Under what conditions is the OR a good approximation of the RR?

Under what conditions is the OR a good approximation of the RR?

In case-control studies, and in cohort studies in which the outcome occurs in less than 10% of the unexposed population, the OR provides a reasonable approximation of the RR.

What is the difference between RR and HR?

Hazard ratios differ from relative risks (RRs) and odds ratios (ORs) in that RRs and ORs are cumulative over an entire study, using a defined endpoint, while HRs represent instantaneous risk over the study time period, or some subset thereof.

Is incidence rate ratio the same as relative risk?

The incidence rate is defined as number of events divided by the person-time at risk. The ratio between two cumulative incidences (risk in exposed divided by risk in unexposed) gives the relative risk (or risk ratio).

What is the difference between RR and OR?

The odds ratio (OR) is the ratio of odds of an event in one group versus the odds of the event in the other group. An RR (or OR) more than 1.0 indicates an increase in risk (or odds) among the exposed compared to the unexposed, whereas a RR (or OR) <1.0 indicates a decrease in risk (or odds) in the exposed group.

When would you use a case control study?

When is a Case-Control Study Desirable?

1. When the disease or outcome being studied is rare.
2. When the disease or outcome has a long induction and latent period (i.e., a long time between exposure and the eventual causal manifestation of disease).
3. When exposure data is difficult or expensive to obtain.

How do I find my RR?

Relative risk is calculated by dividing the death or disease risk in a specific population group (Group A) by the risk of people from all other groups. A relative risk that is greater than 1.0 shows that there is an increased risk among the people in Group A.

What’s a bad heart rate?

You should visit your doctor if your heart rate is consistently above 100 beats per minute or below 60 beats per minute (and you’re not an athlete).

How do you interpret incidence rate?

Incidence risk is the total number of new cases divided by the population at risk at the beginning of the observation period. For example, if one hundred sow farms were followed for a year, and during this time 10 sow farms broke with a disease, then the incidence risk for that disease was 0.1 or 10%.

How is RR calculated?

What does the RR of 1.4 indicate?

A relative risk or odds ratio greater than one indicates an exposure to be harmful, while a value less than one indicates a protective effect. RR = 1.2 means exposed people are 20% more likely to be diseased, RR = 1.4 means 40% more likely. OR = 1.2 means that the odds of disease is 20% higher in exposed people.