher rates of newly diagnosed hypertension, diabetes mellitus, and dyslipidemia, lower inpatient days of stay and cost, and lower outpatient cost compared to non-attenders. CONCLUSIONS: Participation in CVD health screening was associated with lower rates of CVD, all-cause mortality, and CVD events, higher detection of CVD-related health conditions, and lower healthcare utilization and costs.

The radiologic technologists' health study in South Korea: study design and baseline results.

PURPOSE: To describe the study design, methods, and baseline results of a prospective cohort of radiologic technologists which we have initiated in South Korea. METHODS: The cohort participants were enrolled through a self-administered questionnaire survey administered from April 2012 to May 2013. Survey data were linked with radiation dosimetry, a cancer registry, and health insurance data by personal identification numbers. A nationwide representative survey was also conducted using a stratified random sampling design with face-to-face interviews. RESULTS: A total of 12,387 radiologic technologists were enrolled, which accounted for approximately 63% of all diagnostic radiologic technologists working in South Korea. For nationwide survey, 585 workers were interviewed using the detailed questionnaire, and buccal cells were also collected by scraping the inside of the cheek. The majority of study subjects were under 50-year-old and male workers. The average annual effective dose of radiation declined both men (from 2.75 to 1.43 mSv) and women (from 1.34 to 0.95 mSv) over the period of 1996-2011. A total of 99 cancers (66 cancers in men and 33 in women) were reported from 1992 to 2010. The standardized incidence ratio of all cancer combined was significantly lower in men (SIR = 0.75, 95% CI 0.58-0.96) than general population, but the ratios for thyroid cancer were significantly higher than expected among both men and women. CONCLUSIONS: This cohort provides comprehensive information on work activities and health status of diagnostic radiologic technologists. In addition, the nationwide representative sample provides unique opportunities compared with previous radiologic technologist studies.

The incidence and prevalence of diabetes mellitus and related atherosclerotic complications in Korea: a National Health Insurance Database Study.

AIMS/INTRODUCTION: The incidence and prevalence of type 2 diabetes mellitus (T2DM) and related macrovascular complications in Korea were estimated using the Health Insurance Review and Assessment (HIRA) database from 2007-2011, which covers the claim data of 97.0% of the Korean population. MATERIALS AND METHODS: T2DM, coronary artery disease (CAD), cerebrovascular disease (CVD), and peripheral artery disease (PAD) were defined according to ICD-10 codes. We used the Healthcare Common Procedure Coding System codes provided by HIRA to identify associated procedures or surgeries. When calculating incidence, we excluded cases with preexisting T2DM within two years before the index year. A Poisson distribution was assumed when calculating 95% confidence intervals for prevalence and incidence rates. RESULTS: The prevalence of T2DM in Korean adults aged 20-89 years was 6.1-6.9% and the annual incidence rates of T2DM ranged from 9.5-9.8/1,000 person-year (PY) during the study period. The incidence rates of T2DM in men and women aged 20-49 years showed decreasing patterns from 2009 to 2011 (P<0.001); by contrast, the incidence in subjects aged 70-79 years showed increased patterns from 2009 to 2011 (P<0.001). The incidence rates of CAD and CVD in patients newly diagnosed with T2DM were 18.84/1,000 PY and 11.32/1,000 PY, respectively, in the year of diagnosis. Among newly diagnosed individuals with T2DM who were undergoing treatment for PAD, 14.6% underwent angioplasty for CAD during the same period. CONCLUSIONS: Our study measured the national incidences of T2DM, CAD, CVD, and PAD, which are of great concern for public health. We also confirmed the relatively higher risk of CAD and CVD newly detected T2DM patients compared to the general population in Korea.

Regional factors associated with participation in the national health screening program: a multilevel analysis using national data.

High participation rates are important for maximizing the effects of a health screening program. Previous studies have suggested that individual or regional characteristics have effects on health behaviors. In this study, we investigated the determinants of participation in the National Screening Program for Transitional Ages by simultaneously analyzing individual and area-level factors by multilevel analysis. A total of 1,081,216 subjects, aged 40 and 66 yr and nested in 254 areas, were included. There was a significant variation in participation rates across the areas even after adjusting for individual and area-level variables. Among the individual-level variables, increasing age, sex, higher income, and mild disability grade were associated with a higher participation rate. In urban areas, the 40-yr-old group had higher participation rates than the 66-yr-old group. Deprived areas had significantly high participation rates for both age groups. The number of screening centers per 1,000 inhabitants had no significant effect on participation in the screening program. In conclusion, regional characteristics are associated with participation rates independent of personal features and regional factors have differential effects with respect to age. A multi-dimensional approach is recommended to promote participation in health screening programs.

