Participation is a key concept in the International Classification of Functioning, Disability, and Health and a central rehabilitation outcome, but agreement on measuring participation is lacking. Participation Assessed with Recombined Tools–Objective (PART-O) was developed for traumatic brain injury (TBI), used in the TBI Model Systems, and endorsed as a common data element. However, the content of PART-O is not unique to TBI and the instrument may be applicable to other populations. The aim of this research is to determine the psychometric properties of PART-O in people with spinal cord injury (SCI).

The PART-O items were administered to 468 people with SCI from 4 months to 40 years post injury along with the most frequently used measure of participation in SCI: the Craig Handicap Assessment and Reporting Technique (CHART). The PART-O was administered a second time, 2–4 weeks later to assess test-retest reliability. Rasch analysis was used to ensure a unidimensional linear measure and evaluate the psychometric properties of PART-O in SCI.

To achieve unidimensionality and maintain ordered steps within item categories, 3 competing items (hours per week spent working, in school, and homemaking) were summed into a testlet, and infrequently endorsed categories were combined. The resulting measure was unidimensional (first contrast less than 2.00) with all items fitting well (no infit or outfit above 1.40 and no disordered categories in any item), and acceptable person separation (2.00) and reliability (0.80). PART-O had a normal distribution with no ceiling or floor effects. The test-retest reliability was 0.97 and the correlation between PART-O and CHART was 0.79.

The PART-O shows promise for expanding its use into SCI. It is highly correlated with the legacy CHART instrument, and it has advantages over CHART, of being a normally distributed linear measure without ceiling effects.