Research has shown that some things can increase or decrease the likelihood of getting breast cancer. These are called 'risk factors'. But we are all different, so risk factors will not affect us all in the same way. One person may have many risk factors and not develop breast cancer, while another may have very few and be diagnosed with it.
Risk is the chance of something happening. There are a number of ways in which risk is represented. Risk is commonly talked about in two ways – absolute risk and relative risk.
Absolute risk: the actual chances (odds) of something happening over a period of time. It’s not compared to anything; it’s just the likelihood of something occurring. Absolute risk is often reported as a figure such as 1 in 8 (12%).
Relative risk: compares risk between different populations to show the likelihood of something increasing or reducing a particular risk, for example the risk of lung cancer in people who smoke compared to non-smokers. Relative risk doesn’t explain your actual risk. Relative risk is often reported as a percentage reduction of the absolute risk.
Sometimes it can be difficult to figure out what a risk means to an individual person in real terms.