Quality of life assessment in male patients with androgenetic alopecia: result of a prospective, multicenter study.

BACKGROUND: Androgenetic alopecia (AGA) is a common hair loss disease with genetic predisposition among men and women, and it may commence at any age after puberty. It may significantly affect a variety of psychological and social aspects of one's life and the individual's overall quality of life (QoL). OBJECTIVE: This study aimed to investigate the QoL of AGA patients and discover the factors that can influence the QoL of AGA patients, including previous experience in non-medical hair care, reasons for hospital visits, age, duration, and the severity of AGA. METHODS: A total of 998 male patients with AGA were interviewed, using the Hair Specific Skindex-29 to evaluate the QoL of AGA patients. RESULTS: The results of the Hair Specific Skindex-29 on patients with AGA were as follows: symptom scale: 26.3±19.5, function scale: 24.0±20.1, emotion scale: 32.1±21.8, and global score: 27.3±19.1. According to this assessment, QoL was more damaged if the patient had severe alopecia, a longer duration of AGA, younger age, had received previous non-medical hair care, and visited the hospital for AGA treatment. CONCLUSION: This study showed that AGA could harmfully affect the patients' QoL. These findings indicate that dermatologists should address these QoL issues when treating patients with alopecia.

Prevalence of treated epilepsy in Korea based on national health insurance data.

The Korean national health security system covers the entire population and all medical facilities. We aimed to estimate epilepsy prevalence, anticonvulsant utilization pattern and the cost. We identified prevalent epilepsy patients by the prescription of anticonvulsants under the diagnostic codes suggesting seizure or epilepsy from 2007 Korean National Health Insurance databases. The information of demography, residential area, the kind of medical security service reflecting economic status, anticonvulsants, and the costs was extracted. The overall prevalence of treated epilepsy patients was 2.41/1,000, and higher for men than women. The age-specific prevalence was the lowest in those in their thirties and forties. Epilepsy was more prevalent among lower-income individuals receiving medical aid. The regional prevalence was the highest in Jeju Island and lowest in Ulsan city. New anticonvulsants were more frequently used than old anticonvulsants in the younger age group. The total annual cost of epilepsy or seizure reached 0.46% of total medical expenditure and 0.27% of total expenditure on health. This is the first nationwide epidemiological report issued on epilepsy in Korea. Epilepsy prevalence in Korea is comparable to those in developed countries. Economic status and geography affect the prevalence of epilepsy.

Contribution of income-related inequality and healthcare utilisation to survival in cancers of the lung, liver, stomach and colon.

OBJECTIVES: To examine differences in the survival rates of cancer patients according to socioeconomic status, focusing on the role of the degree of healthcare utilisation by the patient. METHODS: An observational follow-up study was done for 261 lung cancer, 259 liver cancer, 268 stomach cancer and 270 colon cancer patients, diagnosed during 1999-2002. Income status and healthcare utilisation were assessed with National Health Insurance (NHI) data; survival during 1999-2002 was identified by death certificate. HRs and 95% CI were derived from Cox proportional hazards regression. RESULTS AND CONCLUSIONS: The HRs for low income status are larger for colon cancer (2.37, 95% CI 1.17 to 4.80), followed by stomach (1.67, 95% CI 1.01 to 2.78), liver (1.57, 95% CI 1.03 to 2.39) and lung cancers (1.46, 95% CI 0.99 to 2.14). In the model including the variable of healthcare utilisation, colon and stomach cancers exhibited a lower HR in the moderate healthcare utilisation groups (0.40, 95% CI 0.21 to 0.76 in colon; 0.59, 95% CI 0.37 to 0.96 in stomach), whereas for liver cancer, the high utilisation group exhibited a higher hazard (1.72, 95% CI 1.07 to 2.75). A lower income status is independently related to a shorter survival time in cancer patients, especially in less fatal cancers. Healthcare utilisation independently affects the likelihood of survival from colon and stomach cancers, implying that a moderate degree of healthcare utilisation contributes to a longer survival time.

