Refined Operational Definitions for the Apraxia of Speech Rating Scale.

Purpose: The Apraxia of Speech Rating Scale (ASRS; Strand et al., 2014) has quickly emerged as a standard for apraxia of speech (AOS) diagnosis in stroke despite mixed evidence. The purpose of this study was to analyze, clarify, and revise the scoring procedures and item definitions of the ASRS as a preliminary step for investigating the scale's psychometric properties in stroke.

Method: We evaluated the interpretation of the ASRS items and scale procedures by independently rating the video and audio examples provided with the latest dissemination of the ASRS. Discrepancies in ratings were discussed after each rating.

Results: Upon discussing the rating discrepancies, our team identified barriers to using the scale, including lack of clear operational definitions for the scale items, difficulties with applying the multidimensional rating scale, mismatch between the scale description and item description, and lack of detailed procedures for applying the scale. Based on this analysis, we developed a series of rules for scoring the ASRS in our own research applications with stroke survivors. We also clarified scale labels and operationalized definitions for most of the scale items.

Conclusions: Several potential concerns for reliable use of the ASRS were identified and addressed by clarifying the scale procedures and item definitions. We plan to use the updated procedures and definitions in research applications and are sharing them here for further input and potential applications from the research community. Research is needed to evaluate the impact of the changes on diagnostic classification and severity estimation for AOS.