P - Patient or Population: Describes the most important characteristics of the patient
I - Intervention: Describes the main intervention
C - Comparison: If appropriate, describes the main alternative being considered
O - Outcome: Describes what you are trying to accomplish, measure, improve or affect
T - Time: time for the intervention to achieve the outcome
Quick overview chart of scholarly or peer-reviewed journals vs. popular magazines developed the University of Michigan Shapiro Undergraduate and Shapiro Science Libraries.
| Journal [scholarly] | Magazine [popular] | |
| Content | Detailed report of original research or experiment. | Secondary report or discussion may include personal narrative, opinion, anecdotes. |
| Author |
Author's credentials are given, usually a scholar with subject expertise. | Author may or may not be named; often a professional writer; may or may not have subject expertise. |
| Audience |
Scholars, researchers, students. | General public; the interested non-Specialist. |
| Language |
Specialized terminology or jargon of the field; requires prior knowledge. | Vocabulary in general usage; understandable to most readers. |
| References | Bibliography Required. All quotes and facts can be verified. | Rare. Scanty, if any, information about sources. |
| Examples | Developmental Psychology, Journal of Abnormal Psychology. Almost anything with Journal in the title. Usually come with memberships in scholarly societies and are only available in libraries or by subscription. | Psychology Today, Discover, news magazines. Almost anything available |
A Meta-analysis takes a systematic
review one step further by combining all the results using accepted statistical
methodology.
Systematic Reviews usually focuses on a
specific clinical question and conducts an extensive literature search to
identify studies with sound methodology. The studies are reviewed, assessed,
and the results summarized according to the predetermined criteria of the
review question.
Randomized, controlled clinical trials. A prospective,
analytical, experimental study using primary data generated in the clinical
environment. Individuals similar at the beginning are randomly allocated to two
or more groups (treatment and control) and the outcomes of the groups are
compared after sufficient follow-up time.
A study that shows the efficacy of a
diagnostic test is called a prospective, blind comparison to a gold standard
study. This is a controlled trial that looks at patients with varying degrees
of an illness and administers both diagnostic tests -- the test under
investigation and the "gold standard" test -- to all of the patients
in the study.
Cohort studies identify a large
population who already has a specific exposure or treatment, follows them over
time (prospective), and compares outcomes with another group that has not been
affected by the exposure or treatment being studied. Cohort studies are
observational and not as reliable as randomized controlled studies, since the
two groups may differ in ways other than in the variable under study.
Case control studies are studies in which
patients who already have a specific condition or outcome are compared with
people who do not. Researchers look back in time (retrospective) to identify
possible exposures. They often rely on medical records and patient recall for
data collection. These types of studies are often less reliable than randomized
controlled trials and cohort studies because showing a statistical relationship
does not mean than one factor necessarily caused the other.
Case series and Case reports consist of
collections of reports on the treatment of individual patients or a report on a
single patient. Because they are reports of cases and use no control groups
with which to compare outcomes, they have no statistical validity.
From: Duke University Medical Center Library,
December 2005 (last retrieved January 20, 2009)
http://www.mclibrary.duke.edu/subject/ebm/searching/ebmresources.pdf