Working hours and the regulations in Korea.

South Korea has the highest policy priority for working hour regulations because it has longer annual working hours than other Organization for Economic Development Co-operation and Development countries and has fewer holidays. According to the results of the Working Conditions Surveys between 2006 and 2020, in 2020, 6% of wage earners worked for > 52 hours weekly. The percentage of workers exceeding 52 hours weekly has decreased over time; however, disparities exist based on age, industry, occupation, company type, and company size, particularly in service-, arts-, and culture-related occupations and workplaces with fewer than 5 employees. South Korea's working hours system is greatly influenced by the 52-hour weekly maximum; sometimes, a maximum of 64-69 hours, including overtime, is theoretically possible. To ensure healthy working hours, it is important to actively protect workers who fall through the cracks, such as those in businesses with fewer than 5 employees.

Association between long working hours and unmet dental needs in wage workers.

BACKGROUND: Many previous studies on the reasons behind unmet dental needs focus on economic issues. However, in this research, we aimed to investigate the relationship between long working hours and unmet dental needs while considering the influence of occupational factors in wage workers. METHODS: This study used data from the Korea National Health and Nutrition Examination Survey (2012-2018) and analyzed a sample of 12,104 wage workers. Unmet dental needs were defined as cases in which individuals did not receive dental care, despite their need for examination or treatment, within the last year. Long working hours were defined as exceeding 52 h per week, based on the standard working hours stipulated by the Labor Standards Act. A binomial model was applied to calculate the prevalence ratio through multivariate logistic regression analysis. RESULTS: The prevalence of unmet dental needs was observed in 3,948 cases (32.5%), among which 1,478 attributed their presence to lack of time. The prevalence of unmet dental needs showed an inverse relationship with the education level and household income. The wage workers who worked long hours had the highest prevalence of unmet dental needs. Long working hours were found to be 1.18 times (95% CI 1.07-1.29) more likely to result in unmet dental care compared to working less than 40 h. The relationship between long working hours and unmet dental needs were statistically significant only in men (PR 1.24, 95% CI 1.07-1.43). However, the relationship between long working hours and unmet dental needs owing to time were in both men and women (men: PR 1.59, 95% CI 1.20-2.11, women: PR 1.90, 95% CI 1.48-2.43). CONCLUSIONS: This study confirmed that long working hours and unmet dental needs are related when occupational factors are taken into consideration, despite the absence of oral health indicators. Using this study as a reference, further research is necessary to identify the underlying causes of unmet dental care and to improve access to dental services in the future.

Development of Korean CARcinogen EXposure: Assessment of the Exposure Intensity of Carcinogens by Industry.

Background: Occupational cancer is a global health issue. The Korean CARcinogen EXposure (K-CAREX), a database of CARcinogen EXposure, was developed for the Korean labor force to estimate the number of workers exposed to carcinogens by industry. The present study aimed to estimate the intensity of exposure to carcinogens by industry, in order to supply complementary information about CARcinogen EXposure intensity to the K-CAREX. Methods: We used nationwide workplace monitoring data from 2014 to 2016 and selected target carcinogens based on the K-CAREX list. We computed the 95th percentile levels of measurements for each industry by carcinogens. Based on the 95th percentile level relative to the occupational exposure limit, we classified the CARcinogen EXposure intensity into five exposure ratings (1-5) for each industry. Results: The exposure ratings were estimated for 21 carcinogenic agents in each of the 228 minor industry groups. For example, 3,058 samples were measured for benzene in the manufacturing industry of basic chemicals. This industry was assigned a benzene exposure rating of 3. Conclusions: We evaluated the CARcinogen EXposure ratings across industries in Korean workers. The results will provide information on the exposure intensity to carcinogens for integration into the K-CAREX. Furthermore, it will aid in prioritizing control efforts and identifying industries of concern.

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.

Comparison of Work-Related Stress in Cluster of Workers' Suicides in Korea: Analysis of Industrial Accident Compensation Insurance, 2010-2017.

