Objectively-assessed outcome measures: a translation and cross-cultural adaptation procedure applied to the Chedoke McMaster Arm and Hand Activity Inventory (CAHAI)

Background: Standardised translation and cross-cultural adaptation (TCCA) procedures are vital to describe language translation, cultural adaptation, and to evaluate quality factors of transformed outcome measures. No TCCA procedure for objectively-assessed outcome (OAO) measures exists. Furthermore, no official German version of the Canadian Chedoke Arm and Hand Activity Inventory (CAHAI) is available. Methods: An eight-step for TCCA procedure for OAO was developed (TCCA-OAO) based on the existing TCCA procedure for patient-reported outcomes. The TCCA-OAO procedure was applied to develop a German version of the CAHAI (CAHAI-G). Inter-rater reliability of the CAHAI-G was determined through video rating of CAHAI-G. Validity evaluation of the CAHAI-G was assessed using the Chedoke-McMaster Stroke Assessment (CMSA). All ratings were performed by trained, independent raters. In a cross-sectional study, patients were tested within 31 hours after the initial CAHAI-G scoring, for their motor function level using the subscales for arm and hand of the CMSA. Inpatients and outpatients of the occupational therapy department who experienced a cerebrovascular accident or an intracerebral haemorrhage were included. Results: Performance of 23 patients (mean age 69.4, SD 12.9; six females; mean time since stroke onset: 1.5 years, SD 2.5 years) have been assessed. A high inter-rater reliability was calculated with ICCs for 4 CAHAI-G versions (13, 9, 8, 7 items) ranging between r = 0.96 and r = 0.99 (p < 0.001). Correlation between the CAHAI-G and CMSA subscales for hand and arm was r = 0.74 (p < 0.001) and r = 0.67 (p < 0.001) respectively. Internal consistency of the CAHAI-G for all four versions ranged between alpha = 0.974 and alpha = 0.979. Conclusions: The TCCA-OAO procedure was validated regarding its feasibility and applicability for objectively-assessed outcome measures. The resulting German CAHAI can be used as a valid and reliable assessment for bilateral upper limb performance in ADL in patients after stroke.