Structuring the presentation Structured presentations (especially with question and answer approaches) for presenting treatment options were well received and understood in work with patients and the public (DECIDE patients and public, Santesso et al. 2015). When summarising evidence on treatment options for patients and the public, a simple tabular format, as shown in figure 5, allows easy comparison and improves comprehension of treatment benefits and harms (DECIDE patients and public, Glenton et al. 2010, Loudon et al. 2014, Santesso et al. 2015, Santesso et al. 2016). ‘No treatment’ (doing nothing) should be considered and presented as an option to help people understand the benefits and risks of interventions. Presenting the benefits and harms for each option allows patients and the public to weigh these options against their personal values and preferences and can support conversations with healthcare professionals, something patients and the public have asked for (Santesso et al. 2016). It should be clear that information presented on the benefits and harms of treatment options is based on a systematic search and appraisal of the evidence. Figure 5 Example of presenting treatment options in SIGN’s patient version of mood disorders in pregnancy Using qualitative and quantitative statements about benefits and harms Existing patient versions in the English language generally say little about potential benefits and harms of treatment options, and very few provide numerical information (Santesso et al. 2016). There is evidence that people’s understanding of risk can be improved by presenting them with numbers rather than words and even when people say they prefer words, giving them both improves their understanding (Büchter et al. 2014, Knapp et al. 2014, Natter and Berry 2005). For numerical information, using absolute numbers, rather than relative numbers, and natural frequencies (for example, ‘50 of 100 people’) are easiest to understand and are less confusing (Büchter et al. 2014, DECIDE patients and public, Knapp et al. 2014, Natter and Berry 2005). Evidence shows that patients and consumers overestimate risks when probabilities are presented in verbal terms. Using numbers results in more accurate estimates of risk (Büchter et al. 2014, Knapp et al. 2014, Natter and Berry 2005, Santesso et al. 2015, Trevana et al. 2013). There is good evidence, that presenting relative risk reduction alone leads to overestimation of treatment effects, so this should be avoided (Trevena et al. 2013). Although there is currently no certain way to present numerical information from guidelines to patients and the public, we recommend guideline producers present information on benefits and harms and consider adding numerical information. Many people, although not all, would like to see such information on benefits and harms. Numerical information presented as a statement has been found to be more helpful than pictograms, but any numerical information should be tested with the target audience (Ottawa Hospital Research Institute 2020). For qualitative text statements, standard text such as that shown in figure 6 provides consistency and includes both the size of the effect (for example, will not decrease, will decrease, probably decreases, may decrease, will not lead to more side effects) and the certainty and quality of the evidence (Büchter et al. 2014, Knapp et al. 2014, Natter and Berry 2005, Santesso 2015). Figure 6 Format for presenting information from a Cochrane review of the effect of Vitamin C on the common cold in plain language (Hemillä et al. 2007) Information about benefits and harms should refer to patient-relevant outcomes. Reporting on benefits could include controlling or getting rid of symptoms, prevention of recurrence, and eliminating the condition both short term and long term. Reporting on risks could include side effects, complications and adverse reactions to treatment, both short term and long term. Note that the harms of an option extend beyond clinical risks. For example, to make a treatment choice between radiation therapy and brachytherapy for prostate cancer, it may be important for some people that one treatment is non-invasive and requires several sessions whereas the other is invasive and performed at a single session. If the effect of treatments on morbidity or mortality is unknown, this should be stated. Presenting uncertainty Patients and the public do want to know about uncertainty (Knapp et al. 2009). For example, how sure are we that X in 100 of those affected will have pain? This information can be understood if well presented. Most guideline producers will have a system to evaluate the quality or certainty of the evidence. Different systems such as symbols, words and letters may be used, and if not intuitive, it may be helpful to include a description of what the system means in the patient version. In addition, if reference is made to treatments for which there is no or very low quality research, this should be made clear. It should not be confused with a treatment in which evidence has shown that the treatment has little to no effect. Figure 7 is an example of how SIGN has presented such information. Figure 7 Example from SIGN on presenting information about a treatment which is not supported by the evidence Using graphical approaches to present information Focus groups and user testing with patients and the public found that patients and the public liked graphics to break up the text, but that graphics and charts should be kept simple (DECIDE patients and public). Those who used numerical information to increase their understanding of the risks and benefits indicated a preference for the information to be presented in pie charts. Evidence from a low-quality randomised controlled trial suggests that bars, pictographs and tables tend to be efficient tools to present numerical information (Trevena et al. 2013). The authors found that information seemed clearer when presented in this format. Simple bar charts were easily understood although they don’t convey uncertainty. Graphs should present benefits and harms on the same scale and alternative treatment options should be reported for the same outcomes.