BACKGROUND: There is limited research on the heterogeneity of worker suicides. We compared differences in workers' suicides by clustering suicide deaths. METHODS: From 2010 to 2017, 353 suicide deaths were claimed in the Industrial Accident Compensation Insurance; variables were coded using a standardized methodology. A two-step cluster analysis classified the clusters based on demographic and employment conditions. Details of the suicide, clinical variables, personal stresses, and work-related stresses were compared using the chi-square test and one-way analysis of variance. RESULTS: We identified five clusters and they differed particularly in work-related stress. "Responsibility-burdened type" experienced excessive responsibility as managers; "role-changed type" experienced a sudden and unpredictable role change as clerks or sales workers; "risk-exposed type" experienced physical risk factors at work (working alone, outdoors, and in shifts) as machine operating and assembling workers, or craft and related trades workers; "job-insecurity type" experienced unstable employment (irregular, nonpermanent) as elementary or service workers; "workplace-violence type" was mainly unmarried women who lived alone, and experienced interpersonal conflict and violence as professionals and related workers. There were no differences between clusters in clinical variables (except problem drinking) and personal stresses. CONCLUSION: Interventions to alleviate work-related stress in worker clusters are needed to prevent suicide in workers.

Assessment of sunlight exposure across industries and occupations using blood vitamin D as a biomarker.

OBJECTIVE: Exposure to ultraviolet (UV) radiation from sunlight induces the production of essential vitamin D, whereas overexposure to sunlight leads to skin cancer. Sunlight exposure has been measured using questionnaires, dosimeters, and vitamin D levels. Several studies have measured vitamin D in the working population; however, these studies were limited to certain occupations such as farmers and construction workers. In the present study, we evaluated sunlight exposure using blood vitamin D as an exposure surrogate across industries and occupations. METHODS: The Korea National Health and Nutrition Examination Survey (KNHANES) is a nationwide study representing the Korean population. We analyzed data from KNHANES between 2008 and 2009. We examined the association between vitamin D levels and pertinent personal, seasonal, residential, and occupational factors. Furthermore, we developed a multiple regression model with factors other than occupational factors (industry and occupation) and obtained residual values. We computed the third quartile (Q3) of the residuals and then calculated the fractions exceeding the Q3 level for each combination of industry and occupation. RESULTS: Age, sex, body mass index, year, season, latitude, living area, living in an apartment, industry, and occupation were significantly associated with vitamin D levels. Based on the exceeding fraction, the armed forces showed the highest exceeding fraction level of 0.71. CONCLUSIONS: Our results present the high exposure groups to sunlight across industries and occupations. Our results may provide a source for prioritizing occupational groups with a high risk of adverse health effects from sunlight exposure.

The effect of first- and third-generation prophylactic antibiotics on hospitalization and medical expenditures for cardiac surgery.

BACKGROUND: This study investigated the efficacy of first-generation (cefazolin) and third-generation (ceftizoxime) prophylactic antibiotics in patients undergoing cardiac surgery and the incidence of surgical site infections, hospitalizations, and medical costs. METHODS: All adult patients (≥ 20 years) undergoing cardiac surgery at one hospital from January 01, 2009, to December 31, 2016, were included in this study. A single prophylactic antibiotic was administered at a dose of 1 g within one hour of the surgical incision and for three days after surgery at eight-hour intervals. After propensity score matching, 194 patients in each antibiotic prophylaxis group (first-generation vs third-generation) were analyzed. Among the 388 patients, the incidence of surgical site infections was compared according to the type of prophylactic antibiotic, and risk factors were evaluated by chi-squared tests followed by multivariate logistic regression analysis. RESULTS: The incidence of deep surgical site infections was significantly lower in the first-generation group (5.7%) than in the third-generation group (16.5%). The pathogens isolated from the surgical infection sites were similarly distributed in both groups. However, the prevalence of highly infectious gram-positive bacteria was more than that of gram-negative bacteria (67% vs 23%). The preoperative hospitalization duration, mean operation time, and ventilator use time were similar in both groups, but the postoperative hospitalization duration was significantly shorter in the first-generation group (25.5 days) than in the third-generation group (29.8 days). In addition, the medical costs were lower in the first-generation group (20,594 USD) than in the third-generation group (26,488 USD). CONCLUSION: In conclusion, the first-generation prophylactic antibiotic was better than the third-generation in reducing surgical site infection rates, hospitalization length, and medical expenditures.

