Korean Version of the Confidence of Arm and Hand Movement Scale and Its Psychometric Properties.

Objective: To investigate the impact of self-efficacy in using one's upper limbs on the overall wellbeing of stroke patients, we developed the Korean version of the Confidence of Arm and Hand Movement (K-CAHM) scale by modifying the original CAHM to suit Korean cultural conditions.

Methods: This study was conducted from May 2022 to June 2023 at a rehabilitation hospital with 54 stroke patients. Participants with sufficient cognitive and verbal abilities were included, while those with severe comorbidities were excluded. For the translation and cultural adaptation of CAHM into Korean, permission was obtained from the original author. Two translators independently translated the questionnaire, followed by a consensus discussion and expert review to create K-CAHM version 1.0. After back-translation and further review, the final Korean version was completed. Reliability and validity were assessed using Cronbach's alpha, intraclass correlation coefficient (ICC), exploratory factor analysis, Bland-Altman analysis, and Pearson correlation.

Results: The K-CAHM showed good reliability (Cronbach's alpha=0.97; ICC=0.895). Bland-Altman plot analysis showed good agreement, indicating test-retest reliability. Moreover, K-CAHM showed good concurrent validity, demonstrated by its correlation with three domains of the International Classification of Functioning, Disability and Health: Fugl-Meyer assessment, the Jebsen-Taylor Hand Function Test, personal hygiene and bathing in the modified Barthel Index, and hand and stroke recovery domain in the Stroke Impact Scale.

Conclusion: The newly developed K-CAHM could complement other outcome measures, facilitating patient-centered rehabilitation in the Korean context.