Development and validation of a research version of the Overall Assessment of the Speaker's Experience of Stuttering- Adult (OASES-A-R).

Background: The Overall Assessment of the Speaker's Experience of Stuttering for Adults (OASES-A; Yaruss & Quesal, 2016) is a widely used measurement tool designed to evaluate the adverse impact associated with stuttering. Items examine general perceptions of stuttering, personal reactions to stuttering, functional communication difficulties, and consequences for quality of life. This paper presents a shortened research version of the OASES-A response form (OASES-A-R) that can be used by researchers in scientific studies involving adults who stutter that reflect the Section and Total Scores of the original OASES-A using fewer items.

Method: Previously collected OASES-A data (N = 315) were analyzed via graded response modeling to identify discrimination values of each OASES-A item in measuring each OASES-A Section Total Score. Items with the highest discrimination and items judged by expert clinicians to be more important in measuring adverse impact (N = 27) were used to create a shortened OASES-A-R. The shortened OASES-A-R response form was then validated and compared to the full OASES-A response form in an independent sample (N = 156).

Results: The shortened 25-item OASES-A-R response form demonstrated very high and positive correlations with the full OASES-A response form. Similarly, each OASES-A-R Section demonstrated high internal reliability coefficients similar to those of the OASES-A.

Discussion: The resulting 25-item OASES-A-R response form provides a reflection of the speaker's experience of stuttering as measured by the original 100-item OASES-A that is suitable for use in certain research studies of adults who stutter. Clinical use is not recommended, as the full OASES-A provides additional insights about a client's experience of stuttering that are necessary for effective treatment planning and intervention.