Devices and clinical trials: overview and equipoise.

n an ideal world, our decision to enroll patients in clinical trials would be based on thoughtful, rational, informed, and balanced considerations of available and relevant scientific and clinical data. In reality, our decision making is based more often on our recent clinical experience and the opinions of those clinicians we value. To increase the appropriate and thoughtful enrollment of patients into clinical trials, it is helpful to examine how we make these decisions and the limitations of equipoise as a decision-making tool. Physicians particularly struggle with enrollment of patients in clinical trials when a given treatment, like endovascular therapy, is already available as part of the standard of care in a region. Ideally, physicians want to offer their patients the best available medical care as opposed to treatment in a randomized trial that is selected by chance. The ethical solution to this conundrum that has gained greatest acceptance among clinicians is the concept of equipoise. According to Freedman's classical formulation, clinical equipoise exists when there is no consensus within the expert clinical community about the comparative merits of the alternatives to be tested. 1 Yet, Miller and Joffe 2 note 5 considerations that argue against equipoise as the arbiter of the ethical legitimacy of randomized trials to evaluate new treatments, even for life-threatening or highly debilitating conditions (like stroke): the imprecision in defining the concept of equipoise, the reliance on expert opinion, the limitations of determining efficacy on the basis of surrogate outcomes, the high costs of new treatments , and the tendency toward premature termination of ran-domized clinical trials. The expert clinical community is a highly variable group and it is unclear what the minimal proportion of this hypothetical community should be to consider that the conditions for equipoise are met (eg, 50%, 25%, 10%, or 5%). It is also very likely that the expert community of stroke intervention-alists may have very different ideas concerning the evidence underlying a given interventional treatment than stroke neu-rologists or emergency physicians who are not interven-tionalists and whose clinical practice is not dependent on performing these procedures. Furthermore, however equi-poise might be specified, systematic published data are often not available to define the degree of consensus within the expert community to guide decisions about commencing or designing randomized clinical trials, or published guidelines may lag several years behind the current state of clinical and scientific knowledge. Even with such data, the fallibility …