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National Information Center on Health Services Research and Health Care Technology (NICHSR)

NLM Resources for Informing Comparative Effectiveness

This page provides specialized searches of published research - PubMed - and research still in progress - HSRProj, and ClinicalTrials.gov - to help inform investigations of comparative effectiveness. See the description below the search boxes for more information about this project.

For clinical and comparative effectiveness studies written specially for patients and consumers, see PubMed Health, a growing resource that is being developed by NLM's National Center for Biotechnology Information.

Please help us improve these searches. Send us your comments here.


[Top]Top Description of this Project


The Federal Coordinating Council for Comparative Effectiveness Research (FCCCER) definition of Comparative Effectiveness Research focuses on studies in "real world" practice; the study designs used for conducting comparative research in practice settings are evolving and at present there are few studies conducted that have wide applicability beyond the settings in which they are based. The purpose of the search strategies presented here is to help inform discussions on or relating to comparative effectiveness by providing retrieval of a full-range of studies on the efficacy-effectiveness-effectiveness in the "real world" continuum. Conceptual organization of these searches has been based on work undertaken by Holve, E. and P. Pittman. A first look at the volume and cost of comparative effectiveness research in the United States [Internet]. Washington, DC: AcademyHealth; 2009 June [cited 2009 Oct. 14]. 20 p.

Clinical effectiveness studies cover a range of study designs with wide variation in terminology and they may be drawn from a variety of data sources. For this reason, the Randomized Controlled Trials and Systematic Review PubMed search strategies have been designed for sensitivity (that is, searches will retrieve many relevant citations but probably a few less relevant ones, too) while the PubMed Observational Studies search strategies have been designed for specificity (that is, searches will retrieve mostly relevant citations but may not include all citations that could be potentially relevant to a particular topic).

Federal Coordinating Council for Comparative Effectiveness Research definition:

Comparative effectiveness research is the conduct and synthesis of research comparing the benefits and harms of different interventions and strategies to prevent, diagnose, treat and monitor health conditions in "real world" settings. The purpose of this research is to improve health outcomes by developing and disseminating evidence-based information to patients, clinicians, and other decision-makers, responding to their expressed needs, about which interventions are most effective for which patients under specific circumstances.

  • To provide this information, comparative effectiveness research must assess a comprehensive array of health-related outcomes for diverse patient populations and subgroups.
  • Defined interventions compared may include medications, procedures, medical and assistive devices and technologies, diagnostic testing, behavioral change, and delivery system strategies.
  • This research necessitates the development, expansion, and use of a variety of data sources and methods to assess comparative effectiveness and actively disseminate the results.

The definition above is not meant to exclude randomized trials; however, these trials would need comparator arms other than placebo and be representative of populations seen in "real world" practice. Federal Coordinating Council for Comparativeness Research. Report to the President and the Congress, June 30, 2009 [Internet]. Washington, DC: The Council; 2009 [cited 2009 Oct. 14] p. 16.

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