Cesarean delivery rates may not be a useful measure of obstetric quality
Research Activities, November 2010, No. 363
There are currently no uniformly accepted measures of obstetrical quality. The risk-adjusted cesarean delivery rate historically has been a proposed quality measure. Earlier studies have suggested that both higher-than-expected and lower-than-expected rates may be associated with adverse maternal and neonatal outcomes. However, a new study suggests that risk-adjusted cesarean delivery rates may not be a useful measure of obstetric quality.
The researchers correlated risk-adjusted cesarean delivery rates with important maternal and neonatal outcomes in a study of 845,000 women from 401 hospitals in California and Pennsylvania. Their study found that 60 percent of 107 hospitals with lower-than-expected risk-adjusted cesarean delivery rates had a higher-than-expected rate of at least one of six adverse outcomes. This compared with 36.1 percent of the as-expected group and 19.6 percent of hospitals with higher-than-expected risk-adjusted cesarean delivery rates. On the other hand, hospitals with higher-than-expected cesarean delivery rates had similar rates of adverse outcomes as the as-expected hospitals on the other six delivery outcome measures.
The researchers stress that the lack of a correlation between a higher-than-expected cesarean delivery rate and adverse outcomes should not suggest that a higher-than-expected rate is desirable. Instead, it likely reflects an overuse of medical care and the performance of unnecessary procedures. What's more, the higher rate of c-sections did not result in improved outcomes. The study evaluated all the women from the hospitals and a smaller subset of women delivering single babies for the first time with no history of prior cesarean delivery. The results for the smaller group were similar to those of the larger group.
The outcome measures were a composite maternal outcome measure, a composite neonatal outcome measure, and four patient safety indicators from the Agency for Healthcare Research and Quality (AHRQ): birth trauma, injury with instrumented vaginal delivery, injury with noninstrumented vaginal delivery, and injury with cesarean delivery. This study was supported in part by the Agency for Healthcare Research and Quality (HS15696).
See "Evaluating risk-adjusted cesarean delivery rate as a measure of obstetric quality," by Sindhu K. Srinivas, M.D., Corinne Fager, M.S., and Scott A. Lorch, M.D. in the May 2010 Obstetrics and Gynecology 115(5), pp. 1007-1013.