[Trend of socioeconomic inequality in participation in cervical cancer screening among Korean women].

OBJECTIVES: While cervical cancer is one of the leading cancers among women worldwide, there are a number of effective early detection tests available. However, the participation rates in cervical cancer screening among Korean women remain low. After the nationwide efforts in 1988 and thereafter to encourage participation in cervical cancer screening, few studies have investigated the effects of socioeconomic inequality on participation in cervical cancer screening. The purpose of this study was to investigate 1) the level of socioeconomic disparities in receiving cervical cancer screening by age group and 2) if there was an improvement in reducing these disparities between 1995 and 2001. METHODS: Using data from the Korean National Health Status, Health Behavior and Belief Survey in 1995, and the Korean National Health and Nutrition Examination Surveys from 1998 and 2001 (sample sizes of 2,297, 3,738, and 3,283), age-standardized participation rates were calculated according to education level, equivalized household income, and job status. Odds ratios and the relative inequality index (RII) were also calculated after controlling for age. RESULTS: Women with lower education levels were less likely to attend the screening test, and the disparities by education level were most pronounced among women aged 60 years and older. The RIIs among women 60 years and older were 3.64, 4.46, and 8.64 in 1995, 1998, and 2001, respectively. Higher rates of participation were reported among those in the highest income category, which was more notable among the middle aged women (40s and 50s). An inconsistent trend in the rate of participation in cervical cancer screening by occupational level was found. CONCLUSIONS: Indicators of socioeconomic position seem to have varying impacts on the inequalities in the rates of participation in cervical cancer screening according to age group. These results demonstrate the need for more aggressive and age-based interventions and policy programs to eliminate the remaining inequalities.

[Changes in smoking status among current male smokers and factors associated with smoking cessation success].

OBJECTIVES: This study (a) investigated the rate of smoking cessation sucess for current male smokers, and (b) identified the factors that are associated with the smoking cessation success. METHODS: Data were collected from four follow-up surveys of 700 current male smokers. The follow-up period was from December 2004 to June 2005. Success of smoking cessation was defined as "maintaining a smoking cessation status for six months". The demographic and socioeconomic factors included age, the household income level and, occupation. The smoking behavioral factors were composed of the amount of smoking, the duration of smoking, the age of initiating smoking, the willingness to quit, the frequency of trying to quit smoking and the smoker's attitude toward the anti-smoking policies. RESULTS: The proportion of quitters increased from 6.6% to 11.0% during the follow-up period. The majority of quitters answered that the increase of tobacco price acted as cue to achieve smoking cessation. The age-standardized experience and success rate of smoking cessation were 16.0% (95% C.I.=13.0% to, 19.0%) and 4.5% (95% C.I.=3.0% to, 6.0%), respectively. On the multivariate analysis, success for smoking cessation was associated with the willingness to quit smoking, low prior tobacco consumption, and agreement on the tobacco price increase. CONCLUSIONS: The results of this study suggest that the recent anti-smoking policies provided an opportunity to quit smoking. The results of this study can be used to establish evidence for further anti-smoking policies.

[Public perceptions of the risk of Asian dust storms in Seoul and its metropolitan area].

OBJECTIVES: In spite of the recent increased concern for Asian dust storms, there are few studies concerning how dangerous the general public recognizes these dust storms to be. This study examined the public's perceptions of the risk of the Asian dust storms and also the source of the information concerning the risk. METHODS: A telephone interview survey using a standardized questionnaire was done for the adults living in Seoul and its metropolitan area from May 15th, 2003 to May 16th, 2003. The contents of the questionnaire were the sociodemographic characteristics, the perceptions of risk to the Asian dust storms, and the coping strategy of the study participants. RESULTS: The study participants get their information on Asian dust storms mainly from TV newscasts and they have a good knowledge of them. They regard it as one of the most dangerous health risks, along with dioxin. They think that it is associated with allergic rhinitis, conjunctivitis and bronchial asthma, etc. Of the 500 study participants, 201(40.2%) persons suffered bodily discomforts during the Asian dust storm period. CONCLUSIONS: Although there are uncertainties about the health risks of Asian dust storms, the public thinks these dust storms are very dangerous to health in many ways. This negative perception will not disappear easily. To fill the gap of the public's perceptions of the risk and the objective evidence of its health effects, more studies about its health effects and the methods to reduce exposure are required.