Helpful Questions for Life in an Uncertain World

When it comes to results of medical tests and treatments, people have a need for certainty. However, often our most important decisions must be made under considerable uncertainty.

We've identified a couple of questions that can help you face uncertainty and facilitate your understanding of risks across different situations:

1. Risk of what?
Understand the outcome to which the risk refers. Is it the risk of dying from a disease, getting the disease, or manifesting a symptom?

2. What is the time frame?
Time frames such as "the next 10 years" are easier to imagine than the widely used "lifetime" risks. They are more informative because risks change over time, and yet such time frames are long enough to enable action.

3. How big is the risk?
Because there are no zero risks, size is what matters. That number should be expressed in absolute tems - for instance, 13 out of 1,000 50-year-old female smokers die of heart disease within 10 years - or in comparative terms, relating the risk to other ones. For example, a 50-year-old female smoker has about the same chance of dying of heart disease as of lung cancer within the next decade - and these chances are about seven times higher than her risk of perishing in a car accident.

4. Does the risk apply to me?
Find out if the risk is based on studies of people like you - individuals of your age or sex or with health problems similar to yours.

5. What are the harms of "finding out"?
Screening tests may lead to false alarms, prompting unnecessary anxiety. When women participate in a 10-year program of annual mammography, every other woman without cancer can expect one or more false-positive test results. Worse, screening tests often detect abnormalities that would never cause symptoms, leading to unnecessary surgery and other invasive treatments.