Communicating risk to patients and the public

Despite years of trying to communicate risk to patients and months of reading about it recently, I found this article confusing,¹ because it fails to address a fundamental question ‘what is the aim of communicating risk?’

The authors refer to two possible aims of communicating risk. The first is to facilitate a shared, evidence-based decision that ‘both Mrs Jones and her doctor may be satisfied about’. The second is ‘to promote risk reduction through behaviour change’. They do not mention the tension between these, but it has been discussed by several authors including Gupta;² some of those studying evidence-based decision-making, including Professor Edwards,³ state that the primary goal of any doctor–patient interaction is the facilitation of evidence-based choice, even where this leads the patient to decide not to follow medical advice, a stance supported in the NICE guidance on adherence.⁴ This tension seems widely ignored by those working to achieve behaviour change, who therefore advocate choosing the most ‘persuasive’ risk representation format. A clear example of the conflict between these aims lies in the controversy over decision aids for bowel cancer screening, where Bekker's ‘informed uptake’⁵ was Penston's ‘propaganda’.⁶

Naik et al imply that their first priority is ‘informed decision-making’ and a focus on ‘the individual patient’.¹ However, they describe improving adherence as crucial, without acknowledging any difficulty in reconciling this aim with their first one, and they refer predominantly to the behaviour change literature.

Without a defined aim, methods of communicating risk cannot be judged or ranked: the paper's references to effectiveness beg the question ‘what effect do we want?’ The Cochrane review of decision aids referred to, and its more recent update,⁷ looked at a wide range of assessable outcomes and concluded that there was some improvement in measures of decision quality, no effect on health outcomes or anxiety, and inconclusive evidence about adherence. A recent study by Gale et al illustrates this, finding that even a demonstrably successful health-literacy-promoting intervention about cardiovascular risk made no difference to whether or not subjects chose to take tablets,⁸ although many welcomed the increased involvement and informedness they gained.

The key question is whether, and how, people make use of risk information once they have understood it, and there is a growing body of evidence about this. In order to contribute to analysis of this evidence, a future paper on risk communication should begin with a debate about its aims.