Putting a figure on risk Flashcards
What is the difference between a risk and odds?
Risk is a proportion of probability/quantified uncertainty. Odd is is a ratio.
What is absolute risk?
An individual’s risk of developing disease over a period of time without reference to another group.
How to calculate absolute risk?
Number with risk/total group
How to calculate odds?
Number with outcome/ Number with outcome
How is absolute risk measured?
Risk from 0 to 1
What is absolute risk reduction?
Absolute difference in outcomes between the control and the group receiving treatment
What is risk difference?
Proportion which tells investigators how much risk will decrease if an intervention happens or exposure decreases.
How to calculate absolute risk reduction?
Control Event Rate - Experimental Event Rate
What is the Control Event rate?
Risk of adverse events in control group
What is the experimental event rate?
Risk of adverse event in experimental group
Why is the risk difference shown in absolute risk reduction beneficial?
Provides information about impact.
What does positive risk difference indicate?
Risk is higher in the control group.
What does negative risk difference indicate?
Risk is higher in the exposed group.
What is relative risk?
Comparing the risk for two groups against each other.
How to calculate relative risk?
The Risk in exposed group/ The risk in unexposed group.
What does risk ratio indicate?
Strength of relationship
How is odds ratio calculated?
Odds of disease in exposed group/ odds of disease in unexposed groups
What does odd ratio analysis mean?
Values less than 1 indicate risk is lower in exposed group. Values greater than 1 indicates risk is higher in the exposed group.
How to calculate relative risk reduction?
Control Event Rate- Experimental Event Rate/ Control Event Rate
How does informed shared decision making affect risks?
Makes people more likely to accept risks that voluntary, controllable, familiar, non-catastrophic and fair
Why is risk communication important?
For health promotion activities, encouraging informed clincial practise and informed shared decision making
How to communicate risk with patients?
Avoid descriptive terms, develop trust, decision aids and practise
