ReviewJournal of epidemiology and community health2002
Impact numbers: measures of risk factor impact on the whole population from case-control and cohort studies.
Review in Journal of epidemiology and community health, 2002. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 16 papers, 1 of them a synthesis that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
16 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Assessment of School Anti-Bullying Interventions: A Meta-analysis of Randomized Clinical Trials.JAMA pediatrics · 2021Pooled it
- A pandemic risk index to improve supply chains decision-making between US and Mexico: A COVID-19 case study.PloS one · 2025Article
- Association of Visiting the Physiotherapist with Mortality in the Spanish General Population: A Population-Based Cohort Study.Medicina (Kaunas, Lithuania) · 2023Article
- Association of sickle cell trait with adverse pregnancy outcomes in a population-based cohort.Acta obstetricia et gynecologica Scandinavica · 2023Article
- Impact of osteoporotic fracture type and subsequent fracture on mortality: the Tromsø Study.Osteoporosis international : a journal established as result of cooperation between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USA · 2020Article
- Article
- Survival, effect measures, and impact numbers after dementia diagnosis: a matched cohort study.Clinical epidemiology · 2019Article
- Number needed to treat (NNT) in clinical literature: an appraisal.BMC medicine · 2017Article
- Rheumatoid arthritis, anti-tumour necrosis factor treatment, and risk of squamous cell and basal cell skin cancer: cohort study based on nationwide prospectively recorded data from Sweden.BMJ (Clinical research ed.) · 2016Article
- Estimating the impact of smoking cessation during pregnancy: the San Bernardino County experience.Journal of community health · 2013Article
- Cardiovascular risk and all-cause mortality attributable to diabetes: Tehran lipid and glucose study.Journal of endocrinological investigation · 2012Article
- Effect of variable transmission rate on the dynamics of HIV in sub-Saharan Africa.BMC infectious diseases · 2011Article
- Using and Interpreting Adjusted NNT Measures in Biomedical Research.The open dentistry journal · 2010Article
- Calculating confidence intervals for impact numbers.BMC medical research methodology · 2006Article
- Communicating risks at the population level: application of population impact numbers.BMJ (Clinical research ed.) · 2003Review
- Impact numbers in health policy decisions.Journal of epidemiology and community health · 2002Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
objectiveTo describe new measures of risk from case-control and cohort studies, which are simple to understand and relate to numbers of the population at risk.
designTheoretical development of new measures of risk.
settingReview of literature and previously described measures. MAIN
resultsThe new measures are: (1) the population impact number (PIN), the number of those in the whole population among whom one case is attributable to the exposure or risk factor (this is equivalent to the reciprocal of the population attributable risk); (2) the case impact number (CIN) the number of people with the disease or outcome for whom one case will be attributable to the exposure or risk factor (this is equivalent to the reciprocal of the population attributable fraction); (3) the exposure impact number (EIN) the number of people with the exposure among whom one excess case is attributable to the exposure (this is equivalent to the reciprocal of the attributable risk); (4) the exposed cases impact number (ECIN) the number of exposed cases among whom one case is attributable to the exposure (this is equivalent to the reciprocal of the aetiological fraction). The impact number reflects the number of people in each population (the whole population, the cases, all those exposed, and the exposed cases) among whom one case is attributable to the particular risk factor.
conclusionsThese new measures should help communicate the impact on a population, of estimates of risk derived from cohort or case-control studies.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.