DSM-5-TR Severity Levels for Autism Spectrum Disorder (ASD): Agreement Between Clinicians Using Telehealth and In-Person Assessment Procedures.

The DSM-5/DSM-5-TR includes clinician-reported severity levels to help individualize autism spectrum disorder (ASD) diagnoses. Severity levels for the two core autism domains of social communication and interaction (SCI) and restricted and repetitive behaviors (RRBs) are assigned using a 3-point Likert scale, with higher levels indicating greater symptom severity. Research examining the consistency of DSM-5-TR severity-rating agreement has been limited. Four doctoral-level clinicians independently evaluated 49 toddlers, ages 16-31 months, with each child receiving both a telehealth and an in-person (IPA) comprehensive diagnostic assessment. Previous research using this cohort demonstrated high agreement between clinicians for overall ASD diagnostic outcome. The present study examined agreement in clinician-assigned DSM-5-TR severity levels. Agreement between assessment protocols was fair for SCI (κ = 0.318, 95% CI [-0.114, 0.352]) and slight for RRB (κ = 0.195, 95% CI [-0.046, 0.436]). Further analyses revealed no significant differences in severity ratings based on individual clinician, clinical team, or assessment protocol. These findings suggest that factors beyond the core ASD symptom domains may influence clinicians' assignment of DSM-5-TR severity levels despite guidance that ratings should reflect impairment within SCI and RRB. The relatively low agreement observed for severity ratings, despite previously demonstrated high agreement for ASD diagnostic classification, suggests that assigning a diagnosis and determining the level of support needed represent distinct clinical decisions. Improving the consistency and transparency of DSM-5-TR severity level assignment may strengthen clinical communication, treatment planning, and equitable access to services while enhancing the reliability and clinical utility of these specifiers across diagnostic settings.