Using the number needed to treat in clinical practice

Weeks, Douglas L.; Noteboom, J.Timothy

doi:10.1016/j.apmr.2004.03.025

Cited by 29Statistical Methods in Clinical TrialsMeta-analysis and systematic reviewsStatistical Methods in Epidemiology

Using the number needed to treat in clinical practice

Weeks, Douglas L., Noteboom, J.Timothy·2004·Archives of Physical Medicine and Rehabilitation

DOI 10.1016/j.apmr.2004.03.025

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Abstract

The number needed to treat (NNT) is gaining attention as a method of reporting the results of clinical trails with dichotomous outcome measures. The NNT is defined as the number of patients who would need to be treated, on average, with a specific intervention to prevent 1 additional bad outcome or to achieve 1 desirable outcome in a given time period. Because it reports outcomes in terms of patient numbers, it is extremely useful to clinicians for making decisions about the effort expended with a particular intervention to achieve a single positive outcome. This special communication describes the NNT statistic and its utility for choosing clinical interventions.

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The acceptable number needed to treat depends on the context of the study.
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Authors: Weeks, D. L., & Noteboom, J. T.
Affiliations: Inland Northwest Health Services (US)
Regis University (US)
Corresponding author: Weeks, Douglas L.
ORCID: Weeks, Douglas L.
Venue: Archives of Physical Medicine and Rehabilitation
Publisher: Elsevier BV
Published: 2004-10
Volume: 85
Issue: 10
Pages: 1729-1731
ISSN: 0003-9993 (ISSN-L)
DOI: 10.1016/j.apmr.2004.03.025
OpenAlex: W2137227357
Cited by: 29
References: 22
Citations by year: 2026: 2 · 2025: 3 · 2023: 5 · 2022: 2 · 2021: 3 · 2018: 1 · 2017: 1 · 2016: 1 · 2013: 1 · 2012: 1
FWCI: 2.03
Type: journal article
Language: en
Open access: closed
Licence: www.elsevier.com/tdm/userlicense/1.0/ (tdm)
Locations: Archives of Physical Medicine and Rehabilitation (publishedVersion)
PubMed (publishedVersion)
ePublications at Regis University (Regis University) (submittedVersion)
Topics: Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Clinical Trials
Social Sciences › Decision Sciences › Statistics, Probability and Uncertainty › Meta-analysis and systematic reviews
Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Epidemiology
Keywords: number needed to treat, clinical trial reporting, binary outcomes, treatment decision-making, clinical intervention, patient numbers
MeSH terms: Clinical Trials as Topic, Data Interpretation, Statistical, Humans, Research Design, Confidence Intervals, Sample Size, Risk Assessment

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Using the number needed to treat in clinical practice

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