New evidence pyramid

Interesante articulo;

Evid Based Med doi:10.1136/ebmed-2016

New evidence pyramid

Open Access

  1. M Hassan Murad,
  2. Noor Asi,
  3. Mouaz Alsawas,
  4. Fares Alahdab

“The first and earliest principle of evidence-based medicine indicated that a hierarchy of evidence exists. Not all evidence is the same. This principle became well known in the early 1990s as practising physicians learnt basic clinical epidemiology skills and started to appraise and apply evidence to their practice. Since evidence was described as a hierarchy, a compelling rationale for a pyramid was made. Evidence-based healthcare practitioners became familiar with this pyramid when reading the literature, applying evidence or teaching students……”


The Changing Face of Clinical Trials: Pragmatic Trials

Interesante publicación en el NEJM.

Pragmatic Trials

Ian Ford, Ph.D., and John Norrie, M.Sc.

N Engl J Med 2016; 375:454-463August 4, 2016DOI: 10.1056/NEJMra1510059

Pragmatism in clinical trials arose from concerns that many trials did not adequately inform practice because they were optimized to determine efficacy.1 Because such trials were performed with relatively small samples at sites with experienced investigators and highly selected participants, they could be overestimating benefits and underestimating harm. This led to the belief that more pragmatic trials, designed to show the real-world effectiveness of the intervention in broad patient groups, were required. Medical researchers, both academic and commercial, must deliver health care innovations (drugs, devices, or other interventions) that are safe, beneficial, and cost-effective, and they must identify the subgroups for whom the innovation will provide the greatest benefit relative to risk. A broad view of an intervention, including approaches to improve its effectiveness, is critical. An ideal trial includes a population that is relevant for the intervention, a control group treated with an acceptable standard of care, and outcomes that are meaningful, and it must be conducted and analyzed at a high standard of quality. Pragmatic trials frequently include complex interventions, sometimes consisting of several interacting components2 and often involving the skills and experience of one or more health care professionals to deliver the intervention — for example, surgeons, physiotherapists, or cognitive behavioral therapists.

In this article, we do not provide a definitive exposition of the methods used for pragmatic trials. Rather, we explore the contexts in which a pragmatic design is most and least attractive and identify the strengths and limitations of — and challenges in implementing — pragmatic trials.”