Participants

The present analyses are based on cross-sectional data from the first survey of the Japanese Study of Stratification, Health, Income, and Neighborhood (J-SHINE, 2011). J-SHINE is an ongoing epidemiological household panel study, representing residents aged 25-50 years in metropolitan Tokyo and neighboring areas. The Internal Review Board of The University of Tokyo approved the study protocol (approval number 3073). Secondary use of the data was approved by the data management committee of the J-SHINE research group, with personally identifiable information deleted to ensure confidentiality. Further details on J-SHINE can be found elsewhere²⁰⁾. The surveys were computer-based and self-administered unless the participants requested a face-to-face interview. We used the data from the first-wave study, which was performed from July 2010 to February 2011. The area covered four municipalities in and around Tokyo (two in the Tokyo metropolitan area and two in neighboring prefectures). Stratified random sampling of residents aged 25-50 years was performed to form a group of subject regional citizens. Of the 13,920 residents to whom surveys were sent, information was collected from 4,385 (response rate: 31.5%). We excluded those who did not provide valid responses to questions about age, sex, marital status, family members, educational attainment, household income, self-rated health, physical activity, smoking status, alcoholic status, hours worked per week, job stress, health literacy, type of employment, company size, occupation type, experience refraining from seeking medical services, and use of medical services in the preceding year. Fig. ​Fig.11 shows the flow of inclusion for subjects in the present study.

Inclusion flow of study participants from the Japanese Study on Stratification, Health, Income, and Neighborhood (J-SHINE)