Reliability and Validity Evidence of the STarT-Lower Extremity Screening Tool for Patients with Lower Extremity Fracture: A Prospective Study.

OBJECTIVES To determine whether a modified version of the STarT Back Screening Tool in its current structure has adequate properties for use in patients with lower extremity fracture. DESIGN Single center, prospective study. SETTING Level I Trauma Center. PARTICIPANTS Patients with lower extremity fracture without a history of chronic pain (N=114, 93% follow-up). INTERVENTIONS N/A MAIN OUTCOMES: Six-weeks after surgical fixation, subjects completed the STarT-Lower Extremity Screening Tool (STarT-LE), and a sub-sample completed the STarT-LE again one-week later. The following questionnaires were completed at six-weeks and six-months: Pain Catastrophizing Scale, Tampa Scale of Kinesiophobia, Brief Pain Inventory pain intensity subscale, and PROMIS Depression and Pain Interference computer adaptive testing modules. Reliability was evaluated with intraclass correlation coefficients (ICCs) and Cronbach's alpha (α). Convergent validity evidence was measured concurrently using Spearman's rho correlation between six-week STarT-LE and established questionnaires. Predictive validity evidence was evaluated by area under the curve analysis (AUC) using six-week STarT-LE total and psychosocial scores and six-month criterion physical and psychosocial reference standards. RESULTS The STarT-LE has good test-retest reliability (ICC=0.85, 95% CI: 0.78-0.91) and acceptable internal consistency (α=0.74). The convergent validity evidence was fair to moderate (ρ=0.53-0.68, p<0.001) and the predictive validity evidence was acceptable to excellent (AUC range: 0.73-0.84). CONCLUSIONS The STarT-LE has adequate properties for use in patients with lower extremity fracture. Future larger scale studies are needed to validate risk cutoffs.