ABSTRACT
Cardiovascular diseases, including peripheral vascular disease, cerebral vascular disease, coronary disease, disease of the renal artery, etc., are highly prevalent throughout the world. Nonetheless, there are differences among the various nations in mortality rates, application of therapeutic procedures, and risk-benefit statistics. It is important to consider these in designing clinical trials that now commonly are multinational. For example, U.S. clinicians tend to be very aggressive in applying arterial stents by catheter. This fact may introduce a treatment-bycountry interaction in clinical trials; this factor would require consideration in the plan for analysis and interpretation of data from such studies, and may affect the plan for inclusion of specific countries as a group in specific trials.
