Enabling understanding must not lead to manipulation

Who would disagree that understanding risks in order to trade them off against potential benefits is a prerequisite for citizens or patients who need to make health decisions? But rational consideration of risk, even if graphically explained1 and understood, is neither straightforward nor sufficient. Rationality is not the only component in decision making.

Apparently irrational influences and considerations exert strong pressures. Individuals' perceptions of risk, and attitudes to it, may lead them to choices that seem irrational to the health professional. Perceptions are built up over time, informed by personal experiences and social networks, and shaped by behavioural norms and media reporting. Fear of a disease, trust in technology, and the desire to take responsibility for health also contribute to decisions people make.2

Research shows that avoidance of regret (that an intervention was freely available but was not taken up), a perceived right to access, and pursuit of equitability are reasons given by men for accepting and recommending …