The long-term association between paternal involvement in infant care and children's psychological well-being at age 16 years: An analysis of the Japanese Longitudinal Survey of Newborns in the 21st Century 2001 cohort

Background: Some studies conducted in the United Kingdom have shown long-term associations between paternal involvement in childcare and adolescents' mental health issues. However, findings were inconsistent, and similar epidemiologic studies have not been conducted in other countries in Europe or Asia. Thus, we aimed to examine this association using Japanese population-based cohort study data.Methods: The Japanese Longitudinal Survey of Newborns in the 21st Century commenced in 2001. Data from 18,568 16-year-olds enrolled in the survey were analyzed. Poor psychological well-being was assessed using the WHO-5 Well-being Index. Paternal involvement in childcare-in tasks such as changing diapers-was assessed at the children's 6 months of age. We created four groups from least involvement to most active involvement based on the frequency of fathers' performing the tasks.Results: The risk of poor psychological well-being was lower among more active involvement groups compared with the least involvement group, after adjusting for potential confounders (risk ratios = 0.90 [95 % confidence intervals: 0.85, 0.95] for the most active group). Limitations: Due to 16 years of follow-up, loss to follow-up may have caused a selection bias.Conclusions: Our study is the first in Asian countries to show that fathers' active involvement in childcare is associated with poor psychological well-being in adolescence. Encouraging fathers' involvement in childcare may ameliorate prevalent issues of school refusals and withdrawals in the long term in Japan.