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

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.

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).

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.

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.