Venue: The Fuqua School of Business, Duke University, 1 Towerview Drive, Durham, NC 27708-0120
Presentation
Does the Impact of Medical Research on Medical Practice Differ by Patient Education?
We examine the impact that medical research published in peer-reviewed journals has on the practice of medicine. We exploit the release of a New England Journal of Medicine article describing the additional risks of attempting a vaginal birth after having a c-section (VBAC). Immediately following this article, the national VBAC rate dropped by 16% and dropped by over 30% in some states. We find that the response was largest among more educated mothers (particularly those with graduate degrees). The response of less educated mothers catches up within about 1 year of the release of the study. There are similar patterns for whether the labor was induced, which the NEJM article noted as further increasing the risk of attempting a VBAC.
To insure that these changes are not simply capturing a natural time trends in VBAC rates, we investigate whether there are trend breaks on various other arbitrarily chosen dates before and after the release of the article (July 2000, October 2000, and February 2001). While the VBAC rate also dropped in these other periods reflecting a general downward trend during recent periods, the drops were very small in relation to the drop after July 2001, and there was no differential response by education in these placebo tests. In addition, we find no change in the C-section rate in response to the article among the group of mothers who had at least one previous birth but had not had a previous C-section (a group for which the article had no direct recommendations).
These educational differences in the response to information may operate through two channels. First, more educated mothers may be better able to access and act on new information themselves. Second, more educated mothers may go to doctors that are more responsive to the new information. We provide evidence that patients respond directly to the new information through their decision of where to give birth. For example, in the three months following the release of the NEJM article, mothers with more education who lived in counties with a high VBAC rate were more likely to travel to another county to give birth and they were attracted to those counties with low VBAC rates. Future research may provide a more clear differentiation between the role of patients and physicians in responding to new medical information.