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Library Quicklinks and Information

Evidence at Becker: Educational Resources

Resources and services to support evidence-based medicine and evidence-based practice at Washington University in St. Louis.

Search the Literature


Clinical Reasoning Toolkit    from the Society to Improve Diagnosis in Medicine


Appraise the Literature

Secrets to Healthy Skepticism by
Centre for Evidence-Based Medicine Worksheets

Duke Critical Appraisal Worksheets

A Simple Method for Evaluating the Clinical Literature by Robert J. Flaherty , MD  
Uses PP-ICONS (Problem, Patient/Population, Intervention, Comparison, Number of Patients, Statistics).

JAMA's User’s Guide to the Medical Literature

BMJ's How To Read a Paper by Trisha Greenhalgh

How to Read a Systematic Review and Meta-analysis and Apply the Results to Patient Care: Users’ Guides to the Medical Literature by M.H. Murad, et al.

Grading the Evidence

Tables and Scales


  • What is GRADE ?  (Grading of recommendations, assessment, development and evaluations) It is the most widely adopted tool for grading the quality of evidence for making recommendations. 

    Table 1. GRADE certainty ratings


      What it means

    Very low

      The true effect is probably markedly different from the estimated effect


      The true effect might be markedly different from the estimated effect


      The authors believe that the true effect is probably close to the estimated     effect


      The authors have a lot of confidence that the true effect is similar to          estimated effect

  • Oxford Centre for Evidence-Based Medicine 2011 Levels of Evidence
  • Oxford Centre for Evidence-Based Medicine 2009 Levels of Evidence: Table helps you grade evidence from 1-5 and recommendations from A-D
  • Systems to Rate the Strength of Scientific Evidence from AHRQ
  • PP-ICONS - A Simple Method for Evaluating the Clinical Literature: The “PP-ICONS” approach will help you separate the clinical wheat from the chaff in mere minutes. 


Classes and Consultations





You and your department, class, or work group are always welcome to contact Becker Medical Librarians for consultations and classes for in-person demonstrations of how to use any information tool or information technique.


Debbie Thomas

Associate Director, Health Information Services
ph: 314-362-9729



Diagnostic Test Calculator from Alan Schwartz
This calculator can determine diagnostic test characteristics (sensitivity, specificity, likelihood ratios) and/or determine the post-test probability of disease given given the pre-test probability and test characteristics. Given sample sizes, confidence intervals are also computed.

Risk Reduction Calculator from Alan Schwartz
Given information about the probability of an outcome under control and experimental treatments, this calculator produces measures of risk increase/decrease and number needed to treat or harm, including confidence intervals. If some patients were lost to follow-up, the calculator provides estimates for several different scenarios.