Comparison of EQ-5D-3L and 5L versions following operative fixation of closed ankle fractures

Abstract

Abstract Purpose To undertake the first testing and comparison of measurement properties for the EuroQol EQ-5D-3L and 5L in patients with ankle problems. Methods The cross-sectional postal survey of 959 patients aged ≥ 18 years, who underwent surgical treatment (ORIF) for unstable and closed ankle fractures in Eastern Norway. Both the EQ-5D-3L and 5L were included in a postal questionnaire in 2015, 3–6 years post surgery. Missing data, floor and ceiling effects, and response consistency were assessed. Tests of validity included comparisons with scores for the SF-36 and widely used ankle-specific instruments. The 5L version was assessed for test–retest reliability. Results There were 567 (59%) respondents; 501 completed both versions and 182 (61%) the 5L retest questionnaire. The 5L outperformed the 3L in tests of data quality and classification efficiency. Correlations with scores for other instruments largely met expectations, those for the 5L being slightly higher. All 5L scores had acceptable levels of reliability. For the 5L index, the smallest detectable differences for group and individual comparisons were 0.02 and 0.20, respectively. Conclusion The 5L outperformed the 3L in terms of data quality, number of health states assessed and tests of validity. The 5L is recommended in research and other applications following surgery for ankle fracture but further testing including responsiveness to change is recommended at clinically relevant follow-up periods.