Evaluating Clinical Studies of Drug Efficacy Vol. In fact, the whole purpose of propensity scores is to put observational data into an RCT framework. Moreover, we think that direct comparisons of clinical outcomes should carry more weight than the use of surrogate measures. For example, the effect of statins in preventing cardiovascular events may be due to improving lipid profiles or lowering of blood pressure or both. If we agree that a hierarchy of research studies is warranted, it is not clear how it would be developed.
Observational studies are necessary to monitor drug safety.
Randomized controlled trials are rarely carried out with a prior hypothesis relating to an adverse drug event. In fact, the assessment of adverse drug events is almost entirely dependent on observational data of a large number of subjects followed up over a long period. If we were the patient, we would side with the policy maker. Peter T. Donnan, PhD Douglas M. Steinke, MSc Jixian Wang, PhD Peter G. Davey, MD Thomas M. MacDonald, MD University of Dundee Dundee, Scotland 1. McAlister FA, Laupacis A, Wells GA, Sackett DL, for the Evidence-Based Medicine Working Group.