Since the night time work was introduced as a ‘harmful factor’ for the worker's special health examination (WSHE) in 2014, the validation of the questionnaire used for screening gastrointestinal (GI) disorder has not been conducted. The purpose of this study is to verify the validity of the questionnaire using the data of specific health screening cluster.

We used WSHE screening data for 3 years, from 2014 to 2016, in health screening cluster. The subjects who had received upper GI endoscopy in opportunistic screening and WSHE simultaneously regardless of the results of the questionnaire were selected. We tested the validity of the questionnaire using upper GI endoscopy as a gold standard.

This study was conducted on 5,057 examinees in 2014, 8,352 examinees in 2015, and 10,587 examinees in 2016. The validity of the questionnaire for each year was as follows: sensitivity 12.3% (95% confidence interval [CI], 11.1–13.4), specificity 88.6% (95% CI, 87.2–90.1), accuracy 41.1% (95% CI, 39.8–42.5) in 2014, sensitivity 5.9% (95% CI, 5.2–6.5), specificity 93.6% (95% CI, 92.7–94.4), accuracy 38.6% (95% CI, 37.6–39.6) in 2015, sensitivity 6.0% (95% CI, 5.4–6.5), a specificity of 9.42% (95% CI, 93.4–95.0), accuracy of 34.2% (95% CI, 33.3–35.1) in 2016. In generally, questionnaire showed sensitivity of 10%, specificity of 90%, and accuracy of 40%.

Despite the purpose of WSHEs aiming to identify target disease early, the sensitivity of the questionnaire for GI disease was too low as 10%. The reasons for this are the problem of the question itself, and the problem of ambiguous target disease. In the future, the questionnaire should be improved to meet the purpose of the WSHE, and further correction of the target disease should be made.

Health examinations are performed so that diseases can be identified and treated earlier. Several studies have evaluated the determinants of participation in health examinations including cancer screening, but few have evaluated the relationship between the size of the enterprise and their participation in Workers’ General Health Examinations (WGHE). The aim of the present study was to estimate the association of WGHE participation with the size of the enterprise and the type of policyholder.

The eligible population from 2006 through 2013 was extracted from the National Health Insurance Service (NHIS) database. The population size ranged from 14–17 million. After adjustment for age and gender, multiple logistic regression analysis was performed to estimate the odds ratios of participating in the WGHE (by age group) based on the type of policyholder (reference: public officers) and the size of the enterprise (reference: enterprise size ≥300 employees), respectively.

Workers employed at enterprises with <50 persons were less likely to participate in WGHEs than those employed at enterprises with ≥300 persons. After policyholders were stratified by type (non-office workers vs. public officers), a disparity in the WGHE participation rate was found between the different types of policyholders at enterprises with <50 employees (reference: those employed at enterprises with ≥300 employees); the odds ratios for subjects in their 40s and 50s were 0.2–0.3 for non-office workers vs. 0.8–2.0 for public officers.

Workplace policyholders at small enterprises comprised a vulnerable group less likely to participate in WGHEs. Efforts should be made to raise the WGHE participation rate among the vulnerable employees belonging to small enterprises, as well as among their dependents.

An association between silica exposure and autoimmune diseases including rheumatoid arthritis, systemic sclerosis, systemic lupus erythematosus, and anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis has been made.

A 56-year-old male presented with silicosis and had an occupational history of precious metal processing for 30 years and a 30 pack-year smoking history. The patient was diagnosed with pneumoconiosis and received compensation. No other complications were reported for pneumoconiosis. The patient suddenly presented with a non-specific headache for several days and microscopic hematuria was identified upon examination in the outpatient clinic. Following several weeks, the patient presented with aggravated dyspnea and hemoptysis, and his Modification of Diet in Renal Disease estimated glomerular filtration rate indicated acute kidney injury. Diagnostic analysis revealed perinuclear ANCA-associated microscopic polyangiitis (p-ANCA-associated MPA).

Exposure to silica dust was likely one of the cause of p-ANCA-associated MPA. Possible pathogenic mechanisms of autoimmune diseases in silicotics and emphasis of the necessity for early diagnosis are discussed.