Ophthalmic complications in retinopathy of prematurity in the first decade of life in Korea using the national health insurance database.

The aim of this study is to investigate the epidemiology of ophthalmic complications of retinopathy of prematurity (ROP) after preterm birth using population-based database in South Korea. Using the National Health Insurance database, ophthalmic complications among premature infants born in 2007-2008 during their 10-year follow-up period were identified. Annual cumulative incidence rate and period prevalence of complications at each age were analyzed among those with ROP and those who underwent treatment for ROP (tROP). The hazard ratios (HRs) according to the presence of ROP and treatment for ROP were also analyzed. We identified 18,256 premature infants, 6995 of whom had ROP. The prevalence at 10th year for overall ophthalmic complications was 11.1% and 35.9% among ROP and tROP, respectively. Strabismus, amblyopia, and glaucoma were the three most common complications. The presence of ROP was associated with higher risk of complications (HR 1.53, 95%CI 1.44-1.61) among premature infants, and the presence of treatment for ROP was associated with higher risk of complications (HR 4.31, 95%CI 3.74-4.98) among ROP cases. This study reports the nationwide epidemiologic data on ophthalmic complications of ROP during the first decade of life, which will help advance our understandings and establish national strategies in managing ROP.

Pregnancy loss and Income in the Republic of Korea using National Health Insurance Service Data, 2008-2014.

BACKGROUND: Although unintentional pregnancy loss is common, national representative statistics are lacking in high-income East Asian countries undergoing rapid demographic changes. It is necessary to confirm the income inequality of pregnancy loss even in universal national health insurance. METHOD: Using National Health Insurance Service data between 2008 and 2014, the annual prevalence of pregnancy loss was enumerated, and differences in pregnancy loss according to age and income levels were assessed by multivariable Poisson regression. Joint-point regression was used to examine the trend of pregnancy loss. RESULT: On average, there was a 15.0% annual pregnancy loss among 3,941,020 pregnancy cases from 2008 to 2014. Pregnancy loss inequality increased stepwise with income levels except for the highest income group. After adjusting for income levels, the annual percent change of age-standardized prevalence significantly increased by 2.6% every year since 2011. CONCLUSION: Even in high-income countries with universal national health insurance, income inequality in pregnancy loss is observed. Further appraisal is needed to explain the increasing trend of pregnancy loss between 2011 and 2014 even after adjusting income.

Emotional Demand and Mental Health in Korean Employees.

BACKGROUND: Emotional demand (ED) at work is related to mental health in the general workforce, not just emotional workers. We investigated the relationships between ED and mental health outcomes, including distress, depressive symptoms (DS), experience of depression (DE), and suicidal ideation (SI) on the entire general workforce using nationally representative data. METHODS: 5787 full-time employees were analyzed using cross-sectional design with the fourth Korean National Health and Nutrition Examination Survey (K-NHANES IV). Work-related psychosocial factors and mental health status were measured through face-to-face interviews. Multi-stage and stratified survey designs were considered in the analysis, and the mental health effects of ED were analyzed using multivariable logistic analysis. The Cochran-Armitage trend test was conducted to investigate increases in the relationship between the severity of ED and mental health outcomes. RESULTS: The subjects comprised 3089 men and 2698 women. ED was reported by 36.7% of men and 39.3% of women. The estimated prevalence of distress was 27.5% in men and 34.6% in women. Adjusted odds ratios (ORs) of ED for distress were 2.62 (95% confidence interval (CI) = 2.10-3.28) for men and 2.57 (95% CI = 1.92-3.45) for women. DS was significantly related to ED (men: OR = 1.72, 95% CI = 1.18-2.50; women: OR = 1.91, 95% CI = 1.33-2.74). ED was also significant psychosocial risk factor for DE (men: OR = 1.88, 95% CI = 1.07-3.29; women: OR = 1.77, 95% CI = 1.15-2.75) and SI (men: OR = 1.64, 95% CI = 1.11-2.41; women: OR = 2.31, 95% CI = 1.63-3.28). CONCLUSIONS: ED was a risk factor for distress, DS, DE, and SI in the general workforce. Legal and social safety networks should be constructed for workers whose emotions may be hidden at work, as well as workers in emotion-related fields.

