Parent/Guardian- and Self-Report Versions of the Irritability Domain of the Concise Associated Symptom Tracking Scale: Evaluation of Psychometric Properties and Potential Clinical Utility in the Texas Youth Depression and Suicide Research Network

Objective

This report evaluated how self- vs parent/guardian-report of irritability, a common transdiagnostic feature of mental illness in children and adolescents, relate to each other, and whether there are any differences based on sex.

Method

Individuals (aged 8-17 years) from the ongoing Texas Youth Depression and Suicide Research Network (TX-YDSRN) with data available for self- and parent/guardian-versions of the 5-item irritability domain of Concise Associated Symptom Tracking (CAST-IRR) as a measure were included (N=658). Confirmatory factor analyses (CFAs) and item response theory (IRT) analyses evaluated psychometric properties for the full sample and for male and female participants separately. Weighted kappa statistics evaluated the agreement, and bifactor analysis evaluated shared vs unique components of the 2 versions.

Results

Both self- and parent/guardian-report versions of CAST-IRR had similar psychometric properties in the full sample as well as in male and female participants separately. The slope of each item exceeded 1.0 on IRT analyses, suggesting adequate discrimination for each item. There was poor agreement for items of self- and parent/guardian versions (weighted kappa range, 0.07-0.21). Self- and parent/guardian-report versions were significantly correlated with other self- and parent/guardian-report measures of depression and anxiety, respectively. A bifactor model supported the presence of a shared factor as well as unique self- and parent/guardian-specific factors that explained 40.8%, 14.2%, and 45.0% variance, respectively.

Conclusion

Self- and parent/guardian-report versions of CAST-IRR have similar psychometric properties in both male and female participants, and measure distinct aspects of irritability in youths. Clinicians may consider using both versions in their practice to comprehensively assess irritability.

Plain language summary

This study from the Texas Youth Depression and Suicide Research Network evaluated the psychometric properties and agreement between youth-report and parent/guardian-report versions of an irritability questionnaire for youth, the Concise Associated Symptom Tracking-Irritability scale (CAST-IRR). The psychometric properties of both scales were similar, though agreement between youth and parents/guardians was low. CAST-IRR measured both a shared factor of irritability between youth and parents/guardians, as well as unique factors of irritability for the youth and the parents/guardians. Given the importance of irritability in youth psychopathology, further work is needed to determine the value of considering both self- and parent/guardian reports.