Temperament, Personality, and Psychopathology in Youth: A Preregistered Multilevel Meta-Analytic Review and Preregistered Large-Scale Replication and Extension

The current pair of highly-powered, preregistered studies estimate the associations between personality/temperament and youth psychopathology, and evaluate the generalizability of these associations across diverse populations and research designs. In Study 1, a multilevel meta-analysis of 147 studies (k effects = 829, N = 46,369) quantified the cross-sectional associations among subjects aged 1.5 to 18, between Five-Factor Model personality traits and internalizing/externalizing psychopathology dimensions within the Achenbach System of Empirically Based Assessments (ASEBA; Achenbach & Rescorla, 2001). All traits but openness evidenced bivariate associations with both psychopathology dimensions (r = |0.18 – 0.42|). After adjusting for the covariance between internalizing and externalizing, each dimension showed a distinct personality profile. Internalizing was associated with neuroticism (β = 0.42) and negative-extraversion (β = −0.37). Externalizing was associated with extraversion (β = 0.30), negative-conscientiousness (β = −0.46), and negative-agreeableness (β = −0.50). Most variance was driven by informant effects, particularly within the externalizing dimension and when personality and psychopathology were informed by the same person (i.e., mono-informant). Study 2 was a preregistered replication and extension of Study 1 in a large, demographically diverse cohort of 9–10 year-olds (N = 10,414; excluding diagnoses of schizophrenia, autism spectrum disorders, and substance use disorders) using cross-sectional, individual-participant, item-level data, and measures of temperament corollary to Study 1 personality traits. Most of Study 1’s personality associations with ASEBA’s internalizing and externalizing dimensions were replicated for higher-order temperament scales (e.g., Effortful Control) and for their lower-order scales (e.g., Activation Control). Again, mono-informant effects were more pronounced than cross-informant effects. Taken together, these studies provide the first quantitative synthesis of robust cross-sectional associations between personality and psychopathology in youth, highlight the impact of mono-informant effects. Future longitudinal research may parse out directional relations as well.