Factors associated with obstetrician-gynecologists' response to the Women's Health Initiative trial of combined hormone therapy.

The Women's Health Initiative trial of combined estrogen and progestin (WHI E+P) ended prematurely after preliminary evidence indicated that harms exceeded benefits, with no cardiovascular benefit. There was controversy over the results and the decision to end the trial early, with many obstetrician-gynecologists expressing reservations about the evidence. The Research Department of the American College of Obstetricians and Gynecologists conducted a study regarding the WHI E+P, sending questionnaires to 2500 randomly selected Fellows; 703 Fellows returned usable surveys (28.1%). Despite almost universal awareness of the results of the WHI E+P (> 97%), almost half of the responding physicians did not find the results convincing and disagreed with the decision to stop the trial. In this further examination of the data, we identified characteristics of the respondents who were associated with either accepting or rejecting the WHI E+P. The year residency was completed, the relative importance a respondent attributed to randomized clinical trials (RCTs), concern about harms of action, and opinion of alternative therapies were significant factors. One of 5 respondents found the results convincing and agreed with the decision to end the trial (acceptors). One of 3 respondents did not find the results convincing and disagreed with the decision to end the trial (rejectors). Acceptors had completed residency more recently (1991 v. 1985, P = 0.001), rated evidence from RCTs as more important (P = 0.006), were more concerned with harms of action (22.4% v. 10.6%, P = 0.004), and were more likely to have a favorable opinion of alternative therapies to hormone therapy (64.1% v. 44.4%, P < 0.001).