Electronic Version of the EQ-5D Quality-of-Life Questionnaire: Adaptation to a Brazilian Population Sample

Abstract

Objectives: To assess the measurement equivalence of the original paper version of an adapted tablet version of the EuroQol five-dimensional questionnaire (EQ-5D).

Methods: A randomly selected sample of 509 individuals aged 18 to 64 years from the general population responded to the EQ-5D at two time points separated by a minimum interval of 24 hours and were allocated to one of the following groups: test-retest group (tablet-tablet) or crossover group (paper-tablet and tablet-paper). Agreement between methods was determined using the intraclass correlation coefficient (ICC) and the κ coefficient.

Results: In the crossover group, the following ICC values were obtained: 0.76 (confidence interval [CI] 0.58-0.89) for EQ-5D scores and 0.77 (CI 0.68-0.84) for visual analogue scale in subjects responding first to the tablet version; 0.83 (CI 0.75-0.89) for EQ-5D scores and 0.75 (CI 0.67-0.85) for visual analogue scale in subjects responding first to the paper version. In the test-retest group, the ICC was 0.85 (CI 0.73-0.91) for EQ-5D scores and 0.79 (CI 0.66-0.87) for visual analogue scale. The κ values were higher than 0.69 in this group. The internal consistencies of the paper and tablet methods were similar.

Conclusions: The paper and tablet versions of the EQ-5D are equivalent. Test-retest and crossover agreement was high and the acceptability of the methods was similar among individuals.

Keywords: EQ-5D; EuroQol; cost-utility; electronic data capture; quality of life.