How EASI can it be? Closing the research-to-practice gap via population-based validation of the MAPS-EASI 2.0 early childhood irritability screener for translation to clinical use.

Dysregulated irritability is the most robust early childhood transdiagnostic predictor of psychopathology. However, this evidence has failed to translate to practice due to a dearth of efficient, developmentally-based screening tools. Drawing on the well-validated Multidimensional Assessment Profiles (MAPS) Temper Loss Scale, early feasibility testing of a preliminary clinical screener (MAPS-Early Assessment Screener for Irritability; MAPS-EASI 1.0) was well-received. However, large-scale clinical implementation requires enhanced precision, with age-banded norms psychometrically derived in a large representative sample. Here, we aim to optimize MAPS-EASI for routine pediatric care via psychometric validation of the MAPS-EASI 2.0 Irritability Screener and Impact Rating. Data on 2-5-year-old children (N=1,508) were utilized to derive generalizable thresholds for MAPS-EASI 2.0. Analyses were guided by timing of toddler (<i>n</i>=463) and preschool (<i>n</i>=1045) age well-child visits, generating two Irritability Screener forms: (<b>1</b>) 3 items for toddlers (18-33 months); and (<b>2</b>) 4 items for preschoolers (34-66 months). Irritability Screener severity cut-points were established with good-to-excellent classification (areas under the curve=0.84, 0.88), sensitivity (0.83, 0.82), and specificity (0.72, 0.79), for toddlers and preschoolers respectively. Over-identification was reduced by including impairment in the screening algorithm via the MAPS-EASI 2.0 Impact Rating. The clinical threshold for this integrative algorithm identified 15% and 18% of toddlers and preschoolers, respectively; these rates align with established population prevalence. Pragmatic, transdiagnostic developmental screening tools for routine care may accelerate real-world impact of irritability science for early mental health.