Editorial: The EDI-YC: A New Measure of Emotion Dysregulation in Young Children.

Although emotion dysregulation is at a peak during the preschool age (2-5 years) and clinically significant dysregulation has impact across the lifespan, there are surprisingly few ways to measure it in this age group. This is especially true for groups of children in whom emotion may be particularly dysregulated, such as those with autism spectrum disorder. The modern, rigorous development of a well-grounded measure has profound clinical implications. Practically, it gives a common reference for the severity of a clinical issue, which is the foundation of measurement-based care and quantitative research. Theoretically, the process also defines the issue involving the scale designers, those whom the scale is about, and even the scale users as the measure is used and refined over years. Measures of preschool emotion dysregulation will allow us to better map its trajectory from preschool throughout the lifespan. In this issue, Day and Mazefsky et al. rigorously extend the Emotion Dysregulation Inventory (EDI; a set of questionnaires) to 2 groups of preschoolers, those representing children with neurodevelopmental issues, especially autism, and those without.