The Prosthetic Mobility Questionnaire, a tool for assessing mobility in people with lower-limb amputation: validation of PMQ 2.0 in Slovenia.

The aim of this study was to examine the metric properties of the Prosthetic Mobility Questionnaire, an outcome measure of mobility following lower-limb amputation, in Slovene outpatients undergoing rehabilitation. The 12-item Prosthetic Mobility Questionnaire was administered to 148 Slovene adults (74% men) with unilateral lower-limb amputation since >12 months and regularly wearing a prosthesis. The psychometric analysis included classical test theory methods and Rasch models. Rasch analysis disclosed two pairs of locally dependent items (same task but in opposite directions: walk up/down stairs; walk up/down a hill). Thus, we devised a new version (PMQ 2.0) assessing all 12 Prosthetic Mobility Questionnaire items but calculating the global score on only 10, i.e. considering-for each pair of locally dependent items-just the item with worst performance. The PMQ 2.0 demonstrated correct functioning of rating scale categories, construct validity (item fit, hierarchy of item difficulties), convergent validity, high-reliability indices and unidimensionality. In conclusion, the new 10-item PMQ 2.0 shows good reliability and validity, and an excellent overall metric quality for measuring perceived mobility capabilities in people with lower-limb amputation.