Fitting in? Physician practice style after forced relocation.

Objective: This study aims to examine how variation in physicians' treatment decisions for newborn deliveries responds to changes in the hospital‐level norms for obstetric clinical decision‐making. Data Sources: All hospital‐based births in Florida from 2003 through 2017. Study Design: Difference‐in‐differences approach is adopted that leverages obstetric unit closures as the source of identifying variation to exogenously shift obstetricians to a new, nearby hospital with different propensities to approach newborn deliveries less intensively. Data Extraction: Births attributed to physicians continuously observed 2 years before the closure event and 2 years after the closure event (treatment group physicians) or for identical time periods around a randomly assigned placebo closure date (control group physicians). Principal Findings: All of the physicians meeting our inclusion criteria shifted their births to a new hospital less than 20 miles from the hospital shuttering its obstetric unit. The new hospitals approached newborn births more conservatively, and treatment group physicians sharply became less aggressive in their newborn birth clinical management (e.g., use of C‐section). The immediate 11‐percentage point (33%) increase in delivering newborns without any procedure behavior change is statistically significant (p value <0.01) and persistent after the closure event; however, the physicians' payer and patient mix are unchanged. Conclusions: Obstetric physician behavior change appears highly malleable and sensitive to the practice patterns of other physicians delivering newborns at the same hospital. Incentives and policies that encourage more appropriate clinical care norms hospital‐wide could sharply improve physician treatment decisions, with benefits for maternal and infant outcomes. [ABSTRACT FROM AUTHOR]