Assessment of the Lequesne index of severity for osteoarthritis of the hip in an elderly population.
Dawson J., Linsell L., Doll H., Zondervan K., Rose P., Carr A., Randall T., Fitzpatrick R.
OBJECTIVE: To assess the measurement properties of the Lequesne index of severity for osteoarthritis of the hip (LISOH) together with its overall usefulness with reference to the original stated aims. METHOD: Postal questionnaire was sent to a random sample of 5500 Oxfordshire residents, aged 65 and above. Respondents with hip symptoms at baseline (but without verification of a diagnosis) were sent an identical follow-up questionnaire 12 months later. The questionnaire included a general health section, including the Short Form-36 survey, and a hip section which began with a screening question about hip pain. Respondents who reported having a prolonged episode of hip pain were asked to complete the LISOH. RESULTS: At baseline, response rate of 66.3% (3341/5039) was obtained from eligible participants; 19.2% (610/3175) of respondents reported having hip pain. Internal reliability (Cronbach's alpha) was 0.84 (95% CI: 0.81-0.86) for all 11 items of the LISOH; however, factor analysis identified two factors (sub-scales): "function and mobility" and "pain and discomfort". Rasch analysis revealed that the two factors were only unidimensional when applied to sub-groups of respondents. Convergent validity of the LISOH was questionable, as the "function and mobility" factor was more highly correlated with SF-36 bodily pain score than was the "pain and discomfort" factor. The assessment of sensitivity over time was problematic due to changing patterns of symptomatic weight-bearing joints over time. CONCLUSIONS: The current study identifies major limitations with the LISOH--particularly if used as a single composite measure.