A comparison of measures of health status in rheumatoid arthritis.
Fitzpatrick R., Newman S., Lamb R., Shipley M.
One hundred and five patients with rheumatoid arthritis were assessed on two occasions separated by 15 months, by means of the ARA functional scale, the Mallya and Mace index, the Health Assessment Questionnaire (HAQ) and the Functional Limitations Profile (FLP). Thirty three per cent of patients were assessed as clinically changed in terms of the ARA scale. On both occasions cross-sectional correlations were strongest between the health status measures (HAQ and FLP) and grip strength and the Ritchie articular index. The sensitivity and specificity of the two health status measures in relation to clinical change were calculated and overall the HAQ and FLP achieved similarly modest levels of sensitivity and specificity. The greater amount of precision and information provided by the FLP has to be weighed against the simpler measurement assumptions and shorter time required to administer the HAQ.