Using the Rasch Model to Develop a Measure of Participation Capturing the Full Range of Participation Characteristics for the Patients with Hand Injuries.

The purpose of this paper was to report on the first step in the development of a new instrument to measure participation including the full range of its characteristics.  The 30-item participation behavior questionnaire (PBQ) was developed from four main sources (a literature review of the theatrical basis of participation, available participation measures, and interviews with patients and experts about participation). Item selection and the reliability and validity of the measure were explored using Rasch measurement modeling for analysis.  A total of 404 individuals referred to rehabilitation after hand, wrist, or upper extremity surgery to reduce impairment from trauma, at least 2 months post-injury.  An initial pool of 100 items; reflecting 14 characteristics of participation was initially reduced to 91 items after review by 15 participation experts and then further reduced to 30 items by three rounds of Rasch analysis removing misfitting items. The final PBQ has a person reliability of 0.91 with separation of 3.22, indicating it can reliably differentiate four levels of participation. There are no misfitting items and the instrument is unidimensional. All 14 characteristics of participation were retained in the PBQ, and none of the 30 items refer specifically to upper extremity issues.  The 30 participation behavior items of the PBQ show promise of being a psychometrically sound measure of participation. Further research is needed to validate the PBQ in samples of people with a range of other disabilities.