Occupation, work-related stress, and personal characteristics among suicide deaths with occupation-related compensation claims in Korea.

OBJECTIVES: This study compared differences in age-standardized suicide mortality rates, personal characteristics (demographics, employment conditions, and details of suicide), and work-related stress by gender and occupation among workers who had committed suicide in Korea. METHODS: Data comprised 413 suicide death claims lodged with the Industrial Accident Compensation Insurance (IACI) from 2010 to 2018, which were coded. We calculated age-standardized suicide mortality rates by gender and occupation. The chi-square test, Fisher's exact test, and t-test were conducted to examine gender differences. Frequency and percentage distribution by gender and occupation were calculated using descriptive statistics. RESULTS: Regardless of gender, age-standardized suicide mortality rate was highest among "Managers." Women who died by suicide were significantly younger and more likely to be unmarried, live alone, and have fewer years of continuous employment than men. "Managers," "Professionals and Related Workers," and "Clerks" experienced similar work-related stresses, including "Difficult work to achieve," "Fail to achieve allocation workload," and "Change of job contents or workload." "Skilled Agricultural, Forestry and Fishery Workers," "Craft and Related Trades Workers," and "Equipment, Machine Operating and Assembling Workers" had higher work-related stress related to "Severe disease/injury" or "Causing a serious accident" compared with other workers. CONCLUSIONS: Work-related stress related to suicide deaths differed by gender and occupation. The gender gap of labor market participation in Korea may affect gender differences in terms of demographics and employment conditions among workers who died by suicide. Our study suggests that gender- and occupation-specific strategies and policies to reduce work-related stress can prevent suicide among workers.

Nationwide incidence and treatment pattern of retinopathy of prematurity in South Korea using the 2007-2018 national health insurance claims data.

The aim of this study is to investigate the nationwide incidence and treatment pattern of retinopathy of prematurity (ROP) in South Korea. Using the population-based National Health Insurance database (2007-2018), the nationwide incidence of ROP among premature infants with a gestational age (GA) < 37 weeks (GA < 28 weeks, GA28; 28 weeks ≤ GA < 37 weeks; GA28-37) and the percentage of ROP infants who underwent treatment [surgery (vitrectomy, encircling/buckling); retinal ablation (laser photocoagulation, cryotherapy)] were evaluated. We identified 141,964 premature infants, 42,300 of whom had ROP, with a nationwide incidence of 29.8%. The incidence of ROP in GA28 group was 4.3 times higher than in GA28-37 group (63.6% [2240/3522] vs 28.9% [40,060/138,442], p < 0.001). As for the 12-year trends, the incidence of ROP decreased from 39.5% (3308/8366) in 2007 to 23.5% (2943/12,539) in 2018. 3.0% of ROP infants underwent treatment (25.0% in GA28; 1.7% in GA28-37); 0.2% (84/42,300) and 2.9% (1214/42,300) underwent surgery and retinal ablation, respectively. The overall percentage of ROP infants who underwent treatment has decreased from 4.7% in 2007 to 1.8% in 2018. This first Korean nationwide epidemiological study of ROP revealed a decreased incidence of ROP and a decreased percentage of ROP infants undergoing conventional treatment during a 12-year period.

Increased risk of suicide after occupational injury in Korea.

OBJECTIVES: This study sought to investigate the association between occupational injury and subsequent risk of suicide in Korea. METHODS: We linked compensation data for 775 537 workers injured at work during 2003-2014 with National Death Registry through 2015. Suicide among injured workers was compared with the economically active population in Korea separately for men and women by calculating SMRs, with 95% CIs. RESULTS: Injured workers showed higher mortality from suicide for both men (SMR=2.22, 95% CI 2.14 to 2.31) and women (SMR=2.11, 95% CI 1.81 to 2.45) compared with the economically active population in Korea. CONCLUSIONS: Occupational injuries are associated with substantially elevated suicide risk in Korea. The results suggest the importance of social policies to protect and support injured workers as well as intensifying efforts to prevent workplace injuries.

