Development and validation of a patient-centered outcome measure for young adults with pediatric hip conditions: the "Quality of Life, Concerns and Impact Measure".

To develop and validate a patient-centered, evaluative outcome measure to assess patient-significant and identified impacts of the three pediatric hip conditions (the "Quality of Life, Concerns and Impact Measure" (QoLC&I)), for use by patients and clinicians in discussions over treatment options and the evaluation of treatment and post-operative rehabilitation. The measure was developed through a qualitative study, via two web-based forums (patient narratives, n=84) and one specialist orthopedic adult hip clinic (conducting interviews, n=38). The draft (1) measure was piloted in an asynchronous web-based discussion group forum; following revision, it was piloted with a group of clinicians and patients to assess its patient and clinical utility, face and content validity. The final, refined prototype measure (QoLC&I, draft 3) was subjected to psychometric evaluation. A total of 230 patients provided useable data for the psychometric analysis: 70% (160) had a confirmed diagnosis of Developmental Dysplasia of the Hip, 15% (35) Perthes, 11% (26) Slipped Upper Femoral Epiphyses; 4% (9) PHC not stated. The scale showed good acceptability (few missing items, good spread, low floor/ceiling effects), relevance (76% stating they would find the measure useful in their discussions with clinicians), and good internal consistency (Cronbach's α=0.98; average ICC=0.98). Hypotheses on convergent validity (with the General Health Questionnaire, to measure depression, and the International Hip Outcome Tool Short Form, to measure quality of life) and divergent validity (with the General Self-Efficacy Scale, to measure coping) were confirmed. The 64-item QoL&CI measure is a practical and valid measure addressing areas of clinical and patient significance and has potential value to assist patients and clinicians in discussions about treatment choices and treatment progress. Future research will address further psychometric testing (test-retest validity and responsiveness to change), in additional sites, and embedding the measure into clinical practice.