Skip to Main Content

Nursing Research Resources: Evidence

A guide for researching Nursing Information

Types of Evidence

EPM Pyramid

EBM Pyramid and EBM Page Generator, copyright 2006 Trustees of Dartmouth College and Yale University. All Rights Reserved.  Produced by Jan Glover, David Izzo, Karen Odato and Lei Wang.

Filtered Information

Filtered Information will appraise the quality of studies and usually make practice recommendations. They have been "filtered" by being critically-appraised and evaluated by other experts.  


Types of Filtered information are:

Systematic Reviews / Meta-Analyses

Authors of a systematic review ask a specific clinical question, perform a comprehensive literature search, eliminate the poorly done studies and attempt to make practice recommendations based on the well-done studies. A meta-analysis is a systematic review that combines all the results of all the studies into a single statistical analysis of results.

Critically-Appraised Topics

Authors of critically-appraised topics evaluate and synthesize multiple research studies.

Critically-Appraised Individual Articles

Authors of critically-appraised individual articles evaluate and synopsize individual research studies.


Unfiltered Information

Unfiltered Information sources have not been evaluated by others.  They are usually more recent and up-to-date than filtered sources but typically only look at one situation, trial or special interest. 


Types of Unfiltered information are:

Randomized Control Trial

An RCT is a clinical trial in which the subjects are randomly distributed into groups that are either subjected to the experimental procedure (such as use of a drug) or that serve as controls.  It is the research design considered to provide the most reliable evidence for evaluating the effectiveness of an intervention.

Cohort Study

A study designed to determine the relationship between a condition and a characteristic shared by some members of a group. The population selected is healthy at the beginning of the study. Some of the members of the group share a particular characteristic, such as cigarette smoking. The researcher follows the population group over a period of time, noting the rate at which a condition, such as lung cancer, occurs in the smokers and in the nonsmokers.

Case Control Study

A study where previously existing incidents of a medical condition are used in lieu of gathering new information. A group of patients with a particular disease or disorder, such as myocardial infarction, is compared with a control group of persons who have not had that medical problem. The two groups, matched for age, sex, and other personal data, are examined to determine which possible factor (e.g., cigarette smoking, coffee drinking) may account for the increased disease incidence in the case group.

Background Information

An overview or general awareness type of source.  It may simply be a literature review or the observations or intended simply to inform.

Scholarly Journals vs. Popular Magazines

Using peer-reviewed or "scholarly" journals for the first time can be a little intimidating.  

Use this chart to help figure out where a source falls.

Journals vs. Magazines

  Journals Magazines

Articles are published according to the results of the study or research. Can include a literature review to give context to where article intersects in relation to other research.  Can provide updates if research or conclusions change. 

Articles will usually reflect an ongoing issue in the world or recent findings from an experiment.  Information does not necessarily need to be up to date or current.


Typically offer original findings and research experiments or literature reviews of current (at time of publication) research. They can often use professional language and make assumptions that the audience has background knowledge/interest in the subject.  You may know all the words, but you may not know what they mean in context.

Secondary discussion of others' research and findings.  Intended for a general audience and often provide an overview or summary of a subject/problem.  May not necessarily look in-depth into a subject. 


Written by professionals who are experts and scholars in the field with credentials. Articles will demonstrate "proper scholarship" and contain citations and a bibliography.

Written by reporters or staff writer who is a journalist but not necessarily an expert in the field. Oftentimes, there is no author listed.  May refer to other articles/research but do not provide citations.


Articles are evaluated by Peer Reviewers who are experts in the field.  Articles are reviewed for accuracy, errors, and replication by other experts in the field before being published. (May take years to get an article published) 

Facts and reporting may be checked by editors for accuracy but not for replication. 


To report on Original Research and to make the relevant information available to the scholarly community in the discipline.  Articles will often be structured - including an abstract, goals and objectives, methodology, results, discussion, and conclusion.  

Inform general readers about a subject, to entertain, to promote a point of view , or to sell products.  Articles are much less structured and free flowing.  May not present evidence or a conclusion. 


  • JAMA: The Journal of the American Medical Association

  • Journal of Nursing Administration

  • Science

  • Prevention

  • Psychology Today

  • Consumer Reports on Health

  • Time Magazine