Overall Assessment of the Speaker's Experience of Stuttering (OASES™)

Measure the impact of stuttering with this quick, easy-to-use, comprehensive tool. Evidence-based and founded upon a solid theoretical framework, the OASES protocol supports clinical and research decision-making. OASES Impact Scores and Impact Ratings help you provide diagnoses, qualify individuals for therapy, justify third-party payment, document improvement, and evaluate treatment efficacy. OASES materials are available for use in the USA, for use outside the USA, and for Research Purposes.

Uses & Applications

Content & Administration

Each question is scored on a 5-point Likert scale. Responses are totaled into Impact Scores and Impact Ratings (Mild through Severe). Scoring can be completed for the entire test, as well as for each of the four sections individually. These sections examine:

OASES Age Groups

OASES Response Forms have been developed and validated, with age-appropriate items and instructions for 3 age groups:


OASES Response Forms have been translated into numerous languages. To discuss the process of translating the OASES Response Forms or Technical/Scoring Manual to your own language, please email Info@StutteringTherapyResources.com.

Clinical and Research Licenses

Researchers and clinicians who wish to adapt the OASES for specific situations may purchase a Clinical or Research license. Email Info@StutteringTherapyResources.com for more information.

Features & Benefits

Psychometric Data and Validation

Frequently Asked Questions

What is the OASES for? The OASES provides a comprehensive assessment of the stuttering disorder from the speaker’s perspective. It gives clinicians and researchers meaningful insights into the client’s experiences that can be used in the diagnostic process, for treatment planning, and in outcomes assessment. 

What information does the OASES give me? The OASES gives clinicians and researchers an impact rating and impact score, which reflect the degree of adverse impact a speaker experiences due to stuttering. The impact score combines information about (a) the speaker’s perceptions about stuttering; (b) the negative affective (feelings), behavioral (actions), and cognitive (thoughts) reactions that the speaker has to stuttering; (c) the functional communication difficulties a speaker may have in different speaking environments; and (d) the impact of stuttering on the speaker’s overall quality of life. The OASES is the only published tool that specifically examines Quality of Life in people who stutter. It is also the only tool that establishes the degree of adverse impact when qualifying a child who stutters for therapy in a school setting.

How long does it take to administer the OASES? Regardless of the version (OASES-S, OASES-T, or OASES-A), the OASES typically takes 15 to 20 minutes for speakers complete. Scoring requires only 5 minutes.

When do I use the OASES? Clinicians and researchers can use the OASES:

Who can use the OASES? The OASES can be used by speech-language pathologists, research scientists, and others (e.g., psychologists) who work clinically or do research with individuals who stutter.

How was the OASES developed? The OASES was developed through an iterative process that involved input from people who stutter, speech-language pathologists who specialize in stuttering, members of the stuttering community, and others who interact with children and adults who stutter (e.g., parents and teachers). An initial set of questions was identified through focus group discussions and expert review panels. These questions were then tested through several pilot studies, each of which resulted in refinements to the wording of the questions, the terms used in the descriptions, and the scoring procedures. The OASES-A for adults was developed first, and reliability and validity were established through a study published in the Journal of Fluency Disorders (Yaruss & Quesal, 2006). The tool was then adapted for the needs of school-age children (OASES-S) and teens (OASES-T). In each case, pilot data were carefully scrutinized to ensure readability, reliability, and validity for assessing key aspects of the speaker’s experience of stuttering.

How do I interpret OASES findings? The OASES yields a score on a 5-point scale that indicates the amount of adverse impact a person experiences due to stuttering. Higher scores indicate higher levels of negative impact. Impact ratings reflect mild, mild-to-moderate, moderate, moderate-to-severe, and severe adverse impact. Scores can be interpreted for the test as a whole and for each of four sections separately. Clinicians can also examine a speaker’s response for  individual items to identify specific challenges to address in therapy. The manual includes a detailed set of interpretation guides, which help clinicians compare their clients’ experiences to patterns commonly seen in the experiences of other people who stutter.

How will the OASES help me in my daily work with people who stutter? Many clinicians report that they are not certain where to start when working with people who stutter. The detailed results from the OASES can provided exactly that starting point by highlighting for clinicians (and for speakers) what aspects of life are most affected by stuttering. For example, responses on the OASES can indicate whether a speaker would benefit from therapy for reducing negative reactions to stuttering, or whether stuttering is causing the speaker to avoid words or speaking situations. Results can also reveal which types of situations are hardest for speakers and provide insights into how those difficulties can be overcome. Clinicians who use the OASES routinely use their clients’ responses to individual test items as a starting place for discussions about sensitive topics in therapy that they might otherwise have difficulty bringing up. For this reason, the OASES can be used both during the evaluation and on a daily basis in therapy to support the client in identifying goals for therapy and assessing whether positive changes have occurred. The OASES differs from the Stuttering Severity Instrument (Riley, 2009) and other measures of stuttering behavior in that the OASES provides information about the speaker’s experience of stuttering, not the listener’s or clinician’s experience. Thus, the OASES provides insights into what people who stutter think or feel about their stuttering, how much difficulty they experience in key situations, and the degree to which stuttering affects their lives as a whole. The SSI (or other measure of surface stuttering behaviors) and the OASES can be used together to provide a more complete picture of the impact of stuttering. Because it is based on the speaker’s daily life, the OASES provides information that goes well beyond that available through typical severity ratings.