Toward Validating a Measure of Tonic and Phasic Irritability in Community and Clinical Samples - Project Summary/Abstract Irritability is one of the most common mental health problems in children and adolescents. Moreover, it is one of the strongest predictors of later psychopathology and functional impairment in adulthood. Irritability can manifest in a variety of ways, which has recently led some investigators to conceptualize it as consisting of two components: tonic irritability, defined as persistently angry or grumpy mood; and phasic irritability, defined as short-lived temper outbursts. Though this distinction has been raised conceptually, research examining whether tonic/phasic irritability are empirically separable and differ in their clinical correlates, underlying mechanisms, longitudinal course, and treatment response is limited. A significant obstacle for empirical work in this area has been that no psychometrically validated measure that differentiates between tonic/phasic irritability is currently available for research or clinical use. Long-term objectives. I propose to develop and evaluate the first multi-informant measure of tonic/phasic irritability for school-age children and adolescents. This measure will fill an urgent gap in the literature by providing a psychometrically-sound, multi-informant instrument that will advance research on the etiopathogenesis of tonic/phasic irritability and help develop and evaluate targeted approaches to prevention and treatment. Design. I developed the tonic/phasic scale by 1) conducting a comprehensive literature search of existing instruments that cover related constructs, 2) utilizing experts in developmental psychopathology to revise and refine the item pool, and 3) conducting cognitive interviews with parents of children and adolescents using a combined think-aloud and debriefing methodology. The proposed project will collect data from five samples including three convenience community samples (a total of ~800 parents of 6–17-year-old children and ~800 unrelated 13–17-year-old youth) collected through Qualtrics XM panels, allowing for an iterative scale development process; a longitudinal dataset (~215 parents of 6-year-olds enriched for irritability) with a wider set of validating measures; and a clinical sample (~150 parents and their ~150 10–17-year-old children in outpatient psychology and psychiatry clinics) to evaluate the generalizability of the measure to a more severely impaired population. In each sample, participants will complete a brief survey assessing irritability and emotional and behavioral symptoms. Aims/Methods. The aims of this project are five-fold: 1) develop and refine a novel multi-informant scale for assessing youth tonic/phasic irritability using classical psychometric and item-response theory (IRT) analyses; 2) evaluate convergent and discriminant validity by examining concurrent relationships of tonic/phasic irritability with existing measures of irritability, parental psychopathology, parenting style, child temperament, and child psychopathology; 3) assess predictive validity by modeling relationships between tonic/phasic irritability and later measures of youth psychological problems; 4) evaluate measurement invariance for informant, age, biological sex, and race/ethnicity; and 5) develop a shortened version of the rating scale using IRT.
