OBJECTIVES: Ox-PAQ was developed to be FDA compliant, is a 23-item generic PRO measure that is theoretically grounded in the ICF. It comprises three domains, Routine Activities, Emotional Well-Being and Social Engagement. Initial analyses indicate that the measure is valid, reliable and sensitive to change in a group of neurological conditions. Aim of this study was to make an assessment of the sensitivity to change of the OX-PAQ exclusively in people with Parkinson’s (PwP).

METHODS: PwP were recruited and completed the Ox-PAQ electronically on two occasions, six months apart. Participants completed an additional four questions during the second administration of the Ox-PAQ to assess any relevant changes since baseline completion. For each Ox-PAQ domain, the minimally important difference (MID) and effect size (ES) was calculated from the participants who indicated small, but meaningful changes in health status.

RESULTS: Participants who completed the Ox-PAQ on both occasions and with no missing data for at least one Ox-PAQ domain were entered into the final analysis. This equated to 268 respondents (67.34%). In those indicating that their health status was ‘slightly worse’, for Routine Activities (n=67) a MID of 5.49 and an ES of 0.28 was calculated. For Social Engagement (n=73) the MID was 5.91 and the ES 0.29. For Emotional Well-Being (n=72) the MID was 4.92 and the ES 0.27. In those indicating ‘slightly better’, for Routine Activities (n=21) a MID of 2.91 and an ES of 0.16 was calculated. For Social Engagement (n=16) the MID was 1.90 and the ES 0.10. For Emotional Well-Being (n=20) the MID was 4.50 and the ES 0.27.

CONCLUSIONS: Data presented provides MID and effect sizes for Ox-PAQ domains that will act as guidance for those powering clinical trials assessing activity and participation in PwP. Ongoing research with alternative conditions will provide further sensitivity to change data for the Ox-PAQ.