Psychometric properties of the Spanish version of the EuroQol-5D-5L in previously hospitalized COVID-19 survivors with long COVID

Abstract The EuroQol 5-dimensions 5-levels (EQ-5D-5L) is a generic patient-reported outcome measures (PROM) used for evaluating health-related quality of life (HRQoL). No data on its psychometric properties in COVID-19 survivors is available. We aimed to describe internal consistency, test–retest reliability, and construct validity of the EQ-5D-5L in people with long-COVID. Ninety-three (n = 93) individuals previously hospitalized due to COVID-19 with post-COVID symptoms completed the EQ-5D-5L questionnaire twice one year after hospital discharge in a three-week interval. Internal consistency (Cronbach alpha and Omega value), test–retest reliability (kappa and ICC2,1) and construct validity (factor analysis), and floor/ceiling effects were calculated. No ceiling effect was observed in any dimension whereas the floor effect ranged from 53.76 to 94.62%. The overall Cronbach’s α value was 0.75 (95%CI 0.64–0.83) and the Omega ω value was 0.77 (95%CI 0.66–0.84), showing good internal consistency of the questionnaire. Further, Cronbach’s alpha values the of each dimension ranged from 0.63 to 0.77 whereas those for Omega values ranged from 0.70 to 0.79. The test–retest reliability of the total score was excellent (ICC2,1 0.86, 95%CI 0.798–0.911). The agreement percentage ranged from 85.13 to 96.77%; but kappa coefficients ranged from fair (κ: 0.37) to good (κ: 0.61). The factor analysis showed factor loadings from 0.585 to 0.813 supporting good construct validity. The EQ-5D-5L has good psychometric properties to be used as a PROM to assess HRQoL in hospitalized COVID-19 survivors with long-COVID