Decision aids beneficial for people facing health treatment or screening decisions

Compared with usual care across a wide variety of decision contexts, people exposed to decision aids felt more knowledgeable (high-quality evidence), better informed (high-quality evidence) and clearer about their values. They probably had a more active role in decision making and more accurate risk perceptions (moderate-quality evidence). There were no adverse effects on health outcomes or satisfaction. There was improved knowledge and accurate risk perceptions when decision aids were used either within or in preparation for the consultation. Although knowledge scores and accurate risk perceptions were significantly higher in the decision-aid group compared with usual care, there was no difference in these outcomes when comparing decision aids used in preparation for, versus during, the consultation.