Related Experiment Video
Updated: Feb 8, 2026

Oral Biofilm Sampling for Microbiome Analysis in Healthy Children
Published on: December 31, 2017
Oral contraceptives and venous thromboembolism: a case-control study designed to minimize detection bias
J P Realini1, C E Encarnacion, K N Chintapalli
1Department of Family Practice, University of Texas Health Science Center at San Antonio, USA.
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.
More Related Videos
04:28Utilizing an Orally Dissolving Strip for Pharmacological and Toxicological Studies: A Simple and Humane Alternative to Oral Gavage for Animals
Published on: March 23, 2016
07:12Design of a Cyclic Pressure Bioreactor for the Ex Vivo Study of Aortic Heart Valves
Published on: August 23, 2011
Related Concept Videos
Bias in Epidemiological Studies
PD Controller: Design
Designing a continuous-data controller requires selecting and linking components like adders and integrators, which are fundamental in Proportional,...
PI Controller: Design
Confirmation Biases
Types of Errors: Detection and Minimization
Absolute error in a measurement is the numerical difference from the true or central value. Relative error is the ratio between absolute error and the true or central value, expressed as a percentage.
Errors can be classified by source, magnitude, and sign. There are three types of errors: systematic, random, and gross.
Systematic or...
Hindsight Biases