Comparative effectiveness research: decision-based evidence.

In the clinical research context, comparative effectiveness research (CER) refers to the comparison of several health-care interventions administered under real-world conditions to individuals representative of the day-to-day clinical practice target population. We provide a brief history of CER and argue that CER can be used to deliver useful, but currently lacking information. Three study designs that can accomplish this are discussed, and incorporating CER into cost-benefit analyses is examined.

When ethics precludes randomization: put prospective, matched-pair observational studies to work.

Randomized, controlled clinical trials (RCTs) may be possible, permissible, and practical in certain circumstances, but ethical or practical considerations often preclude their utilization. In many such cases, ethical objections will not apply to a similarly oriented, prospective, matched-pair observational study. Additionally, if the methodological rigor associated with the RCT is maintained, potential epistemic losses due to eliminating randomization will be mitigated.

Patient preference clinical trials: why and when they will sometimes be preferred.

In a preference clinical trial (PCT), two or more health-care interventions are compared among several groups of patients, at least some of whom have purposefully chosen the intervention to be administered to them. This stands in contrast to the randomized, controlled clinical trial (RCT), where patients are randomly assigned to receive one of the available test interventions. This article argues that when comparing two interventions, A and B, when blinding (or masking) the interventions is difficult or impossible and at least some of the potential participants prefer one or the other of the interventions, then the use of a PCT merits consideration.