Evaluating Preference Trials of Oral Phosphodiesterase 5 Inhibitors for Erectile Dysfunction John P. Mulhall, Francesco Montorsi European Urology Volume 49, Issue 1, Pages 30-37 (January 2006) DOI: 10.1016/j.eururo.2005.09.001 Copyright © 2005 Elsevier B.V. Terms and Conditions
Fig. 1 One-way crossover trials of drugs may introduce several biases, as well as period and carryover effects. European Urology 2006 49, 30-37DOI: (10.1016/j.eururo.2005.09.001) Copyright © 2005 Elsevier B.V. Terms and Conditions
Fig. 2 Well designed crossover drug trials can minimize bias and period or carryover effects. European Urology 2006 49, 30-37DOI: (10.1016/j.eururo.2005.09.001) Copyright © 2005 Elsevier B.V. Terms and Conditions