Sex and age differences in the patient-reported outcome measures and adherence to an osteoarthritis digital self-management intervention

To explore sex and age differences in Patient-Reported Outcomes Measures (PROMs) and adherence to digital osteoarthritis (OA) self-management intervention. A register-based study with data from an OA digital self-management intervention. PROMs and adherence were collected at baseline and/or 3 ​month follow-up: ‘pain intensity’ in hip/knee (best/worst: 0–10), ‘activity impairments' (best/worst: 0–10), ‘overall health’ perception (worst/best: 0–10), ‘physical function’ (30-s chair stand test), ‘health-related quality of life’ (EQ-5D-5L index score; worst/best: 0.243–0.976), the subscales and total scores of the Knee Injury/Hip Disability and Osteoarthritis Outcome Score (KOOS/HOOS-12; worst/best: 0–100), ‘fear of movement’ (yes/no), ‘walking difficulties' (yes/no), ‘programme adherence’ (0–100 ​% and ≥80 ​% [yes/no]), ‘patient acceptable symptom state’ (PASS; yes/no), and ‘treatment failure’ (those who answered no to PASS question and thought the treatment failed [yes/no]). We used linear/logistic regression to calculate mean/risk differences in the PROMs and adherence levels among sex and age groups at 3-month follow-up. We employed entropy balancing to explore the contributions of baseline characteristics and different covariates to the sex/age differences. We included 14,610 participants (mean (SD) age: 64.1 (9.1), 75.5 ​% females). Females generally reported better outcomes than males. Participants aged ≥70 had greater activity impairments, lower KOOS/HOOS-pain/function scores, more walking difficulties, less fear of movement and higher adherence than those