Prevalence, stability, and predictive utility of the Multidimensional Assessment of Preschoolers Study clinically optimized irritability score: Pragmatic early assessment of mental disorder risk.

Clinically significant early childhood irritability prevalence is akin to the pediatric obesity epidemic and may warrant similar universal screening/intervention. Also, irritability's stability demonstrates the common guidance "they'll grow out of it" to be false. Finally, pragmatic irritability assessment has transdiagnostic predictive power and addresses a need for feasible measures to flag risk.