Pediatric Return Visits to the Emergency Department: The Time to Return Curve.

OBJECTIVE: Although 72-hour return visits are a frequently reported metric for pediatric patients discharged from the emergency department (ED), the basis for this metric is not established. Our objective was to statistically derive a cutoff time point for the characterization of pediatric return visits. METHODS: We performed a retrospective cohort study using data of patients discharged from any of 44 pediatric EDs. We selected the first encounter per patient from January 1 to December 31, 2019, as the index encounter and included the first return visit within 30 days. We constructed a cumulative hazard curve to characterize the timing of return visits and constructed a multivariable adaptive regression spline model to identify a hinge point in return visit presentations. We identified the association between admission for early return visits and admission for late return visits using generalized linear mixed modeling. RESULTS: Of 1,986,778 index ED discharges, 193,605 (9.7%) ED return visits were included. A double-exponential decay model demonstrated superior fit compared with a single exponential model ( P < 0.0001). Multivariable adaptive regression spline modeling identified a hinge at 7 days. When comparing proportions of return visits leading to hospitalization between early (23.8%) and late (15.1%) return visits, early visits (≤7 days) had higher adjusted odds of hospital admission (adjusted odds ratio, 1.73; 95% confidence interval, 1.69-1.77) relative to late return visits (>7 days). Findings were similar in sensitivity analyses within age subgroups, Census region, and in which the diagnosis (using the Diagnosis and Grouping System) was the same between the index and return visit. Among return visits that occurred within 7 days of the index visit, 46.3% had the same diagnosis grouping in both visits. CONCLUSIONS: An empirically derived 7-day cutoff may be more appropriate for characterization of pediatric return visits to the ED. Encounters after this period had lower adjusted odds of admission.