Fig. 1

Analysis of cutoffs related to the persistence of delirium on day 3. a A classification and regression tree model used to determine the cutoff point for the number of drugs associated with the persistence of delirium on day 3. The root node splitting value was six. b A receiver operating characteristic curve used to determine the cutoff number of drugs associated with the persistence of delirium on day 3. The maximum Youden index was calculated at a cutoff of six drugs