How Can Clinicians Help Patients Make Decisions Consistent With Their Values?

Previous research shows clearly that, when presenting treatment options to patients, the type of statistic chosen to illustrate the risks and benefits of treatment may affect the patient's choice. For example, even when the actual data are equivalent, a patient is more likely to choose invasive therapy if the outcomes of treatment are presented in terms of likely survival as compared to the likely risk of dying. However, Carling and colleagues also wanted to understand these effects and how they related to an individual's values—which they define as the "relative importance of the desirable and undesirable effects of an intervention."

Both trials were carried out via the Internet, and were advertised on Norwegian television. On logging on to the study websites, information about the study was presented to participants and some details collected from them regarding baseline information and their values in relation to treatment. Participants were then randomized to different displays regarding the risks and benefits of different treatment options. One study randomized 2,978 participants who then viewed six alternative presentations of the likely reduction in risk of coronary heart disease after taking statins. The other trial randomized 1,760 people to four different displays (or no information) regarding the likely effects of antibiotics on sore throat.

Both trials show that as participants' values change, their decision as to whether to opt for (or seek) treatment also change. For example, in the statins trial, participants who are more concerned about the preventio n of coronary heart disease are more likely to choose to take statins. In addition, some ways of presenting information about risk were found to be more "persuasive" in motivating participants to opt for treatment, irrespective of their values. Overall, Carling and colleagues found that, in the statins trial, presenting risk as natural frequencies (whole numbers of people affected, per 100 population) were the best understood, gave participants most confidence in their decision, and were the most appropriate tool to use for presenting these type of data. In the "sore throat" trial, bar charts showing likely duration of symptoms were found to be similarly the most appropriate tool in helping participants make decisions consistent with their values.

The limitations of the studies include the fact that participants were more likely to be young and well-educated relative to the general population, and that the studies involved participants imagining their response in relation to two hypothetical scenarios, rather than actual decision making by patients. A previous pilot trial establishing the feasibility of carrying out this type of study over the Internet was published in PLoS One.

In this month's related editorial the PLoS Medicine editors question the nature and effects of shared decision making on patient care and subsequent treatment. The editors discuss the criteria for when shared decisions between patient and healthcare provider should be made, how different forms of data presentation can deepen a patient's understanding of possible treatment options, and how certain presentations can also prove unfairly persuasive. Linking to the two research articles by Cheryl Carling and colleagues, the editorial analyses the best ways for healthcare providers to be as informative as possible, whilst maintaining objectivity and a respect for patients' values prior to treatment.

Both studies were funded by the Norwegian Research Council.