Further Validation of the Patient/Parent-Reported Outcome Measure of Fracture Healing (Proof-Le) Questionnaire for Lower Extremity Fractures in Children

Clinical trials of pediatric fractures seldom show differences based on patient-reported outcome measures (PROMs), possibly because the PROMs do not adequately capture patients’/parents’ perspectives about outcomes that matter. The Patient Reported Outcomes of Fracture Healing (PROOF) questionnaires are a new set of PROMs designed specifically for children's fractures. Derived from parents and patients, the PROOF includes 4 domains (Scores:0-100): “How it Looks’; “How it Feels”; “How it Works”; and “How it Healed”, which captures the overall recovery experience. This project evaluates the reliability, validity and responsiveness of the PROOF-LE for lower extremity fractures in children. Children with lower extremity fractures were prospectively enrolled. Parents and children (> 8yrs) completed the parent & child versions of the PROOF-LE respectively, at 3 time-points from treatment until full recovery. Test-retest reliability (2-weeks apart) was determined at final healing using intraclass correlation coefficient (ICC); and internal consistency using Cronbach's Alpha. Convergent validity was assessed comparing the total and domain scores of the PROOF-LE to realted domains of the PODCI using Pearson correlation. Construct validity was evaluated by comparing fractures with and without complications. Responsiveness (sensitivity to change) was evaluated over 3 time-points using standardized response means (SRM). Finally, parents’ scores were compared with their respective children's scores, using paired t-test and Pearson correlation. 335 children's [197 boys/138 girls; mean age (SD): 9.9yrs (4.4)] fractures of the pelvis/hip (4), femur (99), knee (24), tibia (141), ankle (40) and foot (27) were included. The PROOF-LE demonstrated moderate to excellent test-retest reliability for the Total and domain scores for children (ICC:0.75 - 0.89) and parents (ICC:0.69-0.88); high internal consistency for children (0.72 - 0.9) and parents (0.72 - 0.91). PROOF-LE domain scores correlated positively with like domains of the PODCI. As hypothesized, fractures with complications scored significantly worse than those without. The PROOF-LE was highly responsive with SRMs of 0.99 (parents) and 1.2 (children) for the total scores over three time-points. Parents’ scores correlated strongly with their children (r=0.89; p < 0 .001) with parents’ scores an average of 2.9 points lower than children's. The PROOF-LE is the only PROM designed specifically to measure outcomes of pediatric lower extremity fractures and their treatments. The child and parent versions of the PROOF-LE are reliable, internally consistent, valid and responsive for lower extremity fractures in children. The PROOF-LE reports scores across four different domains and in total, which allows it to better distinguish pros and cons of competing treatments, information about which will inform future decision-making about treatment choices. The PROOF-LE may be considered as the PROM of choice for pediatric lower extremity fractures and their treatments.