Hospitalization rates of children with croup in Ontario

Croup is a common problem, with an annual incidence of 1.5% in children under two years of age. In 1990, the Hospital Medical Records Institute (HMRI) labelled croup as a condition that "may not require hospitalization (MNRH)". This implied agreement among experts that some croup cases may be appropriately shifted from in-patients to out-patients. Based on the HMRI 1992/1993 hospital discharge data, admission rates of croup were calculated for all counties in Ontario. Minor variability in admission rates was observed in Ontario (fivefold difference between the highest and lowest, ie, 370.5 and 72.8 per 100,000 children, respectively). Findings from this study suggest minor variability in admissions of croup cases in 41 counties in Ontario. There were no significant indications from this study that unnecessary admissions of croup cases were a problem in Ontario. Therefore, the use and interpretation of MNRH for medical cases such as croup warrants further investigation.