Infant and toddler disease score was useful for risk of hospitalization based on data from administrative claims

ObjectiveTo develop the infant and toddler disease score (IDS), a population-based predictive tool of morbidity status in infants and toddlers, based on data from administrative claims.Study Design and SettingA prospective cohort study was conducted, including 35,580 children less than 2 years of age in June 2003 from the French “ERASME” database (mean follow-up 13 months). The outcome variable was incident hospitalization during the follow-up year, that is, before the second birthday for infants and before the third for toddlers. Risk factors before inclusion (age, health care use, medications) were assessed in a 50% random sample (construction sample) by a logistic regression model. Beta coefficients were summed up to obtain the IDS. The IDS was then validated for the remaining 50% of the study population (validation sample).ResultsThe major variables significantly associated with the outcome were long-term disability, younger age, and ≥1 hospitalization before inclusion. The risks of hospitalization estimated by the IDS were concordant in the construction and validation samples.ConclusionThe IDS is a useful index for the risk of hospitalization of infants and toddlers in relation to their morbidity status and may be used for adjustment in pharmacoepidemiologic studies using administrative claims databases.