Background: Tracking clinical outcomes during therapy can be useful for improving both clinical practice and research. For repeated data collection, short, reliable, and valid measures of central aspects of psychopathology are necessary. The current paper investigates the psychometric properties of two short surveys for measuring central dimensions of psychopathology in youth. Methods: We investigated factor structure and validity of the Norwegian translations of the Behavior and Feelings Survey (BFS) and the Brief Problem Monitor (BPM). The BFS has previously shown a two-factor structure and indications of validity as a measure of internalizing and externalizing problems in youth. Likewise, the BPM has support for a three-factor structure of internalizing, externalizing and attention problems. In our sample of 503 youths and caregivers in a Norwegian outpatient clinic, we conducted confirmatory factor analyses to test the assumed measurement models and further considered concurrent validity of the measures. Results: The results suggest that the assumed measurement models for both questionnaires only partly fit our data but that subscales of the BFS and BPM still indicate convergent validity. Conclusions: Alternative measurement models, and the usefulness and limitations of these short form questionnaires for internalizing and externalizing problems, are discussed.

Background Tracking clinical outcomes during therapy can be useful for improving both clinical practice and research. For repeated data collection, short, reliable, and valid measures of central aspects of psychopathology are necessary. The current paper investigates the psychometric properties of two short surveys for measuring central dimensions of psychopathology in youth. Methods We investigated the factor structure and validity of the Norwegian translations of the Behavior and Feelings Survey (BFS) and the Brief Problem Monitor (BPM). The BFS has previously shown a two-factor structure and indications of validity as a measure of internalizing and externalizing problems in youth. The BPM has support for a three-factor structure of internalizing, externalizing, and attention problems. In our sample of 503 patients (56% female, age 6 to 18) in a Norwegian outpatient clinic, we conducted confirmatory factor analyses to test the assumed measurement models and further considered the concurrent validity of the measures. Results Internal reliability of both measures were good. The results suggest that the assumed measurement models for both questionnaires only partly fit our data but that subscales of the BFS and BPM still indicate convergent validity. Scores on subscales (internalizing and externalizing problems) on both measures converged with relevant subscales as well as with relevant groups of diagnoses. Conclusions Alternative measurement models, and the usefulness and limitations of these short-form questionnaires for internalizing and externalizing problems, are discussed.