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Optometry and Vision Science Research Guide: Evidence-based Practice

Research resources and information for vision science.
  Asking and answering clinical questions (PICO)
  Critical appraisal, reading the evidence
  Filtered information, peer-reviewed
  Summaries: Point-of-care tools (CPS, UpToDate)
  Syntheses: systematic reviews
  Unfiltered information, peer-reviewed
  Studies: Clinical trials, interventional (randomized, controlled) and observational (cohort, cases)

What is Evidence-based practice?

Evidence-based practice "requires the integration of the best research evidence with our clinical expertise and our patient's unique values and circumstances." 1

1 Strauss, S. E. (2005) Evidence-based medicine : how to practice and teach EBM . 3rd ed. Edinburgh ;: Elsevier/Churchill Livingstone.

Filtered and unfiltered information

The 4s's: Studies (unfiltered information), and Syntheses, Synopses, and Summaries (filtered information)
Filtered Information

Filtered information, in this context, is pre-appraised evidence. 

To get filtered or “secondary” information, evidence from our primary literature is synthesized and evaluated. Those processes of evaluation, synthesizing data, and synopses take time and a lot work. 

Filtered literature will often provide a more definitive answer than individual research reports.

Sources containing filtered information
Based on analysis of synopses Summaries and systems: Point-of-care tools
 Based on analysis of syntheses Synopses: Clinical practice guidelines, evidence-based textbooks.
Based on analysis of original research studies Syntheses: systematic reviews, meta-analyses, and literature and scoping reviews.


Unfiltered Information

Unfiltered information includes original research studies that have not yet been synthesized or aggregated. As such, they can be more difficult to read, interpret, and apply to practice. 

Unfiltered does NOT mean that the research has not been peer-reviewed. This term refers to  study design, not quality. 

Studies, original research
  Randomized Controlled Trials (RCTs):
  Cohort studies: Prospective and retrospective cohort studies.
  Case-controlled studies: case reports and case series
  Laboratory studies: in-vitro trials

Evidence-based medicine centres