BackgroundA shortage of organs available for transplantation is causing loss of life. Increasing the number of individuals on the National Health Service (NHS) Organ Donor Register (ODR) is one way to address the shortage of organs. In Great Britain, new drivers registering for their driving licence are invited to join the ODR. A further 17 million drivers renew their road tax online each year, presenting an additional opportunity to prompt drivers to join the ODR. This trial explores the effect of adding persuasive messages to a prompt to join the ODR at the end of road tax payment transactions.MethodsIn this pragmatic, parallel group, quasi-randomised controlled trial, drivers renewing their road tax or registering for a driving licence were alternately allocated, using a JavaScript randomisation code embedded in the GOV.UK website, to view a control prompt inviting sign-ups to the ODR or the same prompt plus one of seven theoretically informed persuasive messages; (i) social norms alone, (ii) social norms plus the NHS ODR logo, (iii) social norms plus an image, (iv) loss frame, (v) gain frame, (vi) reciprocity and (vii) cognitive dissonance. The trial took place over a 4-week period in June 2013. The primary outcome measure was participants completing the online registration form (sign-ups).ResultsAltogether, 1,085,322 website users were included in the study. Further, 1171 more sign-ups were completed under the most effective message (reciprocity) compared to the control prompt alone (reciprocity: n = 4256, control: n = 3085; odds ratio, OR 1.38, 95% confidence interval 1.32–1.45, p < 0.001). The loss-framed message was as effective. All messages increased sign-ups compared to the control prompt apart from the social norms message plus image (n = 2879; OR 0.94, 95% confidence interval 0.89–0.99, p < 0.05).ConclusionsShort persuasive messages alongside a prompt can persuade more ODR sign-ups for individuals renewing their road tax than a prompt alone. The most effective message remains in place today. Since the trial in 2013, the same message has been implemented across 25 government end-of-transaction websites on GOV.UK, resulting in 529,000 new registrations to the ODR up to 31st October 2017.Electronic supplementary materialThe online version of this article (10.1186/s13063-018-2855-5) contains supplementary material, which is available to authorized users.

Background and aims The UK low‐risk drinking guidelines (LRDG) recommend not regularly drinking more than 14 units of alcohol per week. We tested the effect of different pictorial representations of alcohol content, some with a health warning, on knowledge of the LRDG and understanding of how many drinks it equates to. Design Parallel randomized controlled trial. Setting On‐line, 25 January–1 February 2019. Participants Participants (n = 7516) were English, aged over 18 years and drink alcohol. Interventions The control group saw existing industry‐standard labels; six intervention groups saw designs based on: food labels (serving or serving and container), pictographs (servings or containers), pie charts (servings) or risk gradients. A total of 500 participants (~70 per condition) saw a health warning under the design. Measurements Primary outcomes: (i) knowledge: proportion who answered that the LRDG is 14 units; and (ii) understanding: how many servings/containers of beverages one can drink before reaching 14 units (10 questions, average distance from correct answer). Findings In the control group, 21.5% knew the LRDG; proportions were higher in intervention groups (all P < 0.001). The three best‐performing designs had the LRDG in a separate statement, beneath the pictograph container: 51.1% [adjusted odds ratio (aOR) = 3.74, 95% confidence interval (CI) = 3.08–4.54], pictograph serving 48.8% (aOR = 4.11, 95% CI = 3.39–4.99) and pie‐chart serving, 47.5% (aOR = 3.57, 95% CI = 2.93–4.34). Participants underestimated how many servings they could drink: control mean = −4.64, standard deviation (SD) = 3.43; intervention groups were more accurate (all P < 0.001), best performing was pictograph serving (mean = −0.93, SD = 3.43). Participants overestimated how many containers they could drink: control mean = 0.09, SD = 1.02; intervention groups overestimated even more (all P < 0.007), worst‐performing was food label serving (mean = 1.10, SD = 1.27). Participants judged the alcohol content of beers more accurately than wine or spirits. The inclusion of a health warning had no statistically significant effect on any measure. Conclusions Labels with enhanced pictorial representations of alcohol content improved knowledge and understanding of the UK's low‐risk drinking guidelines compared with industry‐standard labels; health warnings did not improve knowledge or understanding of low‐risk drinking guidelines. Designs that improved knowledge most had the low‐risk drinking guidelines in a separate statement located beneath the graphics.

Background Unsolicited feedback can solicit changes in prescribing. Objectives Determine whether a low-cost intervention increases clinicians’ engagement with data, and changes prescribing; with or without behavioural science techniques. Methods Randomized trial (ISRCTN86418238). The highest prescribing practices in England for broad-spectrum antibiotics were allocated to: feedback with behavioural impact optimization; plain feedback; or no intervention. Feedback was sent monthly for 3 months by letter, fax and email. Each included a link to a prescribing dashboard. The primary outcomes were dashboard usage and change in prescribing. Results A total of 1401 practices were randomized: 356 behavioural optimization, 347 plain feedback, and 698 control. For the primary engagement outcome, more intervention practices had their dashboards viewed compared with controls [65.7% versus 55.9%; RD 9.8%, 95% confidence intervals (CIs): 4.76% to 14.9%, P &lt; 0.001]. More plain feedback practices had their dashboard viewed than behavioural feedback practices (69.1% versus 62.4%); but not meeting the P &lt; 0.05 threshold (6.8%, 95% CI: −0.19% to 13.8%, P = 0.069). For the primary prescribing outcome, intervention practices possibly reduced broad-spectrum prescribing to a greater extent than controls (1.42% versus 1.12%); but again not meeting the P &lt; 0.05 threshold (coefficient −0.31%, CI: −0.7% to 0.1%, P = 0.104). The behavioural impact group reduced broad-spectrum prescribing to a greater extent than plain feedback practices (1.63% versus 1.20%; coefficient 0.41%, CI: 0.007% to 0.8%, P = 0.046). No harms were detected. Conclusions Unsolicited feedback increased practices’ engagement with data, with possible slightly reduced antibiotic prescribing (P = 0.104). Behavioural science techniques gave greater prescribing effects. The modest effects on prescribing may reflect saturation from similar initiatives on antibiotic prescribing. Clinical Trial Registration ISRCTN86418238.

Objectives: To compare the impact of appearance versus healthframed messages on engagement in a brief web-based risk screening and alcohol reduction intervention. Design: Randomised trial delivered via Drinkaware's website. Visitors were exposed to appearance (n ¼ 51,588) or health-framed messages (n ¼ 52,639) directing them towards an AUDIT-C risk screening questionnaire. Users completing this questionnaire were given feedback on their risk level and extended frame-congruent information. Outcomes: The primary outcome is completion of the AUDIT-C questionnaire. The secondary outcome is whether the participant accessed any of four further resources. Results: The appearance-framed message led to a small but significant increase in the number of users completing the AUDIT-C compared to the health-framed message (n ¼ 3,537, 6.86% versus n ¼ 3,355, 6.37%, p < 0.01). Conversely, following subsequent risk feedback, users exposed to extended health-framed information were more likely to access further resources (n ¼ 1,146, 2.17% versus n ¼ 942, 1.83%, p < 0.01). Conclusions: Physical appearance-framed messages increased the likelihood of engagement with an online alcohol screening and brief intervention tool, whereas health-framed messages increased the likelihood of accessing further resources. This highlights the potential for the use of multi-level approaches in alcohol reduction interventions.