Development and validation of a continuously age-adjusted measure of patient condition for hospitalized children using the electronic medical record.

•The first continuously age-adjusted measure of risk for pediatric patients.•A new method to compute age-adjusted risk, based on the Rothman Index excess risk curves.•Age-adjusted risk curves validated by comparison with expert-derived functions.•Model validated in predicting 24-h mortality, c=0.93, 0.93 and 0.95 at three pediatric hospitals.•Pediatric Rothman Index (pRI) signals patient deterioration prior to unplanned ICU transfer.