The DOI matches its Crossref record; 10 of the 10 references it cites were found in a registry or an index.
Numbers needed to treat derived from meta-analyses---sometimes informative, usually misleading
Open accessAbstract
The number needed to treat—the number of patients who must be treated to prevent one adverse outcome—is a widely used measure. 1 2 It is increasingly being calculated by pooling absolute risk differences in trials included in meta-analyses. 3 4 This option is available in statistical software and the Cochrane Database of Systematic Reviews . 5 6 In this paper, we examine pooled numbers needed to treat derived from trials and meta-analyses of interventions to prevent cardiovascular disease. We show that a pooled number needed to treat may be misleading because of variation in the event rates in trials, differences in the outcomes considered, effects of secular trends on disease risk, and differences in clinical setting. The number needed to treat should be derived by applying the relative risk reductions from treatment which have been estimated by trials or meta-analysis to relevant baseline risks for different types of patients. This provides a range of possible numbers needed to treat in different patient groups. ### Summary points Numbers needed to treat are often used to summarise treatment effects in a clinically relevant way They are derived from the baseline risk without treatment and the reduction in risk achieved with treatment Numbers needed to treat are sensitive to factors that change the baseline risk such as the outcome considered, patients' characteristics, secular trends in incidence and case fatality, and the clinical setting Pooled numbers needed to treat derived from meta-analyses can be seriously misleading because the baseline risk often varies appreciably between the trials Applying the pooled relative risk reductions calculated from meta-analyses or individual trials to the baseline risk relevant to specific patient group produces a useful number needed to treat The interventions selected for study were use of statins for lowering cholesterol concentrations in primary and secondary prevention of coronary heart disease.7 …
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Cites
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Meta-analysis: Principles and procedures
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The number needed to treat: a clinically useful measure of treatment effect
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Confidence intervals for the number needed to treat.
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Meta-analysis. Beyond the grand mean?
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Cited by
Interventions for preventing falls in older people living in the community
Gillespie, L. D., Robertson, M. C., Gillespie, W. J., Sherrington, C., Gates, S., Clemson, L., & Lamb, S. E. (2012) · Cochrane Database of Systematic Reviews · doi:10.1002/14651858.cd007146.pub3 · Cited by 3,966
Interpretation of the evidence for the efficacy and safety of statin therapy
Collins, R., Reith, C., Emberson, J., Armitage, J., Baigent, C., Blackwell, L., Blumenthal, R., Danesh, J., Smith, G. D., DeMets, D., et al. (2016) · The Lancet · doi:10.1016/s0140-6736(16)31357-5 · Cited by 1,857
Self-citationGraham (2007) · doi:10.1097/01.hjr.0000277983.23934.c9 · Cited by 1,647
Antiplatelet agents for preventing pre-eclampsia and its complications
Duley, L., Henderson-Smart, D. J., Meher, S., & King, J. F. (2007) · Cochrane Database of Systematic Reviews · doi:10.1002/14651858.cd004659.pub2 · Cited by 1,016
Leucht, S., Arbter, D., Engel, R. R., Kissling, W., & Davis, J. M. (2009) · Molecular Psychiatry · doi:10.1038/sj.mp.4002136 · Cited by 489
Metadata
- Authors
- Smeeth, L., Haines, A., & Ebrahim, S.
- Venue
- BMJ
- Publisher
- BMJ
- Published
- 1999-06-05
- Volume
- 318
- Issue
- 7197
- Pages
- 1548-1551
- ISSN
- 0007-1447 (ISSN-L)
- 0959-8138
- 1468-5833
- OpenAlex
- W2026077821
- Cited by
- 302
- References
- 10
- FWCI
- 32.86
- Type
- journal article
- Language
- en
- Open access
- green
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