Frequency of Organised Enrichment Activities and Later Self‐Esteem in Japanese Children: A Longitudinal Cohort Study

BACKGROUND: Although participation in organised extracurricular activities has been associated with higher self-esteem, high participation frequency may have adverse effects, as proposed by the overscheduling hypothesis. Longitudinal evidence from non-Western countries is limited. We examined whether the frequency of enrichment-oriented out-of-school lessons (naraigoto) in fourth grade was associated with self-esteem in sixth grade in a Japanese large-scale cohort. METHODS: We analysed longitudinal data from the Japanese Longitudinal Study of Children and Parents from fourth grade (baseline, 2017-2019) to sixth grade (follow-up, 2019-2021) (n = 3399). The exposure was the frequency of enrichment-oriented activities in fourth grade, excluding academic tutoring (juku). The outcome was self-confidence in sixth grade (4-point Likert scale). Ordinal logistic regression models were employed for estimating odds ratios and 95% confidence intervals, and possible confounders (sociodemographic factors, baseline self-confidence) were adjusted. Sensitivity analyses were also conducted using alternative outcome and alternative exposure definitions. RESULTS: In the fully adjusted model, the adjusted odds ratios for higher self-confidence were 1.22 (95% confidence interval 0.96-1.55) for one session/week, 1.30 (1.02-1.66) for two sessions/week, 1.34 (1.04-1.73) for three session/week, 1.41 (1.10-1.82) for four to five sessions/week, and 1.22 (0.87-1.71) for six or more sessions/week, compared with zero sessions/week (reference). Associations were strongest at two to five sessions/week, with no increase at six or more sessions/week. Results were similar in sensitivity analyses. Gender-stratified analyses suggested that these associations were significant only in male participants. CONCLUSIONS: Enrichment activity participation was associated with self-esteem 2 years later, with the strongest associations at moderate frequencies. Future studies should examine total amount of time and qualitative aspects of participation.