Validity of outcome measures used to assess one and six month outcomes in orthopaedic trauma patients

Abstract

Introduction: To evaluate the validity of the 12-item Short Form Health Survey (SF-12), Sickness Impact Profile (SIP) and the Short Musculoskeletal Functional Assessment Questionnaire (SMFA) for use in an orthopaedic trauma population.

Materials and methods: A prospective validation trial was completed at a Level 1 adult trauma centre in Melbourne, Australia. One hundred and fifty four patients with orthopaedic trauma managed or followed-up by an orthopaedic unit were prospectively recruited. Patients with pathological fractures related to metastatic disease and/or an isolated orthopaedic injury, a documented history of mental illness or dementia or those for whom follow-up was likely to be difficult were excluded. The SF-12, SIP and SMFA were administered by a trained interviewer at one and six months. Each questionnaire was scored for the physical and mental components and then compared for content and construct validity at each time point.

Results: Complete data were collected for 134 patients at one and six months. The one and six month component scores correlated strongly between the SF-12 physical, SIP physical (r=0.513-0.669) and SMFA dysfunction (r=0.529-0.778); the SF-12 mental, SIP mental (r=0.643-0.719) and SMFA bother (r=0.564-0.602) components. The strength of association was greater for the six month time point compared to the one month measure. The SF-12 demonstrated no ceiling or floor effects, and provided a lower time burden on participants and researchers when compared to the SIP and SMFA.

Conclusions: For large population-based surveillance research into orthopaedic injury the SF-12 provides a valid and versatile tool.