Clinical Psychological Science, Ahead of Print.
Assessing youth psychopathology involves collecting multiple informants’ reports. Yet multi-informant reports often disagree, which necessitates integrative strategies that optimize predictive power. The trait-score approach leverages principal components analysis to account for the context and perspective from which informants provide reports. This approach may boost the predictive power of multi-informant reports and thus warrants rigorous testing. We tested the trait score approach using multi-informant reports of adolescent social anxiety in a mixed clinical and community sample of adolescents (N = 127). The trait score incrementally predicted observed social anxiety (βs = 0.47–0.67) and referral status (odds ratios = 2.66–6.53) above and beyond individual informants’ reports and a composite of informants’ reports. The trait score predicted observed behavior at magnitudes well above those typically observed for individual informants’ reports of internalizing psychopathology (i.e., rs = .01–.15). Findings demonstrate the ability of the trait score to improve prediction of clinical indices and potentially transform widely used practices in multi-informant assessments.