Distribution of working position among workers with varicose veins based on the National Health Insurance and National Employment Insurance data.

BACKGROUND: This study aimed to determine the effect of specific working postures on the development of varicose veins (VV). By using Korea's National Health Insurance (NHI) and National Employment Insurance (NEI) data, we analyzed the general characteristic and difference in proportions of VV cases according to occupational working posture. METHODS: From the NEI and NHI data, participant demographics, such as gender, age, body mass index, and number of workers in specific occupations or industries were obtained. We classified the 240 occupations into blue-collar (BC) and white-collar (WC) occupations and subdivided them into standing, sitting, and walking groups according to the dominant working posture. RESULTS: The number of VV patients per 100,000 individuals increased with age, with a higher number of women than men and a higher number of patients in the BC than WC groups. For the BC group, the proportion of VV cases was the highest in the standing group, followed by the walking and sitting groups, but there was no significant difference between standing and walking groups in man. For the WC group, the standing group had a higher proportion of VV cases than the sitting group, but there was no significant difference between the standing and sitting group in man. In the BC group, the proportion of VV cases was the highest among medical and welfare-related elementary workers, bakers and cookie makers, automobile assemblers, cleaning and guarding-related elemental workers, and nurses and dental hygienists. In the WC group, the proportion of VV cases was the highest among food/lodging/tourism/entertainment/sports-related managers, environment/cleaning/protective services-related managers, finance and insurance clerks, accounting book-keeping clerks, and social welfare and counseling professionals. CONCLUSIONS: This study was performed to determine the characteristics of VV with different working posture among Korean workers. It is expected to be the basis of further studies on occupational musculoskeletal diseases.

Comparison between urban and rural mortality in patients with acute myocardial infarction: a nationwide longitudinal cohort study in South Korea.

OBJECTIVES: This study investigated the risk associated with interhospital transfer of patients with acute myocardial infarction (AMI) and clinical outcomes according to the location of the patient' residence. DESIGN: A nationwide longitudinal cohort. SETTING: National Health Insurance Service database of South Korea. PARTICIPANTS: This study included 69 899 patients with AMI who visited an emergency centre from 2013 to 2015, as per the Korea National Health Insurance Service database. PRIMARY OUTCOME MEASURE: The clinical outcome of a patient with AMI was defined as mortality within 7 days, 30 days and 1 year. RESULTS: Clinical outcomes were analysed and compared with respect to the location of the patient's residence and occurrence of interhospital transfer. We concluded that the HR of mortality within 7 days was 1.49 times higher (95% CI 1.18 to 1.87) in rural patients than in urban patients not subjected to interhospital transfer and 1.90 times higher (95% CI 1.13 to 3.19) in transferred rural patients than in non-transferred urban patients. CONCLUSIONS: To reduce health inequality in rural areas, a healthcare policy considering regional characteristics, rather than a central government-led, catch-all approach to healthcare policy, must be formulated. Additionally, a local medical emergency delivery system, based on allocation of roles between different medical facilities in the region, must be established.

Descriptive analysis of prevalence and medical expenses of cancer, cardio-cerebrovascular disease, psychiatric disease, and musculoskeletal disease in Korean firefighters.

BACKGROUND: 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.

Overwork-related disorders and recent improvement of national policy in South Korea.

