Number needed to treat: Difference between revisions

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imported>Robert Badgett
(New page: The '''number needed to treat''' is a way of summarizing the benefit of an intervention to improve health care.<ref name="pmid3374545">{{cite journal |author=Laupacis A, Sackett DL, Robert...)
 
imported>Robert Badgett
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:<math>\mbox{Experimental event rate}=\left (\frac{\mbox{Cell A}}{\mbox{Cell A + Cell B}}\right )</math>
:<math>\mbox{Experimental event rate}=\left (\frac{\mbox{Cell A}}{\mbox{Cell A + Cell B}}\right )</math>


:<math>\mbox{Control event rate}=\left (\frac{\mbox{Cell C}}{\mbox{Cell C + CellD}}\right )</math>
:<math>\mbox{Control event rate}=\left (\frac{\mbox{Cell C}}{\mbox{Cell C + Cell D}}\right )</math>


===Measures of efficacy===
===Measures of efficacy===

Revision as of 07:13, 9 December 2007

The number needed to treat is a way of summarizing the benefit of an intervention to improve health care.[1] The calculations are derived from the results of a randomized controlled trial of an intervention.

Two-by-two table for a screening program
Outcome
Present Absent
Intervention Intervention group Cell A Cell B Total in intervention group
Control group Cell C Cell D Total in control group
Total with outcome Total without outcome

Calculations

Event rates

Measures of efficacy

Example

References

  1. Laupacis A, Sackett DL, Roberts RS (1988). "An assessment of clinically useful measures of the consequences of treatment". N. Engl. J. Med. 318 (26): 1728–33. PMID 3374545[e]

See also

Randomized controlled trial