Iranian Rehabilitation Journal (Sep 2024)
Investigating the Development and Evaluation of the Psychometric Properties of the Stuttering Related Quality of Life Questionnaire
Abstract
Objectives: People who stutter (PWS) experience many problems in their lives in addition to speech fluency disorder. Meanwhile, stuttering reduces their quality of life (QoL). QoL depends on different social, economic, and cultural conditions of societies. Considering that there is no specific questionnaire to investigate the QoL in Iranian PWS; this study develops and evaluates the psychometric properties of a stuttering related QoL questionnaire (SRQoLQ). Methods: First, by interviewing 11 PWS, with the help of 10 speech-language pathologists in the stuttering field, in addition to reviewing the literature, initial items were developed and a preliminary version of the SRQoLQ was designed. The content validity of the SRQoLQ was evaluated using two qualitative and quantitative methods (determining content validity ratio and content validity index) using the opinions of 12 experts. The qualitative method was also used to determine the face validity and interviews were conducted with 10 PWS. Finally, the reliability of the SRQoLQ was investigated through internal consistency and test re-test reliability with the participation of 83 and 30 PWS, respectively. Results: Interviews with PWS and experts in addition to literature review led to the development of a questionnaire with 40 items. After determining content and face validity, the number of items in the SRQoLQ was reduced to 32. The results of calculating the Cronbach α coefficient showed the appropriate reliability of the SRQoLQ (0.96). The intraclass correlation coefficient of the SRQoLQ items in the test re-test phase ranged from 0.6 to 0.95. Moreover, the intraclass correlation coefficient value of the SRQoLQ was 0.95. Discussion: A suitable tool was developed to evaluate the QoL of PWS, and its psychometric properties were investigated. Based on the results, the SRQoLQ for PWS is a valid and reliable tool with 32 items that can be used for clinical or research purposes in the field of stuttering.