Is Japan’s child allowance effective for the well-being of children? A statistical evaluation using data from K-CHILD study

Background Child allowance payment is one form of social security policy that aims to mitigate the child poverty gap by providing financial support to families. This study aimed to explore the impact of the child allowance on children’s physical and mental health (BMI, problem behavior, depression, and self-rated health), and parental investment in child health (children’s material goods, family events, extracurricular activities, interaction with children, and involvement in child maltreatment). Methods We used cross-sectional data from the 2016 Kochi Child Health Impact of Living Difficulty (K-CHILD) study. Participants were 1st, 5th and 8th grade children living in Kochi prefecture in Japan (N = 8207). Caregivers reported children’s child allowance status, BMI and behavior problems, while children filled out a self-assessment on depression and health condition. Propensity score matching analysis regarding potential confounders was used. Results We found that children in families that received child allowance showed a smaller total difficulties score by 1.29 points (95% CI: − 2.32 to − 0.25) and a lower risk of overweight (OR: 0.51, 95% CI: 0.29 to 0.91) although there is no association with underweight, prosocial behavior, depressive symptoms and self-rated health. Parental investment did not differ by child allowance status (p > 0.05). Conclusions Child allowance was found to be potentially beneficial in decreasing behavior problems and reducing child overweight. Further longitudinal studies are needed to elucidate how child allowance is used by family members and associated with children’s well-being. (230/350 words)