Effect of information format on intentions and beliefs regarding diagnostic imaging for non-specific low back pain: A randomised controlled trial in members of the public.

Abstract

To evaluate the effects of information format on intentions to request diagnostic imaging for non-specific low back pain in members of the public. We performed a three arm, 1:1:1, superiority randomised trial on members of the public. Participants were randomised to one of the three groups: a Standard Care Leaflet group (standard information on low back pain), a Neutral Leaflet group (balanced information on the benefits and harms of imaging) and a Nudge Leaflet group (with behavioural cues to emphasise the harms of unnecessary imaging). Our primary outcome was intention to request imaging for low back pain. 418 participants were randomised. After reading the leaflet, intention to request imaging (measured on an 11-point scale (0 = definitely would not request to 10 = definitely would request) was lower in the Nudge Leaflet group (mean = 4.6, SD = 3.4) compared with the Standard Care Leaflet group (mean = 5.3, SD = 3.3) and the Neutral Leaflet group (mean = 5.3, SD = 3.0) (adjusted mean difference between Nudge and Neutral, -1.0 points, 95%CI -1.6 to -0.4). Framing information to emphasise potential harms from overdiagnosis reduced intention to request diagnostic imaging for low back pain. Nudge leaflets could help clinicians manage patient pressure for unnecessary tests.