The Apraxia of Speech Rating Scale: Reliability, Validity, and Utility

Area of Science:

• Speech-Language Pathology
• Neurogenic Communication Disorders
• Clinical Assessment Tools

Background:

• Apraxia of speech (AOS) is a motor speech disorder affecting speech planning and programming.
• Accurate assessment is crucial for diagnosis and treatment planning in neurogenic communication disorders.

Purpose of the Study:

• To evaluate the interrater reliability and validity of the Apraxia of Speech Rating Scale (ASRS-3.5).
• To determine the scale's effectiveness in indexing AOS presence, severity, and key features.

Main Methods:

• Interrater reliability assessed with 27 participants.
• Validity examined in 308 participants (120 with AOS, 188 without) using item analysis and correlation with independent clinical ratings.
• Regression models used to predict AOS presence.

Main Results:

• The ASRS-3.5 demonstrated good to excellent interrater reliability for individual items and excellent reliability for the total score.
• The scale effectively differentiated between participants with and without AOS.
• Total scores below 7 and above 10 showed excellent diagnostic sensitivity and specificity for AOS.

Conclusions:

• The ASRS-3.5 is a reliable and valid instrument for assessing AOS presence, severity, and features.
• The scale exhibits high sensitivity and specificity, distinguishing AOS from aphasia and dysarthria in neurodegenerative conditions.