Research Article: Effect of different visual presentations on the public’s comprehension of prognostic information using acute and chronic condition scenarios: two online randomised controlled trials
Abstract:
Objectives To assess the effectiveness of bar graph, pictograph and line graph compared with text-only, and to each other, for communicating prognosis to the public. Design Two online four-arm parallel-group randomised controlled trials. Statistical significance was set at p<0.016 to allow for three-primary comparisons. Participants and setting Two Australian samples were recruited from members registered at Dynata online survey company. In trial A: 470 participants were randomised to one of the four arms, 417 were included in the analysis. In trial B: 499 were randomised and 433 were analysed. Interventions In each trial four visual presentations were tested: bar graph, pictograph, line graph and text-only. Trial A communicated prognostic information about an acute condition (acute otitis media) and trial B about a chronic condition (lateral epicondylitis). Both conditions are typically managed in primary care where ‘wait and see’ is a legitimate option. Main outcome Comprehension of information (scored 0–6). Secondary outcomes Decision intention, presentation satisfaction and preferences. Results In both trials, the mean comprehension score was 3.7 for the text-only group. None of the visual presentations were superior to text-only. In trial A, the adjusted mean difference (MD) compared with text-only was: 0.19 (95% CI ?0.16 to 0.55) for bar graph, 0.4 (0.04 to 0.76) for pictograph and 0.06 (?0.32 to 0.44) for line graph. In trial B, the adjusted MD was: 0.1 (?0.27 to 0.47) for bar graph), 0.38 (0.01 to 0.74) for pictograph and 0.1 (?0.27 to 0.48) for line graph. Pairwise comparisons between the three graphs showed all were clinically equivalent (95% CIs between ?1.0 and 1.0). In both trials, bar graph was the most preferred presentation (chosen by 32.9% of trial A participants and 35.6% in trial B). Conclusions Any of the four visual presentations tested may be suitable to use when discussing quantitative prognostic information. Trial registration number Australian New Zealand Clinical Trials Registry (ACTRN12621001305819).
Introduction:
Providing patients with information on their health can encourage active participation in making decisions. 1 Having a conversation about prognosis can involve communicating quantitative data such as the likelihood of occurrence of an outcome, recurrence, or improvement over time, or the likely duration of the illness. Information about a condition’s natural history (ie, the natural course of the condition without treatment) is also encompassed under the umbrella of prognostic information. Understanding prognostic…
Read more