Table 18.1Percentage with poor outcomes

% Control with poor outcomes% intervention with poor outcomesRRRRRARR (%)NNT
60400.670.33205
30200.60.331010
15100.670.33520
310.670.33250

From: Chapter 18, Relative risk, relative and absolute risk reduction, number needed to treat and confidence intervals

Cover of Smart Health Choices
Smart Health Choices: Making Sense of Health Advice.
Irwig L, Irwig J, Trevena L, et al.
London: Hammersmith Press; 2008.
Copyright © 2008, Professor Les Irwig, Judy Irwig, Dr Lyndal Trevena, Melissa Sweet.

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