10 years old was significantly higher in the prosocial praise group than in the other praise group (7.1 ± 2.0 vs. 6.5 ± 2.0, p < 0.001). The estimated IQ at age 10 tended to be lower in the prosocial praise group (107.2 ± 13.9 vs. 108.0 ± 14.1, p = 0.16). There were no significant differences in the age of children, age of caregivers, psychological distress of primary caregivers (K6 scores), educational background of caregivers, or household income between the two groups.
The Association Between Prosocial Self-Reports at 10 Years of Age and Depressive Symptoms at 12 Years of Age
Table 2 shows the results of simple linear regression analysis and multiple linear regression analyses to investigate the longitudinal relationship between prosocial self-reports and depressive symptoms in children. In the single regression analysis, the children who reported being praised for prosocial behavior at age 10 had significantly lower depressive symptoms at age 12 [partial regression variable: −0.57, 95% confidence interval (CI): −0.96 to −0.17, p < 0.01]. In the multiple regression analysis, in addition to the child's age and sex, objective prosocial behavior, the estimated IQ and the number of siblings were added as confounders because they were significantly different between the prosocial praise group and the other praise group (Table 1). Caregivers' age and education, annual household income, and psychological distress of primary caregiver (K6 scores) were excluded from confounders because there were no significant differences between the prosocial praise and other praise groups. Statistical analysis was performed after missing values were complemented by multiple substitution. Even after adjusting for confounders, being praised for prosocial behaviors at 10 years of age was significantly associated with lower depressive symptoms at 12 years of age (partial regression variable: −0.44, 95% CI: −0.80 to −0.08, p < 0.05). There was no evidence for the interaction effect of sex and prosocial self-report on depressive symptoms (p = 0.22).
Table 2. The association between being praised for prosocial behaviors at age 10 and depressive symptoms at age 12.
This is the first study that investigated the longitudinal relationship between the perceived experience of being praised for prosocial behaviors and depressive symptoms using a large-scale cohort of early adolescents from the general population. Based on the multiple linear regression analyses, the self-report of being praised for prosocial behaviors at 10 years old, but not objective prosocial behavior, predicted lower depressive symptoms 2 years later even after adjusting for baseline depressive symptoms.
Self-report of being praised for prosocial behavior predicted lower depressive symptoms 2 years later in adolescents. Being praised for prosocial behavior means being praised for behavior (process) and being praised for altruism, both of which can be preventive against depression. According to the theory about praise, process praise maintains self-esteem (2). Additionally, prosociality can be preventive against depression. A previous study suggested that helping others may increase self-acceptance and self-confidence and consequently improve depression (21).
Furthermore, rather than objective prosocial behavior alone, being praised for prosocial behavior decreased future depressive symptoms in adolescents. There may be several explanations for the findings of the present study. First, being praised might be an important process of fostering self-acceptance and self-confidence as a result of prosocial behaviors. Being praised might strengthen the recognition of adolescents' prosocial behaviors, which then leads to self-acceptance. Second, being praised might prompt further prosocial behavior and attitudes, which then leads to self-acceptance. Third, this study results may reflect the relatively strong relationship between interdependent self-construal and depressive symptoms in the Japanese culture (22). Being praised for prosocial behavior might affect self-construal stronger than th