METHODS: The OASES-A-J was administered to 200 adults who stutter in Japan. All respondents also evaluated their own speech (SA scale), satisfaction of their own speech (SS scale) and the Japanese translation version of the Modified Erickson Communication Attitude scale (S-24). The test-retest reliability and internal consistency of the OASES-A-J were assessed. To examine the concurrent validity of the questionnaire, Pearson correlation was conducted between the OASES-A-J Impact score and the S-24 scale, SA scale and SS scale. In addition, Pearson correlation among the impact scores of each section and total were calculated to examine the construct validity.

RESULTS: The OASES-A-J showed a good test-retest reliability (r=0.81-0.95) and high internal consistency (α>0.80). Concurrent validity was moderate to high (0.55-0.75). Construct validity was confirmed by the relation between internal consistency in each section and correlation among sections' impact scores. Japanese adults showed higher negative impact for 'General Information', 'Reactions to Stuttering' and 'Quality of Life' sections.

METHOD: The participants ranged from 3 years 3 months to 4 years 9 months at the start of the study. Beyond-clinic speech samples were obtained at 1 month and 1 week pretreatment and immediately post-Stage 1, and at 1 month, 3 months, 6 months and 12 months post-Stage 1.

RESULTS: Two participants, who were bilingual, achieved near-zero levels of stuttering at 12 months posttreatment. Near zero levels of stuttering were also present in their untreated languages. One participant withdrew due to reasons not connected with the research or treatment. The remaining participant, who presented with severe stuttering, completed Stage 1 but had some relapse in Stage 2 and demonstrated mild stuttering 12 months post-Stage 1.