Evidence based medicine is the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients. The practice of evidence based medicine means integrating individual clinical expertise with the best available external clinical evidence from systematic research.

Sackett DL, Rosenberg WMC, Gray JAM, Haynes RB, Richardson WS. Evidence based medicine: what it is and what it isn't. BMJ. 1996 Jan 13; 312 (7023): 71-2.

...research is one of the pillars of evidence-based practice.

Type of Reference	Pros	Cons	Examples	Evidence-based?
Websites	Easy to find Can be very current	Quality variable	MedlinePlus Child Development   Vaccine/Autism	May lead to evidence-based sources of information in traditional literature it the references. Expert Opinion
Textbooks	Quick and easy to use Provides summaries	Can be expensive Can be slow to update	The Lippincott Manual of Nursing Practice UpToDate	May summarize evidence and lead to evidence-based sources of information in the references. Expert Opinion
Journal Articles
Reviews (Narrative)	Provide summaries of what is known on specific topics	Methodology used in compiling the summaries may not be scientific or systematic	Headaches in children. Ovid	May lead to evidence-based sources of information in the references. Expert Opinion
Systematic Reviews	Provide systematically derived summaries of research studies on specific topics	Addresses a single research question Requires some research to already have been done on the research question	Factors influencing completion of multi-dose vaccine schedules in adolescents: a systematic review.	Evidence-based, secondary research References individual research articles
Meta-analyses	Provide systematically derived summaries of research studies on specific topics and applies statistical methods of analyses	Requires considerable amounts of research to have already been done on the specific research question	Prevalence of, and risk factors for, chronic idiopathic constipation in the community: systematic review and meta-analysis	Evidence-based Leads to individual research articles
Research Reports/Articles	Describes original research studies and reports on results	Can be time-consuming to read, interpret, and translate into clinical practice	Double-blind, placebo-controlled antibiotic treatment study of small intestinal bacterial overgrowth in children with chronic abdominal pain	Evidence-based research

Graphic overview of the different types of references and the quality or level of evidence they provide.

Simplified pyramid of levels of evidence	6S hierarchy of pre-appraised evidence