This study examines the factors influencing item nonresponse, especially when it comes to income and sexual behavior, in the Japanese context. Many item nonresponses on questions on income and sexual behavior are a serious problem for analysis since they might cause biased estimations. However, many previous studies on item nonresponse when it comes to income and sexual issues examine surveys carried out in Western societies. Moreover, many previous studies have not distinguished between “Refused” and “Don't Know.” In addition, many previous studies on income nonresponse do not focus on the effect of religion, although questions on religion have been argued to affect survey cooperation. Thus, we analyzed the data from the Japanese General Social Survey 2000/2001 to distinguish the reason for nonresponse properly, reveal factors on income and sexual behavior nonresponses, and examined the effect of religion. We conducted multinomial logistic regressions of nonresponse in household income, individual income, and sexual behavior. Our findings are as follows: (1) Factors that affected nonresponses of income and sexual behavior are different between Japanese and Western societies. (2) The effect of age and educational background are different between “Refused” and “Don't Know.” (3) Respondents whose family has a religion tended to answer with household income. These findings indicate that we should consider the nonresponse mechanism due to the Japanese-specific context, distinguish the reason for nonresponse because of different effects of factors, and focus on the effect of religion on income nonresponse.
