-Factor(s) for Youth Psychopathology Across Informants and Models in 24 Societies.

Objective: Although the significance of the general factor of psychopathology ( is being increasingly recognized, it remains unclear how to best operationalize and measure . To test variations in the operationalizations of and make practical recommendations for its assessment, we compared -factor scores derived from four models.

Methods: We compared scores derived from principal axis (Model 1), hierarchical factor (Model 2), and bifactor (Model 3) analyses, plus a Total Problem score (sum of unit-weighted ratings of all problem items; Model 4) for parent- and self-rated youth psychopathology from 24 societies. Separately for each sample, we fitted the models to parent-ratings on the Child Behavior Checklist for Ages 6-18 (CBCL/6-18) and self-ratings on the Youth Self-Report (YSR) for 25,643 11-18-year-olds. Separately for each sample, we computed correlations between scores obtained for each pair of models, cross-informant correlations between -scores for each model, and -correlations between mean item x -score correlations for each pair of models.

Results: Results were similar for all models, as indicated by correlations of .973-.994 between -scores for Models 1-4, plus similar cross-informant correlations between CBCL/6-18 and YSR Model 1-4 -scores. Item x correlations had similar rank orders between Models 1-4, as indicated by correlations of .957-.993.

Conclusions: The similar results obtained for Models 1-4 argue for using the simplest model - the unit-weighted Total Problem score - to measure for clinical and research assessment of youth psychopathology. Practical methods for measuring may advance the field toward transdiagnostic patterns of problems.