In adolescence, help-seeking is affected by different actors. The influence of each actor on help-seeking is often studied in isolation, or, if multiple informants are included, using only few assessments of adolescents’ mental health.

The aim of this study is to determine the extent to which self-, parent- and teacher-reported problem behavior predict secondary care in adolescence and to what extent the informants’ relative importance changes over time.

Data from the Dutch community-based cohort study tracking adolescents’ individual lives survey (TRAILS) were linked to administrative records of secondary care from 2000 (age 9) to 2011 (age 21). Internalizing and externalizing problems were assessed using the youth self-report, child behavior checklist and teacher checklist of psychopathology at ages 11, 13 and 16, and the adult self-report at age 19.

The annual incidence of secondary care fluctuated between 1.3% and 2.4%. In Cox regression analyses that adjusted for sociodemographic covariates and problem behavior, internalizing problems but not externalizing problems predicted secondary care. Secondary care between the ages 11 to 13 years was predicted best by teachers, between the ages 13 to 16 by parents, and between the ages 16 to 21 by adolescents.

The relative importance of informants for predicting secondary care shifts over time, which suggests that each informant is the driving force behind secondary care at a different phase of adolescence. The treatment gap may be reduced by improving problem recognition of teachers in secondary education and by educating young adults about mental health problems.