Defining Stimulability for Voice-Specialized Speech Language Pathologists: A Scoping Review

PurposeSpeech-language pathologists have used the term "stimulability" since at least the 1950s (Milisen, 1954). However, the term is used in multiple ways in the current literature, and authors frequently do not make the distinction between stimulability testing (i.e., the procedure) and stimulability level (i.e., the results of the procedure). This paper presents a narrative overview of the history of stimulability testing in voice disorders, proposes a new standard definition for stimulability testing, and provides a scoping review of the terminology, definitions, behavioral targets, and types of measurement scales used to describe stimulability testing and stimulability level in the current literature. MethodsA literature search was conducted in PubMed, EBSCOhost, and Google Scholar for peer-reviewed articles containing the terms "stimulability" or "stimulable". Articles including information regarding the behavioral assessment of patients with voice disorders were included. Results93 articles were included in the review. Only 23% of articles provided an adequate definition of stimulability testing or stimulability level; over half (51%) mentioned search terminology in passing without any further definition or description, and the remaining quarter (26%) described stimulability testing or level rather than providing a formal definition. The term "stimulability" in isolation was used to refer to stimulability testing in 13% of instances and stimulability level in 51% of instances. ConclusionStimulability testing and stimulability level are infrequently defined and poorly differentiated from each other in the current literature. Given the clinical importance of stimulability testing, increased care is needed in future work to be specific and precise with terminology.