Guidelines recommend that decision aids (DAs) provide quantitative information about the risks and benefits of available health care options. For screening tests, this includes absolute risk, risk reduction, and frequency of complications. But there is uncertainty whether such data is helpful to all patients, especially for those with low numeracy. No well-powered randomized trial has measured the impact of disclosing the recommended types of quantitative information, and previous studies have not examined whether patients find such data to be essential for their decision-making.
