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Evidence-Based Practice: Calculate Results

Explaining the Results (videos and articles)

Number Needed to Treat

How to calculate the number-needed-to-treat
Terry Shaneyfelt video (3 min)
The NNT Tutorial
Graham Walker video (4 min)
Number needed to treat
Phillip Sedgewick. BMJ 2010;341:c5614

Absolute Risk Reduction, Relative Risk Reduction, Relative Risk

How to calculate a relative risk.
Terry Shaneyfelt video (3 min)
Basic Statistics for Clinicians: Assessing the effects of treatment: measures of association
CMAJ. 1995 Feb 1;152(3):351-7. Erratum in: Can Med Assoc J 1995 Mar 15;152(6):813.

Odds Ratios

Gordon Guyatt explaining odds ratios
video (21 min)
How to calculate an odds ratio
Terry Shaneyfelt video (3 min)
Odds ratios
Philip Sedgwick. BMJ 2010;341:c4414

Intention-to-Treat

Intention-to-treat analysis - What it is and why is it important?
Terry Shaneyfelt video (5 min)
What is intention-to-treat analysis?
Allan Shaughnessy video (1 min)
What is the intention-to-treat analysis?
Philip Sedgewick BMJ 2013;346:f3662

Forest Plots

How to interpret a forest plot.
Terry Shaneyfelt video (5 min)

Interpreting and Understanding Meta-Analysis Graphs: A Practical Guide
Aust Fam Physician. 2006 Aug; 35(8):635-8. PubMed PMID: 16894442

Confidence Intervals

Confidence intervals
Terry Shaneyfelt video (5 min)

Sensitivity, Specificity and Likelihood ratios

Sensitivity & specificity
H. Gilbert Welch video (8 min)
How to calculate sensitivity
Terry Shaneyfelt video (4 min)
How to calculate specificity
Terry Shaneyfelt video (3 min)
What are likelihood ratios and how are they used
Terry Shaneyfelt video (10 min)

More...

EBP Calculators

Nomogram Handout

EBM Calculator
Interactive Nomogram
Works best with Internet Explorer. Requires Shockwave Player.
EBM and Decision Tools (Interactive Diagnostic Tool)

BMJ Statistical Notes series by DG Altman

Grimes and Schulz series on statistics in Lancet

The Good Clinical Practice guideline: a bronze standard for clinical research
Lancet 2005; 366: 172–74