Realini J P, Encarnacion C E, Chintapalli K N, Rees C R
Department of Family Practice, University of Texas Health Science Center at San Antonio, USA.
J Am Board Fam Pract. 1997 Sep-Oct;10(5):315-21.
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.
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.
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).
The association previously noted between venous thromboembolism and oral contraceptive use is not due to bias in the detection of venous thromboembolic events.
既往关于静脉血栓栓塞症与口服避孕药使用的流行病学研究在静脉血栓栓塞事件的检测中易产生偏倚。本病例对照研究采用独特设计以尽量减少检测偏倚的影响。
在一家大型城市医院接受肺血管造影、下肢静脉造影或下肢双功多普勒超声检查的40岁以下无易患因素的女性，根据诊断研究结果分为病例组或对照组。查阅病历以了解当前口服避孕药使用史。
在11年的研究期间，57名女性符合研究标准。病例组9名女性中有7名、对照组48名女性中有17名正在使用口服避孕药（比值比6.38；95%可信区间1.19，34.2）。
先前观察到的静脉血栓栓塞症与口服避孕药使用之间的关联并非由于静脉血栓栓塞事件检测中的偏倚所致。
