Relationships between psychosocial aspects of stuttering and self-disclosure of stuttering in a Japanese sample

Purpose: We aimed to psychometrically evaluate a Japanese version of the Disclosure of Stuttering Scale, from Boyle et al. (2018), and identify the psychosocial factors associated with level of stuttering self-disclosure among adults who stutter. Methods: Adults who stutter were recruited via stuttering self-help groups in Japan and the authors' contacts. Participants completed their demographics, the Disclosure of Stuttering Scale and other psychological scales assessing affective, cognitive, and social aspects of stuttering via an online survey. We analyzed 180 participants after those with unreliable or duplicate responses were excluded. The scale's reliability and validity were confirmed, and multiple linear regression analysis was conducted to predict the score of the Disclosure of Stuttering Scale using demographic variables and psychological measures. Results: The Japanese Disclosure of Stuttering Scale had good internal consistency (omega =.832) and test-retest reliability (intraclass correlation coefficient =.808), with no obvious ceiling or floor effects. Level of self-disclosure of stuttering was lower in the Japanese sample than in the United States sample (Cohen's d = 0.55) reported by Boyle et al. (2018). The regression model revealed that self-reported male gender, self-help group experience, higher self-acceptance, and lower selfstigma were associated with a higher self-disclosure level (adjusted R2 =.347). Conclusion: Our study indicated that self-reported gender and psychological and social (self-help experience) components were associated with the level of self-disclosure of stuttering. Furthermore, Japanese adults who stutter tended to report lower levels of self-disclosure compared to previous samples, which may reflect sociocultural differences.