hazard ratio and relative risk difference

This is the result you would get using the relative risk calculator, too. If we denoted the smokers who developed cancer with a, those who did not with b, the non-smokers who developed cancer with c and those who did not with d the formula and solution will look like so: Practical example: if we take smokers and risk of lung cancer as an example, if we know that from the exposed group (smokers) 25 developed some kind of lung cancer and 75 remained cancer free, while in the non-smokers 1 person developed lung cancer and 99 remained cancer-free, what is the relative risk of smokers versus non-smokers? This is what is computed by this risk ratio calculator.

developing a disease or condition, being injured, dying, etc.) in an exposed group to the probability of the event occurring in a comparison, non-exposed group: RR = P(event when exposed) / P(event when not exposed). Both express the ratio of the probability of an event occurring (e.g. The two are synonyms and denote the relative difference in risk between an exposed group and a control group, or a treatment group and a control group, depending on context. What is relative risk and what is a risk ratio? A two-sided confidence interval for NNT is also presented. The risk ratio calculator will output: relative risk, two-sided confidence interval, left-sided and right-sided confidence interval, one-sided p-value and z-score, the number needed to treat to achieve the benefit for a single person (NNT Benefit) or number of people that need to be exposed for one negative outcome to occur (NNT Harm). You can select any level of significance you require for the confidence intervals. disease and no disease) for each of the two groups. To use the tool you need to simply enter the number of events and non-events (e.g. This relative risk calculator allows you to perform a post-hoc statistical evaluation of a set of risk data when the outcome of interest is the change in relative risk (the risk ratio) or the absolute risk difference (ARR) between an exposed/treatment group and a control group. Standard error and confidence interval formula for risk ratios.What is a risk ratio confidence interval and 'confidence level'.Number Needed to Treat (NNT) for harm or benefit.Relative risk vs Odds Ratio vs Hazard Ratio.What is relative risk and what is a risk ratio?.

Hazard ratio and relative risk difference