Measurement Properties of the Michigan Hand Outcomes Questionnaire in Patients With a Metacarpal or Phalangeal...

The Michigan Hand Outcomes Questionnaire (MHQ) is among the most frequently used patient-reported outcome measures to evaluate hand disorder-specific outcomes. However, despite its frequent use in patients with hand trauma, its measurement properties have mainly been evaluated in nontraumatic hand conditions. Consequently, although the MHQ is often described as a validated questionnaire, its measurement properties in patients with acute hand trauma remain unclear. In addition, the MHQ is frequently summarized as a single overall score derived from the 6 domains, often interpreted as representing "hand function." However, it is unclear whether combining these domains into a single score is appropriate.

Three months postinjury data of the MHQ from 442 adult patients with metacarpal and phalangeal fractures were analyzed. Structural validity was evaluated using exploratory and confirmatory factor analysis. Construct validity was assessed through known-group comparisons based on a priori hypotheses. Internal consistency was evaluated using Cronbach alpha.

Exploratory factor analysis identified 6 factors corresponding to the original MHQ domains. Confirmatory factor analysis showed poor fit for a unidimensional model. In contrast, the 6-factor model showed better fit. Known-group comparisons confirmed 83% of the hypotheses. Domain scores showed clearer differences between clinical subgroups than the overall score. Internal consistency ranged from 0.79 to 0.95 across domains.

The MHQ demonstrated sufficient construct validity and internal consistency for its continued use as a 6-domain instrument in patients with metacarpal and phalangeal fractures. We recommend reporting the individual domain scores, as a summarized overall score may mask clinically relevant differences between domains.