Associations among hair cortisol-to-DHEA ratio, psychological capital, harsh parenting, and internalizing problems in adolescence

Abstract

Introduction Internalizing problems are increasingly prevalent among Chinese students in junior high school, and posing significant risks for long-term maladjustment. However, the mechanisms underlying these problems are unclear. The present study aimed to test the moderating effects of psychological capital and harsh parenting in the association between the hair cortisol-to-DHEA (C/D) ratio and internalizing problems in adolescence. Methods 282 junior high school students in China participated in this study (114 boys, 166 girls, and 2 with missing sex data; M age = 12.82 years). They provided hair samples and completed questionnaires on psychological capital, internalizing problems, harsh parenting of their parents, and control variables including sex, age, family socioeconomic status, negative life events, and body mass index. Hair concentrations of cortisol and DHEA were determined via liquid chromatography-tandem mass spectrometry. Results The main effect of the hair C/D ratio on internalizing problems was not significant. The interaction between the C/D ratio and psychological capital was significant. Simple slope analysis revealed that a higher C/D ratio predicted fewer internalizing problems among adolescents with high psychological capital, but not among those with mean or low psychological capital. The three-way interaction involving harsh parenting was marginal after correction for multiple testing. Conclusion Psychological capital moderates the association between the hair C/D ratio and adolescent internalizing problems. These findings highlight psychological capital as a potential intervention target for promoting adaptive stress responses in adolescents.

The authors' abstract, as published at the source. Frontiers in Psychology, 2026 · DOI ↗