Prospective multicentre validation study of a new standardised version of the 400-point hand assessment

BACKGROUND: Hand rehabilitation needs valid evaluation tools; the 400-point Hand Assessment (HA) is an exhaustive but not standardised tool. The aim of this study was to validate a standardised version of this test. METHODS: A modified version and a standardised prototype was made for this prospective validation study (four centres, three countries). Psychometric properties studied: reliability (intra-rater and inter-rater, standard error of measurement [SEM], minimum detectable change [MDC],internal consistency); content validity, construct validity with Jebsen Taylor hand function test, QuickDASH, MOS-SF 36 and pain; responsiveness, using an anchor-based approach (ROC curve with area under curve, mean response change) with calculation of MCID. For SEM, MDC and responsiveness, QuickDASH was used for comparison. RESULTS: One hundred and seventy-six patients with hand/wrist injuries were included between May 2013 and February 2015. One hundred and seventy were available for final analysis: 67% men; mean age 43.4 ± 13.2 years; both manual and office workers (46, 5% of each); 37% had a hand or wrist fracture. Reliability: ICC intra-rater = 0.967 [0.938–0.982]; inter-rater = 0.868 [0.754–0.932]. Distribution-based approach: for 400-point HA/QuickDASH: SEM = 3.48/4.52, MDC = 9.065/12.53, internal consistency of 400-point HA: Cronbach α = 0.886. Validity: Content validity was good according to COSMIN guidelines. Construct validity: correlation coefficient: Jebsen-Taylor hand function test = − 0.573 [− 0.666–0.464], QuickDASH = − 0.432 at T0 [− 0.545–0.303], − 0.551 at T3 [− 0.648–0.436]; MOS-SF 36 physical component = 0.395 [0.263–0.513]; no correlation with MOS-SF 36 mental component = 0.142 [− 0.009 + 0.286] and pain = − 0.166 [− 0.306 + 0.018]. Responsiveness: Anchor-based approach: AUC Δ400-point HA = 0.666 [0.583–0.749], AUC ΔQuickDASH = 0.556 [0.466–0.646]. MCID (optimal ROC curve cut-off): 6.07 for 400-point HA, − 2.27 for QuickDASH. MCID with mean response change + 12.034 ± 9.067 for 400-point HA and − 8.03 ± –9.7 for QuickDASH. The patient’s global impression of change was only correlated with the Δ400-point HA. CONCLUSIONS: The 400-point HA standardised version has good psychometric properties. For responsiveness, we propose an MCID of at least 12.3/100. However, these results must be confirmed in other populations and pathologies. TRIAL REGISTRATION: This study was retrospectively registered into ISCTRN registry (Number ISRCTN25874481) the 07/02/2019.