Reliability and validity of the respiratory score in the assessment of acute bronchiolitis

Children with bronchiolitis from Hospitals Universiti Sains Malaysia (HUSM) and Hospital Kota Bharu (HKB) were student using the Kristjansson Respiratory Score and the Wang Respiratory Score respectively. Saturation of oxygen (S(a)O(2)) was measured with a pulse-oximeter while the child is breathing room-air. Two observers assessed the respiratory scores in all children independently. The correlation between respiratory scores and S(a)O(2) was assessed using Spearman's Rho, and the inter-rater reliability of respiratory scores determined using intraclasscorelation coefficient. There were 29 children in HUSM and 25 from HKB with a median age of 8 months (IQR 4.5 months) and 9 months(IQR 7 months) respectively. In HUSM, the median Kristjansson Respiratory Score for both observers was 4 (IQR 2), and the median S(a)O(2) was 96% (IQR 3%). The correlation coefficient between the Kristjansson Respiratory Score and S(a)O(2) for the first observer was - 0.75 (p <0.001), and for the second observer -0.73 (p <0.001). In HKB, the median Wang Respiratory Score was also similar for both observers (median 4 IQR 4.5), and the median (IQR) for S(a)O(2) was 96% (2%). The correlation coefficient between the Wang Respiratory Score and S(a)O(2) for the first observer was -0.41 (p = 0.04) and for the second observer -0.43 (p = 0.03). The inter-rater reliability between the first and second observer was high for both the Kristjansson Respiratory (ICC 0.89) and the Wang Respiratory Scores (ICC 0.99). In conclusion the validity of the Kristjansson Respiratory Score was high whereas the validity of the Wang Respiratory Score was moderate in the assessment of the severity of acute bronchiolitis. Both respiratory scores and physical signs showed high agreement between observers. The Kristjansson Respiratory Score should be considered for use by medical personnel in the assessment of the severity of acute bronchiolitis in children.