Reliability of patient and proxy reported pre-injury functional status in orthopaedic trauma: A prospective...

Patient-reported outcome measures (PROMs) are essential for evaluating functional recovery after orthopaedic trauma. However, obtaining accurate pre-injury baseline PROM scores is often infeasible due to the emergent nature of traumatic injuries. This study aimed to assess the reliability of retrospective patient- and proxy-reported pre-injury functional status over time.

This prospective observational study was conducted at a level I trauma center and included 173 adult patients presenting with acute upper or lower extremity fractures. Participants completed Patient-Reported Outcomes Measurement Information System Computer Adaptive Test (PROMIS CAT) surveys at week-0 (within 7 days of injury), week-2 and week-6 post-injury, all retrospectively recalling their pre-injury functional status. A subset of 91 patients also had designated proxies complete the same PROMIS surveys at the week-0 time point. Paired t-tests and Wilcoxon signed-rank tests evaluated score differences over time and between patients and proxies. Reliability was assessed using intraclass correlation coefficients (ICC), Bland-Altman plots and linear mixed-effects models adjusted for age, sex, comorbidities and baseline ambulatory status.

PROMIS scores remained consistent across the three time points, with minimal mean differences (e.g., lower extremity: week 0-6 difference = 0.2 ± 3.9, p = 0.66). ICCs demonstrated excellent within-patient reliability (lower extremity: 0.94; upper extremity: 0.96). Comparisons between patient and proxy reports also demonstrated high agreement, with small mean differences (lower extremity: 0.29 ± 3.7; upper extremity: -0.19 ± 2.5), and Bland-Altman plots revealed no systematic bias. Notably, a ceiling effect was observed in upper extremity PROMIS scores across all time points, limiting their variability.

Patients can reliably recall their pre-injury functional status up to 6 weeks following orthopaedic trauma, as there was little variation between week-0, week-2 and week-6 self-assessments. Additionally, proxy-reported scores provide highly concordant estimates of pre-injury function, making them a valid alternative when patients are unable to self-report. These findings support the use of retrospective PROM assessments in both clinical care and research to establish pre-injury baselines and track recovery in the orthopaedic trauma population.