RT Journal Article
SR Electronic
T1 Oral Contraceptives and Venous Thromboembolism: A Case-Control Study Designed to Minimize Detection Bias
JF The Journal of the American Board of Family
                Practice
JO J Am Board Fam Med
FD American Board of Family Medicine
SP 315
OP 321
DO 10.3122/jabfm.10.5.315
VO 10
IS 5
A1 Realini, Janet P.
A1 Encarnacion, Carlos E.
A1 Chintapalli, Kedar N.
A1 Rees, Chet R.
YR 1997
UL http://www.jabfm.org/content/10/5/315.abstract
AB Background: Previous epidemiologic studies of venous thromboembolism and oral contraceptive use are susceptible to bias in the detection of venous thromboembolic events. This case-control study uses a unique design to minimize the influence of detection bias. Methods: Nonpredisposed women younger than the age of 40 years who underwent pulmonary angiography, lower extremity venography, or lower extremity duplex Doppler sonography at a large urban hospital were classified into a case group or control group based on results of their diagnostic studies. Medical records were reviewed for a history of current oral contraceptive use. Results: Fifty-seven women met the study criteria during the 11-year study period. Seven of 9 women in the case group and 17 of 48 women in the control group were currently using oral contraceptives (odds ratio 6.38; 95 percent confidence limits 1.19, 34.2). Conclusions: The association previously noted between venous thromboembolism and oral contraceptive use is not due to bias in the detection of venous thromboembolic events.