Psychometric properties of the Reintegration to Normal Living Index for sepsis survivors

Abstract

Purpose: Return to a normal state of living is a key patient-relevant outcome for sepsis survivors. The Reintegration to Normal Living Index (RNLI) assesses self-perceived participation in patients with chronic disease, but its psychometric properties have been analyzed neither for patients after sepsis nor in a German patient cohort. This study aims to analyze the psychometric properties of the German version of the RNLI in sepsis survivors. Methods: In a prospective multicenter survey study, 287 sepsis survivors were interviewed 6 and 12 months after hospital discharge. Multiple-group categorical confirmatory factor analyses with three competing models were used to explore the factor structure of the RNLI. Concurrent validity was evaluated in relation to the EQ-5D-3L and the Barthel Index of Activities of Daily Living (ADL). Results: Regarding structural validity, all models showed an acceptable model fit. Because of high correlation between the latent variables in the two-factor models (up to r = 0.969) and for reason of parsimony, we opted for the common factor model to analyze the concurrent validity. Our analyses showed moderate positive correlations between RNLI score and ADL score (r ≥ 0.630), EQ-5D-3L visual analogue scale (r ≥ 0.656) and EQ-5D-3L utility score (r ≥ 0.548). The reliability assessed by McDonald’s Omega was 0.94. Conclusion: We found convincing evidence for good reliability, structural and concurrent validity of the RNLI in German sepsis survivors. We propose to use the RNLI in addition to generic health-related quality of life measures to assess the reintegration to normal living after sepsis.