Using decision aids to support self-isolation during the COVID-19 pandemic.

Self-isolation is a vital element of efforts to contain COVID-19. We set out to test whether decision aids can support self-isolation. We conducted a pre-registered online experiment with a nationally representative sample (n = 500). Three stages tested: (i) whether decision trees help people to decide whether they need to self-isolate; (ii) whether an online planning tool increases people's confidence in their ability to self-isolate; and (iii) whether infographics help people to absorb advice on managing a household in which someone must self-isolate. (i) Accuracy of matching symptom patterns to a response scale for the need to self-isolate; (ii) self-reported confidence in coping with self-isolation; (iii) objective tests of recall and comprehension. Decision trees improved decisions about when self-isolation was necessary, although participants systematically underestimated the need to self-isolate with less common COVID-19 symptoms (e.g. sore throat, fatigue). The online planning tool increased confidence about coping with self-isolation only among the adults aged under 40. Infographics improved recall and comprehension of how to manage self-isolation. Decision aids can be used to support self-isolation during COVID-19. The study also demonstrates how even an emergency public health response can benefit from rapid experimental pre-testing of interventions.