Junko Kawahito

Employment Type, Workplace Interpersonal Conflict, and Insomnia: A Cross-sectional Study of 37,646 Employees in Japan

ABSTRACT. This study explored whether workplace interpersonal conflict (WIC) is associated with insomnia, and whether the relationship between WIC and insomnia differs across different employment groups. A total of 37,646 Japanese full-time employees participated in a cross-sectional survey. Employment types included permanent employment and 2 forms of temporary employment: direct-hire and temporary work agent (TWA). Insomnia symptoms, including difficulty initiating sleep, difficulty maintaining sleep, and early morning awakening were measured. Insomnia was defined as having experienced 1 or more of these symptoms on ≥3 nights per week over the past 12 months. Results showed that WIC was significantly associated with an increased risk of insomnia (odds ratio OR = 1.63; 95% confidence interval CI = 1.55–1.71), controlling for confounders. However, the relationship between WIC and the risk of insomnia was significantly stronger for TWAs than for permanent employees (OR = 1.97; 95% CI = 1.13–3.45). A frequent exposure to WIC may increase the risk of insomnia, particularly for TWAs.

日本語版The Positive and Negative Affect Schedule (PANAS)20項目の信頼性と妥当性の検討

本研究は,日本語版The Positive and Negative Affect Schedule (PANAS)の20項目の信頼性と妥当性を検討することが目的であった。大学生442名を対象に質問紙調査を実施した。因子分析により,ポジティブ感情(10項目)とネガティブ感情(10項目)の2因子構造が示された。妥当性は,人生に対する満足尺度,主観的幸福感尺度,自己記入式抑うつ性尺度,状態不安検査との相関を用いて検討した。その結果,ポジティブ感情は,人生に対する満足尺度および主観的幸福感尺度との問に正の相関関係を示した。他方,ネガティブ感情は,自己記入式抑うつ性尺度および状態不安検査との間に正の相関関係を示した。信頼性は,内的整合性とI-T相関の結果から,信頼性の高さが示された。以上から,日本語版PANAS20項目の信頼性と妥当性が確認された。

Association of Suicidal Ideation with Job Demands and Job Resources: a Large Cross-Sectional Study of Japanese Workers

PurposeThis study aimed to identify the association of suicidal ideation with job demands and job resources among Japanese workers.MethodsValid data from questionnaires that were pre-collected from 42,499 workers (34,882 males and 7617 females) were used for multilevel logistic regression analyses. Job demands and job resources were selected as potential predictors of suicidal ideation. Lifestyle variables, support from family and friends, and suffering from depressive or eating disorders were used as covariates.ResultsIn the employee-level, most job demands and job resources had significant associations with the risk of suicidal ideation in both sexes. High coworker support had a significant negative association with the risk of suicidal ideation in the organization-level, irrespective of their gender. High physical demands and poor physical environment in the organization-level had significant positive associations with increased risk of suicidal ideation only among females.ConclusionsThe risk of suicidal ideation among Japanese workers is associated with job demands and job resources in the employee-level, and coworker support in the organization-level may be important as well.

Development of a Japanese version of the Perceived Vulnerability to Disease Scale

This study developed a Japanese version of the Perceived Vulnerability to Disease (PVD) scale. Analysis of the data from Japanese university students (N = 435) replicated the two-factor structure of the original scale: one factor that assessed beliefs about ones own susceptibility to infectious diseases (perceived infectability) and the other factor that assessed emotional discomfort in contexts that connoted an especially high potential for pathogen transmission (germ aversion). Tests of reliability and validity for each subscale indicated overall promising results. It would appear that the results reflect at least in part an evolutionary adaptive psychological mechanism for the ancestral environment.