Fitting in? Physician practice style after forced relocation

Abstract

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.

Keywords: newborn deliveries; obstetric unit closures; obstetrics; physician practice patterns.

FIGURE 1

Scatter plot of physician delivery treatment intensity versus peer physician treatment intensity at the same hospital. Each dot represents a physician who performed deliveries at a Florida hospital in 2010 and that physician's matched hospital‐based obstetric unit. The “deliveries without procedures rate” is calculated as the number of deliveries where no additional procedure was performed (e.g., no c‐section, vacuum, forceps, or other procedure) divided by all deliveries performed. The physician's rate is based on all facilities at which the physician performed deliveries in 2010. The corresponding facility rate is based on all other physicians' rates, excluding the “own” physician's rate, during 2010. Correlation coefficient is 0.513. The slope for the line of best fit is 0.791 (SE = 0.029).

FIGURE 2

Event study estimates for obstetrics (OB) unit closure effect. Panel A: Number of unique hospital OB units where physician delivers. Panel B: Rate of delivery with no procedure. In Panel A, the outcome variable is determined by the unique number of hospital facility identifiers at which a physician performs deliveries. In Panel B, the “deliveries without procedures rate” is calculated as the number of deliveries where no additional procedure was performed (e.g., no c‐section, vacuum, forceps, or other procedure) divided by all deliveries performed. All stacked DiD estimations include physician fixed effects. Vertical bars represent the 95% confidence intervals. Standard errors are clustered at the physician level.