Influence of number needed to treat costs and outcome on preferences for a preventive drug

Nexoe, J., Kristiansen, I. S., Gyrd-Hansen, D. and Nielsen, J. B. (2005) Influence of number needed to treat costs and outcome on preferences for a preventive drug. Family Practice, 22 1: 126-131. doi:10.1093/fampra/cmh706

Author Nexoe, J.
Kristiansen, I. S.
Gyrd-Hansen, D.
Nielsen, J. B.
Title Influence of number needed to treat costs and outcome on preferences for a preventive drug
Journal name Family Practice   Check publisher's open access policy
ISSN 0263-2136
Publication date 2005-02
Sub-type Article (original research)
DOI 10.1093/fampra/cmh706
Volume 22
Issue 1
Start page 126
End page 131
Total pages 6
Place of publication Oxford, United Kingdom
Publisher Oxford University Press
Language eng
Formatted abstract
Background. The number needed to treat (NNT) has been widely recommended for communicating benefits from risk reductions. It has been claimed that NNT is easily understood and that it has intuitive meaning. There are, however, only few studies of lay people’s understanding of NNT.
Objective. The objective of this study was to explore whether lay people are sensitive to the magnitude of treatment effectiveness as expressed in terms of NNT, and whether the sensitivity is influenced by variation in the type of health outcome, variation in patients’ payment for the treatment or variation in the type of side effects.
Methods. In total, 2326 non-institutionalized Danes aged 18–91 years were interviewed face to face and asked whether they would consent to a treatment against a somewhat increased risk of death or heart attack. The respondents were allocated to different levels of effectiveness of treatment expressed as NNT of 10, 100, 200 or 400, different costs and different descriptions of adverse effects.
Results. The odds for consenting to therapy were little influenced by the magnitude of NNT, but were greater among married respondents and among those who had side effects presented in terms of headache and constipation.
Conclusion. In this study, the respondents’ choice of treatment was largely insensitive to the magnitude of NNT independently of variations in type of health outcome and costs. NNT may not be easily understood by lay people.

Keyword General practice
Number needed to treat
Outcome type
Randomized trial
Q-Index Code C1
Q-Index Status Provisional Code
Institutional Status Non-UQ

Document type: Journal Article
Sub-type: Article (original research)
Collections: Faculty of Health and Behavioural Sciences -- Publications
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Citation counts: TR Web of Science Citation Count  Cited 15 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 17 times in Scopus Article | Citations
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