A comparison of two clinical scores for bronchiolitis. A multicentre and prospective study conducted in hospitalised infants

Abstract

Background: There are a number of clinical scores for bronchiolitis but none of them are firmly recommended in the guidelines.

Method: We designed a study to compare two scales of bronchiolitis (ESBA and Wood Downes Ferres) and determine which of them better predicts the severity. A multicentre prospective study with patients <12 months with acute bronchiolitis was conducted. Each patient was assessed with the two scales when admission was decided. We created a new variable "severe condition" to determine whether one scale afforded better discrimination of severity. A diagnostic test analysis of sensitivity and specificity was made, with a comparison of the AUC. Based on the optimum cut-off points of the ROC curves for classifying bronchiolitis as severe we calculated new Se, Sp, LR+ and LR- for each scale in our sample.

Results: 201 patients were included, 66.7% males and median age 2.3 months (IQR=1.3-4.4). Thirteen patients suffered bronchiolitis considered to be severe, according to the variable severe condition. ESBA showed a Se=3.6%, Sp=98.1%, and WDF showed Se=46.2% and Sp=91.5%. The difference between the two AUC for each scale was 0.02 (95%CI: 0.01-0.15), p=0.72. With new cut-off points we could increase Se and Sp for ESBA: Se=84.6%, Sp=78.7%, and WDF showed Se=92.3% and Sp=54.8%; with higher LR.

Conclusions: None of the scales studied was considered optimum for assessing our patients. With new cut-off points, the scales increased the ability to classify severe infants. New validation studies are needed to prove these new cut-off points.

Keywords: Bronchiolitis; Clinical scores; Diagnostic test; Infants; ROC curves.