OBJECTIVES: Recently, overwork-related disorders have become a major public health concern in Korea. This study investigated the current trends of working hours, causes of death in the working population, and compensation rates. METHODS: We reviewed the current trends of working hours, cause of death statistics in the working population, industrial accident compensation insurance (IACI) statistics, issues of compensation and prevention of work-related cerebro-cardio vascular diseases (CCVDs), mental disorders, and suicide. RESULTS: Although weekly working hours and the proportion of long working days have decreased, workers in small companies with fewer than five employees and those in the service sector continue to work long hours. The age standardized mortality due to CCVD and suicide was highest among those with managerial roles. In total, 589 CCVD cases and 104 mental disorder or suicide cases were compensated as occupational diseases in 2017. Between 2016 and 2017, 61% of 59 compensated suicides were related to overwork, specifically: long working hours, increased responsibility, or increased workload. The Korean government has introduced various policies to reduce working hours and to increase compensation approval rate for overwork-related CCVDs. Stakeholders have called for the introduction of independent laws to prevent overwork-related disorders, change organizational culture, and address the blind spots of the IACI Act and Labor Standard Act. CONCLUSIONS: Prevention and compensation policies have improved working conditions in Korea, but there remains much to be done. This review significantly contributes to the understanding of the overall policies and research to prevent overwork-related disorders in Korea.

Job Stress-attributable Burden of Disease in Korea.

BACKGROUND: As job stress is associated with various diseases and psychiatric conditions, we aimed to estimate the job stress-attributable burden of disease in Korea based on the concept of disability-adjusted life years (DALY). METHODS: We selected ischemic heart disease (IHD), stroke, major depressive disorder (MDD), and suicide as health outcomes from job stress, because of the ease of access to data estimating burdens and of important meaning of them in Korean occupational background. RESULTS: Our findings demonstrated that approximately 21% of Korean workers were exposed to high job strain, which was attributable for approximately 6.7% of IHDs, 6.9% of strokes, 13.6% of MDDs, and 4% of suicides. In terms of job stress-attributable DALY, the burdens of disease per 100,000 people were 38 for IHD, 72 for stroke, 168 for MDDs, and 44 for suicides. CONCLUSION: The present findings suggested that one-fifth of Korean workers were suffering from high job strain. Although the figures may not be accurate due to several assumptions, job stress is an important risk factor for health in working environment in Korea.

Dosimetric effects of the acuros XB and anisotropic analytical algorithm on volumetric modulated arc therapy planning for prostate cancer using an endorectal balloon.

BACKGROUND: To compare the dosimetric effects of Acuros XB (AXB) and Anisotropic Analytical Algorithm (AAA) on volumetric modulated arc therapy (VMAT) planning for postoperative prostate cancer patients irradiated using an endorectal balloon (ERB). METHODS: We measured central axis doses with film in a phantom containing an air cavity, and compared measurements with calculations of the AAA and AXB. For clinical study, 10 patients who had undergone whole pelvic radiotherapy (WPRT) followed by prostatic bed-only radiotherapy (PBRT) using VMAT were enrolled. An ERB was used for PBRT but not for WPRT. To compare dosimetric parameters, the cumulative dose-volume histograms, mean, maximum, and minimum doses were measured for the planning target volume. Homogeneity of plans were confirmed using V95%, V107% (VX%, percentage volumes receiving at least X% of prescribed doses) and conformity indices (homogeneity index [HI], conformity index [CI], and conformation number [CN]). We compared volumes of the organ-at-risk receiving 10% to 100% (10-tier at 10% interval) of prescribed doses (V10% - V100%). RESULTS: In the phantom study, the AAA showed larger disagreement with the measurements, and overestimated the dose in the air cavity, comparing with the AXB. For WPRT planning, the AAA predicted a lower maximum dose and V107% than the AXB. For PBRT planning, the AAA estimated a higher minimum dose, lower maximum dose, and smaller V107%, and larger V95% than the AXB. Regarding the conformity indices, the AAA was estimated to be more homogenous than the AXB for PBRT planning (HI, 0.088 vs. 0.120, p = 0.005; CI, 1.052 vs. 1.038, p = 0.022; and CN, 0.920 vs. 0.900, p = 0.007) but not for WPRT planning. Among V10% to V100% of the rectum, the PBRT exhibited significant discrepancies in V30%, V40%, V70%, V80%, and V90%; while the WPRT did in V20% and V30%. CONCLUSIONS: The phantom study demonstrated that the AXB calculates more accurately in the air cavity than the AAA. In the clinical setting, the AXB exhibited different dosimetric distributions in the VMAT plans for PBRT containing an ERB. The AXB should be considered for prostate cancer patients irradiated with an ERB for better applying of heterogeneous condition.