Establishing the minimal clinically important difference of the EQ-5D-3L in older adults with a history of falls.

Purpose: Establish the minimal clinically important difference (MCID) of a health-related quality of life (HRQoL) measure-the EuroQol EQ-5 Dimensions-3 Level (EQ-5D-3L)-in older adults with a history of falls.

Methods: This study is a secondary analysis of 255 complete cases who were enrolled in a 12-month randomized controlled trial (NCT01029171; NCT00323596); participants were randomized to the Otago Exercise Program (OEP; n = 126/172; Age:81.2 ± 6.2 years; 60.3% Female) or control (CON; n = 129/172; Age:81.7 ± 5.7 years; 70.5% Female). Participants completed the EQ-5D-3L and Visual Analogue Scale (VAS) at baseline and 1-year. The VAS was associated with HRQoL and was the health status anchor (VAS minimal improvement = 7 to 17, maximal improvement ≥ 18, minimal decline =  - 7 to - 17, maximal decline ≤  - 18 points). We used four distinct approaches to estimate MCID ranges: (1) anchor-based change differences of the EQ-5D-3L (1-year minus baseline); (2) anchor-based beta coefficients from ordinary least squares regressions (OLS); (3) anchor-based receiver operating characteristic (ROC), and 4) distribution-based standard deviation and standardized effect size of 0.5.

Results: EQ-5D-3L MCID ranges for minimal improvements (OEP = 0.028 to 0.059; CON = 0.007 to 0.051), maximal improvements (OEP = 0.059 to 0.090; CON = 0.051 to 0.090), minimal declines (OEP =  - 0.029 to - 0.105; CON =  - 0.015 to - 0.051), and maximal declines (OEP =  - 0.018 to - 0.072; CON =  - 0.018 to - 0.082) were established using change difference, OLS, and distribution-based methods. The ROC area under the curve was poor, thus, it was not used to estimate the MCID.

Conclusions: Our results will assist in the interpretation of changes in HRQoL, as measured by the EQ-5D-3L, in older adults with a history of falls.