Validation study of two Standardised Respiratory Severity Scores (LIBSS and ReSVinet) in infants presenting to tertiary hospitals in Rwanda

Abstract

Background: There is a large burden of respiratory disease in infants in the sub-Saharan Africa region. The aim of this study was to assess the validity of two standardized respiratory distress severity scores (LIBSS and ResVinet) in the Rwandan population.

Methods: A cross-sectional validation study was conducted in four tertiary hospitals in Rwanda. Infants presenting with difficulty in breathing were included. The LIBSS and ResVinet scores were independently employed by nurses and residents to assess severity of disease in each infant.

Results: 100 infants were recruited with a mean age of 201 days. Infants presented with pneumonia (n=51), bronchiolitis (n=36) and other respiratory infections (n=13). Thirty-three infants had severe disease and survival was 94%. Regarding inter-rater reliability, the intraclass correlation coefficient (ICC) for LIBSS between nurses and residents was 0.985 (CI: 0.978- 0.990, SD±16.7, p<0.001). For ResVinet ICC was 0.980 (0.971 - 0.987, SD±6.9, p<0.001). Regarding validity, the convergent validity (Pearson’s correlation) between LIBSS and ReSVinet for residents was R=0.815, (p<0.001) and R= 0.836 for nurses (p<0.001). Regarding criterion validity the area under the receiver operator curve (aROC) for admission to PICU or HDU was 0.956 (CI: 0.918-0.995, p<0.001) and 0.880 (CI: 0.798-0.962, p<0.001) for nurse completed LIBSS and ReSVinet respectively. The aROC for hospital admission was 0.976 (CI: 0.947-1.0, p<0.001) and 0.974 (CI: 0.944-1.0, p<0.001) respectively.

Conclusion: Both LIBSS and ResVinet demonstrated good reliability and validity results and they are therefore suitable for use in this population. Severity scores can be used as an adjunct to clinical assessment to identify infants with severe respiratory disease.