Background: Studies of secular trends in mental unhealth indicate that adolescents in the Nordic countries, especially girls, have an increased reported prevalence of mental health problems the last decades. This increase needs to be seen in the light of the adolescents' assessments of their perceived overall health.Objective: To investigate whether a person-centered approach to research can enhance understanding of changes over time in the distribution of mental health problems among Swedish adolescents.Method: A dual-factor approach was used to study changes over time in mental health profiles among nationally representative 15-year-old adolescent samples from Sweden. Cluster analyses of subjective health symptoms (psychological and somatic) and perceived overall health from the Swedish Health Behavior in School-aged Children (HBSC) surveys of 2002, 2006, 2010, 2014, and 2018 were used to identify these mental health profiles (n = 9,007).Results: Four mental health profiles were identified by a cluster analysis which combined all five data collections—Perceived good health, Perceived poor health, High psychosomatic symptoms, and Poor mental health. There were no significant differences in the distributions of these four mental health profiles between the survey years 2002 and 2010, but substantial changes took place between 2010 and 2018. Here, particularly the High psychosomatic symptoms profile increased among both boys and girls. The Perceived good health profile decreased among both boys and girls, and the Perceived poor health profile decreased among girls. The profile involving the most pronounced mental health problems, the Poor mental health profile (perceived poor health, high psychosomatic problems), was stable from 2002 to 2018 among both boys and girls.Conclusion: The study shows the added value of using person-centered analyses to describe differences in mental health indicators between cohorts of adolescents over longer periods of time. In contrast to the long-term increase in mental health problems seen in many countries, this Swedish study did not find an increase among young persons, both boys and girls, with the poorest mental health, the Poor mental health profile. Rather, the most substantial increase over the survey years, predominantly between 2010 and 2018, was found among the 15-year-olds with High psychosomatic symptoms only.

Relatively few studies have predicted adolescent or adult delinquency from childhood Rorschach data. Incremental validity of Rorschach measures over other known consistent and more easily obtained predictors has typically not been investigated. We addressed Rorschach data's incremental validity over mother's reports of externalizing behavior and mother-child relations for predicting officially registered adolescent and adult delinquency in a longitudinal study of 122 Swedish men. The Rorschach measures we used were aggregates of blind, prospectively performed, global expert ratings based on a holistic evaluation of protocols. An aggregate of Rorschach-based ratings of ego strength significantly improved the prediction of delinquency in adolescence and adulthood over and above earlier identified best predictors (mother's ratings of mother-child relations and externalizing problem behavior).