In Reply Dr Rhinehart and colleagues raise an important and controversial issue concerning the effect of thrombophilia on the risk of recurrent venous thromboembolism. They were concerned that the results of the PADIS-PE trial may be biased due to the inclusion of patients with identified and unidentified thrombophilia.
First, misclassification bias was avoided because thrombophilia testing was performed at the end of the study on stored frozen blood samples taken on the day of randomization using the same standardized laboratory techniques for all included patients by technicians blinded to the study treatment allocation.
Francis Couturaud, Guy Meyer, Dominique Mottier. Thrombophilia and the Risk of Recurrent Venous Thromboembolism—Reply. JAMA. 2015;314(18):1976. doi:10.1001/jama.2015.12610