The Hong Kong Chinese version of the Jebsen Hand Function Test: Inter-rater and test-retest reliabilities

Objectives: To investigate the inter-rater and test-retest reliability of the Hong Kong Chinese version of the Jebsen Hand Function Test (JHFT-HK); to evaluate the discriminative power of the JHFT between patients with rheumatoid arthritis (RA) and people free from the disease; and to investigate the relationship between the JHFT scores and the performance of grip and pinch strengths. Methods: Twenty-four female subjects with RA and 28 healthy females matched for age and occupation were recruited by convenience sampling for testing of their hand function using the JHFT-HK. The relationship between JHFT-HK scores and grip and pinch strengths were also examined. Results: The intraclass correlation coefficients (ICCs) of inter-rater reliability (0.70-0.98) and test-retest reliability (0.68-0.98) of the JHFT-HK were shown to be satisfactory. Independent t test revealed significant differences between the two groups in all subtests except for the writing test (p < 0.05), reconfirming that the JHFT-HK is a valid assessment tool for distinguishing between subjects with and without RA. Independent t test also revealed that subjects without RA in the Hong Kong community performed significantly faster in most of the subtests of the JHFT-HK (p < 0.05) when compared to the corresponding time scores established by Jebsen, Taylor, Trieschmann et al. (1969) in the same group of subjects. Hence, comparing their normative data with the data from our RA subjects might result in overestimation of the hand function of our local subjects who actually have more limited hand function. In addition, there is only fair-to-moderate correlation between power grip, pinch grip strength and hand function as represented by the JHFT-HK. Conclusion: Simply assessing grip and pinch strength is not sufficient to represent the hand function abilities of an individual. It is suggested that the JHFT-HK is a useful and standardized test for reflecting the dynamic hand function of patients with RA.