Validating the Michigan Hand Outcomes Questionnaire in patients with rheumatoid arthritis using Rasch analysis.

After collapsing disordered thresholds and removing misfitting items, the MHQ demonstrated reliability and validity for assessing outcomes in patients with RA with metacarpophalangeal joint deformities. These results suggest that interpreting individual domain scores may provide more insight into a patient's condition rather than analyzing an overall MHQ summary score. However, more Rasch analyses are needed in other RA populations before making adjustments to the MHQ.