Cesarean rates may be misleading

Unadjusted figures can skew findings

A recent study suggests that unless cesarean section rates are adjusted for clinical factors, comparing them may be a flawed method for grading the performance of hospitals.1

Failing to account for patient characteristics that drive up cesarean rates can produce misleading results. "Rankings that fail to account for clinical factors that increase the risk of cesarean delivery may be methodologically biased and misleading to the public," say the researchers from Case Western Reserve University and the Quality Information Management Program, both located in Cleveland.

The study ranked 21 Cleveland-area hospitals based on the traditional ratings method, then compared those results to rankings that adjusted for the presence of patient risk factors such as maternal illness, maternal substance abuse, breech birth, or fetal abnormalities. There were considerable differences. For example, two of the 21 hospitals deemed subpar under the old system rose to levels of acceptable quality, while two others dropped from acceptable status to substandard status. The study found that the overall cesarean delivery rate was 15.9%, but varied from 6.3% to 26.5% among the different hospitals.


1. Aron DC, Harper DL, Shepardson LB, et al. Impact of risk-adjusting cesarean delivery rates when reporting hospital performance. JAMA 1998; 279:1,968-1,972.