|
Preventive Fraction
In epidemiology, preventable fraction among the unexposed (PFu), is the proportion of incidents in the unexposed group that could be prevented by exposure. It is calculated as PF_u = (I_u - I_e)/I_u = 1 - RR, where I_e is the incidence in the exposed group, I_u is the incidence in the unexposed group, and RR is the relative risk. It is a synonym of the relative risk reduction. It is used when an exposure reduces the risk, as opposed to increasing it, in which case its symmetrical notion is attributable fraction among the exposed. Numerical example See also * Population Impact Measures * Preventable fraction for the population In epidemiology, preventable fraction for the population (PFp), is the proportion of incidents in the population that could be prevented by exposing the whole population. It is calculated as PF_p = (I_p - I_e)/I_p, where I_e is the incidence in the ... References {{Clinical research studies Epidemiology Medical statistics ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epidemiology
Epidemiology is the study and analysis of the distribution (who, when, and where), patterns and determinants of health and disease conditions in a defined population. It is a cornerstone of public health, and shapes policy decisions and evidence-based practice by identifying risk factors for disease and targets for preventive healthcare. Epidemiologists help with study design, collection, and statistical analysis of data, amend interpretation and dissemination of results (including peer review and occasional systematic review). Epidemiology has helped develop methodology used in clinical research, public health studies, and, to a lesser extent, basic research in the biological sciences. Major areas of epidemiological study include disease causation, transmission, outbreak investigation, disease surveillance, environmental epidemiology, forensic epidemiology, occupational epidemiology, screening, biomonitoring, and comparisons of treatment effects such as in clinical trials. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Relative Risk
The relative risk (RR) or risk ratio is the ratio of the probability of an outcome in an exposed group to the probability of an outcome in an unexposed group. Together with risk difference and odds ratio, relative risk measures the association between the exposure and the outcome. Statistical use and meaning Relative risk is used in the statistical analysis of the data of ecological, cohort, medical and intervention studies, to estimate the strength of the association between exposures (treatments or risk factors) and outcomes. Mathematically, it is the incidence rate of the outcome in the exposed group, I_e, divided by the rate of the unexposed group, I_u. As such, it is used to compare the risk of an adverse outcome when receiving a medical treatment versus no treatment (or placebo), or for environmental risk factors. For example, in a study examining the effect of the drug apixaban on the occurrence of thromboembolism, 8.8% of placebo-treated patients experienced the disease, b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Relative Risk Reduction
In epidemiology, the relative risk reduction (RRR) or efficacy is the relative decrease in the risk of an adverse event in the exposed group compared to an unexposed group. It is computed as (I_u - I_e) / I_u, where I_e is the incidence in the exposed group, and I_u is the incidence in the unexposed group. If the risk of an adverse event is increased by the exposure rather than decreased, the term relative risk increase (RRI) is used, and it is computed as (I_e - I_u)/I_u. If the direction of risk change is not assumed, the term relative effect is used, and it is computed in the same way as relative risk increase. Numerical examples Risk reduction Risk increase See also * Population Impact Measures * Vaccine efficacy Vaccine efficacy or vaccine effectiveness is the percentage reduction of disease cases in a vaccinated group of people compared to an unvaccinated group. For example, a vaccine efficacy or effectiveness of 80% indicates an 80% decrease in the ... Ref ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Attributable Fraction Among The Exposed
In epidemiology, attributable fraction among the exposed (AFe) is the proportion of incidents in the exposed group that are attributable to the risk factor. The term attributable risk percent among the exposed is used if the fraction is expressed as a percentage. It is calculated as AF_e = (I_e - I_u)/I_e = (RR - 1) / RR, where I_e is the incidence in the exposed group, I_u is the incidence in the unexposed group, and RR is the relative risk. It is used when an exposure increases the risk, as opposed to reducing it, in which case its symmetrical notion is preventable fraction among the unexposed. Synonyms Multiple synonyms of AFe are in use: attributable fraction, relative attributable risk, attributable proportion among the exposed, and attributable risk among the exposed. Similarly, attributable risk percent (ARP) is used as a synonym for the attributable risk percent among the exposed. In climatology, fraction of attributable risk (FAR) is used to denote a proportion of ad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Population Impact Measures
Population impact measures (PIMs) are biostatistical measures of risk and benefit used in epidemiological and public health research. They are used to describe the impact of health risks and benefits in a population, to inform health policy. Frequently used measures of risk and benefit identified by Jerkel, Katz and Elmore, describe measures of risk difference (attributable risk), rate difference (often expressed as the odds ratio or relative risk), population attributable risk (PAR), and the relative risk reduction, which can be recalculated into a measure of ''absolute benefit'', called the number needed to treat. Population impact measures are an extension of these statistics, as they are measures of absolute risk at the population level, which are calculations of number of people in the population who are at risk to be harmed, or who will benefit from public health interventions. They are measures of absolute risk and benefit, producing numbers of people who will benefit fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Preventable Fraction For The Population
In epidemiology, preventable fraction for the population (PFp), is the proportion of incidents in the population that could be prevented by exposing the whole population. It is calculated as PF_p = (I_p - I_e)/I_p, where I_e is the incidence in the exposed group, I_p is the incidence in the population. It is used when an exposure reduces the risk, as opposed to increasing it, in which case its symmetrical notion is attributable fraction for the population. See also * Population Impact Measures * Preventable fraction among the unexposed In epidemiology, preventable fraction among the unexposed (PFu), is the proportion of incidents in the unexposed group that could be prevented by exposure. It is calculated as PF_u = (I_u - I_e)/I_u = 1 - RR, where I_e is the incidence in the expose ... References Epidemiology Medical statistics {{health-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epidemiology
Epidemiology is the study and analysis of the distribution (who, when, and where), patterns and determinants of health and disease conditions in a defined population. It is a cornerstone of public health, and shapes policy decisions and evidence-based practice by identifying risk factors for disease and targets for preventive healthcare. Epidemiologists help with study design, collection, and statistical analysis of data, amend interpretation and dissemination of results (including peer review and occasional systematic review). Epidemiology has helped develop methodology used in clinical research, public health studies, and, to a lesser extent, basic research in the biological sciences. Major areas of epidemiological study include disease causation, transmission, outbreak investigation, disease surveillance, environmental epidemiology, forensic epidemiology, occupational epidemiology, screening, biomonitoring, and comparisons of treatment effects such as in clinical trials. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
