Ethical clinical practice requires good communication about the risks of treatment causing harm. As health professionals and patients often have different perceptions of risk, it is important to discuss risk in terms the patient can understand. Even if a patient is willing to take the risks, health professionals have an ethical obligation not to recommend inappropriately risky treatments. Giving patients time to reflect on what a particular decision means for them is an important part of communicating information about risks.

Whenever a doctor recommends a course of therapy it is essential that the reasoning underlying this advice is discussed with the patient, together with an outline of potential risks, benefits and maybe alternatives. This is not merely because free choice is important but also because it is a part of the doctor's role within the clinical encounter to help patients learn about the nature, consequences and courses of their illnesses and to facilitate reflection about the personal meanings attached to them.

Clinical communication is complex, generally finely balanced, with both style and content requiring constant adjustment in relation to contextual and personal variables. The concept of 'risk', and the way it is used in the clinic, is complex, with the word having several possible meanings and many connotations. Significant discrepancies often exist between patients' and clinicians' use of the word risk. While for doctors, a risk may be defined in precise, mathematical terms - for example, as the probability of the occurrence of a particular adverse event - how such a definition is interpreted by a patient in the clinical setting can be highly variable.1,2

A complication in discussions of risk is that people make decisions for reasons that are not always entirely rational. They accept risks as a routine part of work, recreational and sporting activities. Many people are prepared to take complementary medicines in the absence of evidence of safety or efficacy, and the limited success of public health campaigns against alcohol and tobacco use emphasises that avoiding risk is not the sole criterion guiding people's decisions about their health. Even when risks are clearly recognised the implications are not straightforward. For example, the female sex partners of injecting drug users with good knowledge about HIV risk often continue to engage in risky behaviour.3

Extensive research has provided useful information that can assist in the development of effective communication about risk. For example, common perceptions of risk are based on both objective considerations and subjective judgements. 1 While objective considerations are important for the analysis of probabilities and consequences, subjective judgements determine the interpretations individuals place on these calculations in their own personal lives.

Good communication always requires an appreciation of the values of each participant in the discussion. Social science research has repeatedly emphasised that individual perceptions of risk may be affected by personal factors, which may be linked to values.4,5These include:

  • demographic factors such as age and gender
  • education and early experiences
  • the nature of the risk, its consequences and alternatives
  • portrayal of risk in the media and popular culture
  • the availability of information
  • the degree of personal trust in the regulatory authorities.6,7

For example, women are more likely to perceive greater risk than men in the use of alcohol and other drugs8, and education may lead either to increased or decreased concern with risk. Demographic factors and difficulties in understanding information may influence a patient's decision to participate in medical research.9 Personality and psychological characteristics are also of great importance.10

An 'optimistic bias' is often expressed with respect to health risks.11,12The risks are often underestimated by those who take them, both in specific areas, such as HIV and drug taking13,and more generally.14 Accordingly, the responsibility of a doctor does not cease with the approval or acquiescence of the patient. Rather, regardless of the patient's views, the clinician has an obligation not to embark on or recommend reckless or inappropriately hazardous treatments. This means that recommendations must be able to be supported by evidence, or at least strong arguments.

The quality and quantity of available evidence can vary, clinical contexts themselves are extremely diverse, and evidence from large-scale clinical trials may have limited applicability to specific conditions. It has become commonplace to refer to the notion of a 'risk: benefit ratio', which weighs beneficial outcomes against potential harms. This concept15 for the most part has little rigorous content or validity, since perceptions of risk vary according to context, and the perception of benefits also varies.

There are no algorithms to guarantee adequate communication. Factual information is important, but is not in itself sufficient. Formalised definitions of risk, such as those of the International Commission on Radiological Protection16 (which defined risk as the probability of a harmful outcome such as lethal cancer)and the tendency to insist on stereotyped formulations to explain the meanings of probabilities by drawing comparisons with common experiences (like driving a certain distance in a motor car) do not necessarily enhance communication. Nor do they help individuals to make sense of risk in their own particular contexts. Similarly, rigid policies or strategies about communication of risk aimed at achieving predetermined outcomes are likely to be ineffective. Neither purely factual campaigns nor those based on fear can reliably change people's behaviour.9,10

Clinicians should assist patients to reflect upon the possible personal consequences of a proposed course of action and to make sense of the information provided in relation to their own personal value systems. Communication of risk must be tailored to the needs and levels of understanding of individual patients. Both the circumstances and the content of communication are important. Privacy and an unhurried, secure setting may be critical. The use of words is important, with ordinary use of language being preferred over technical jargon wherever possible. Different patients will have different requirements regarding standards of proof of risk, safety and benefit and will arrive at different conclusions. Part of the everyday responsibility of the doctor is to respond with openness and flexibility to such differences.

In summary, communication about risk in medicine is a multifaceted process. Objective criteria, factual data, and ongoing research are essential, but need to be supplemented with an awareness of the broader, ethical context within which the clinical process is framed.

Further Reading

Lloyd AJ. The extent of patients' understanding of the risk of treatments. Qual Health Care 2001;10 Suppl 1:i14-8.

Conflict of interest: none declared

This article is the final one in a three-part series on risk. See also


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