Fig 3 Physicians’ practice patterns by years of experience: adjusted outcomes with 95% confidence areas. Estimates were generated from negative binomial (cesarean delivery rate) or linear (comorbidity and delivery volume) regression with adjustment for state and secular trend. Cesarean delivery rate model also controlled for total number of deliveries per year. Heteroskedasticity robust standard errors accounted for repeated observations per physician. Confidence areas were further adjusted for multiple comparisons with Sidak’s method