Don't forget the basics
Web based risk calculators are among the newest information resources available to people who want to understand the health risks they face. The advantage of these calculators is their ability to generate tailored risk information based on personal factors. But their usefulness depends on their accuracy and whether they are complete or balanced. To focus on the second issue, we present a hypothetical case history highlighting some elements of good (and not so good) risk communication.
The case: Mr Jones is a 55 year old white man worried about prostate cancer after reading about a politician who had recently been diagnosed with the disease. His first search effort–using the Google search engine to look for “prostate cancer and risk calculator” yields 8410 hits. The first hit (http://www.yourcancerrisk.harvard.edu/) seems perfect. This asks him questions about himself and, based on his age, ethnic group, family history, height, vasectomy history (he had one), and dietary habits (he eats ext-link ≤5 servings of food with animal fat a day and ≤5 servings of tomato based foods a week), tells him his risk is above average. He is now even more worried and calls his doctor.
Mr Jones's doctor explains that three things are missing in this risk assessment: clarity about the risk, context, and an acknowledgment of uncertainty.
Clarity means knowing what specific risk is under consideration (is this about getting or dying …
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