Multivariable Analysis
The variables included in the multivariable analysis included prematurity, poor feeding, nasal flaring and/or grunting and previous wheezing episodes requiring hospitalization. The risk points assigned to each predictor variable appear in Table 2. The total risk score ranged from 0 to 10 points. The overall clinical risk score for escalated care and estimated absolute percent risk of escalated care within 5 days of admission to the emergency room appear in Table 3.
The model have a sensitivity of 7%, specificity of 99.6%, positive predictive value of 1% and negative predictive value of 92.94%, a percentage of cases correctly classified of 87.8% with AUC for the risk score was 0.728, Figure 1. Figure 1 and 2 show corrected average AUC and calibration plots (slope= 1.09). The tenfold cross-validation revealed a corrected average AUC of 0.70 (CI 95% 0.60-0.74) with mean over-optimism obtained by a bootstrapping of 0.068% (Standard error: 0.0031). The risk score model had an excellent calibration and goodness of fit through the Hosmer–Lemeshow test (p = 0.47).