A streamlined pathway for transcatheter aortic valve implantation: the BENCHMARK study.

BACKGROUND AND AIMS: There is significant potential to streamline the clinical pathway for patients undergoing transcatheter aortic valve implantation (TAVI). The purpose of this study was to evaluate the effect of implementing BENCHMARK best practices on the efficiency and safety of TAVI in 28 sites in 7 European countries. METHODS: This was a study of patients with severe symptomatic aortic stenosis (AS) undergoing TAVI with balloon-expandable valves before and after implementation of BENCHMARK best practices. Principal objectives were to reduce hospital length of stay (LoS) and duration of intensive care stay. Secondary objective was to document patient safety. RESULTS: Between January 2020 and March 2023, 897 patients were documented prior to and 1491 patients after the implementation of BENCHMARK practices. Patient characteristics were consistent with a known older TAVI population and only minor differences. Mean LoS was reduced from 7.7 ± 7.0 to 5.8 ± 5.6 days (median 6 vs. 4 days; P < .001). Duration of intensive care was reduced from 1.8 to 1.3 days (median 1.1 vs. 0.9 days; P < .001). Adoption of peri-procedure best practices led to increased use of local anaesthesia (96.1% vs. 84.3%; P < .001) and decreased procedure (median 47 vs. 60 min; P < .001) and intervention times (85 vs. 95 min; P < .001). Thirty-day patient safety did not appear to be compromised with no differences in all-cause mortality (0.6% in both groups combined), stroke/transient ischaemic attack (1.4%), life-threatening bleeding (1.3%), stage 2/3 acute kidney injury (0.7%), and valve-related readmission (1.2%). CONCLUSIONS: Broad implementation of BENCHMARK practices contributes to improving efficiency of TAVI pathway reducing LoS and costs without compromising patient safety.

Quality of Life Measures in Aortic Stenosis Research: A Narrative Review.

BACKGROUND: Elderly patients with aortic stenosis (AS) not only have a reduced life expectancy but also a reduced quality of life (QoL). The benefits of an AS intervention may be considered a balance between a good QoL and a reasonably extended life. However, the different questionnaires being used to determine the QoL were generally not developed for the specific situation of patients with AS and come with strengths and considerable weaknesses. The objective of this article was to provide an overview of the available QoL instruments in AS research, describe their strengths and weaknesses, and provide our assessment of the utility of the available scoring instruments for QoL measurements in AS. SUMMARY: We identified and reviewed the following instruments that are used in AS research: Short Form Health Survey (SF-36/SF-12), EuroQol-5D (EQ-5D), the Illness Intrusiveness Rating Scale (IIRS), the HeartQoL, the Kansas City Cardiomyopathy Questionnaire (KCCQ), the Minnesota Living with Heart Failure Questionnaire (MLHF), the MacNew Questionnaire, and the Toronto Aortic Stenosis Quality of Life Questionnaire (TASQ). KEY MESSAGES: There is no standardized assessment of QoL in patients with AS. Many different questionnaires are being used, but they are rarely specific for AS. There is a need for AS-specific research into the QoL of patients as life prolongation may compete for an improved QoL in this elderly patient group.

Participant engagement with a short, wordless, animated video on COVID-19 prevention: a multi-site randomized trial.

COVID-19 misinformation has spread rapidly across social media. To counter misinformation, we designed a short, wordless and animated video (called the CoVideo) to deliver scientifically informed and emotionally compelling information about preventive COVID-19 behaviours. After 15 163 online participants were recruited from Germany, Mexico, Spain, the UK and the USA, we offered participants in the attention placebo control (APC) and do-nothing arms the option to watch the CoVideo (without additional compensation) as post-trial access to treatment. The objective of our study was to evaluate participant engagement by quantifying (i) the proportion of participants opting to watch the CoVideo and (ii) the duration of time spent watching the CoVideo. We quantified the CoVideo opt-in and view time by experimental arm, age, gender, educational status, country of residence and COVID-19 prevention knowledge. Overall engagement with the CoVideo was high: 72% of the participants [CI: 71.1%; 73.0%] opted to watch the CoVideo with an average view time of 138.9 out of 144.0 s [CI: 138.4; 139.4], with no statistically significant differences by arm. Older participants (35-59 years) and participants with higher COVID-19 prevention knowledge had higher view times than their counterparts. Spanish participants had the highest opt-in percentage whereas Germans exhibited the shortest view times of the five countries. Short, wordless and animated storytelling videos, optimized for 'viral spread' on social media, can enhance global engagement with COVID-19 prevention messages by transcending cultural, language and literary barriers.

Reactance to Social Authority in a Sugar Reduction Informational Video: Web-Based Randomized Controlled Trial of 4013 Participants.

BACKGROUND: Short and animated story-based (SAS) videos can be an effective strategy for promoting health messages. However, health promotion strategies often motivate the rejection of health messages, a phenomenon known as reactance. In this study, we examine whether the child narrator of a SAS video (perceived as nonthreatening, with low social authority) minimizes reactance to a health message about the consumption of added sugars. OBJECTIVE: This study aims to determine whether our SAS intervention video attenuates reactance to the sugar message when compared with a content placebo video (a health message about sunscreen) and a placebo video (a nonhealth message about earthquakes) and determine if the child narrator is more effective at reducing reactance to the sugar message when compared with the mother narrator (equivalent social authority to target audience) or family physician narrator (high social authority) of the same SAS video. METHODS: This is a web-based randomized controlled trial comparing an intervention video about sugar reduction narrated by a child, the child's mother, or the family physician with a content placebo video about sunscreen use and a placebo video about earthquakes. The primary end points are differences in the antecedents to reactance (proneness to reactance, threat level of the message), its components (anger and negative cognition), and outcomes (source appraisal and attitude). We performed analysis of variance on data collected (N=4013) from participants aged 18 to 59 years who speak English and reside in the United Kingdom. RESULTS: Between December 9 and December 11, 2020, we recruited 38.62% (1550/4013) men, 60.85% (2442/4013) women, and 0.52% (21/4013) others for our study. We found a strong causal relationship between the persuasiveness of the content promoted by the videos and the components of reactance. Compared with the placebo (mean 1.56, SD 0.63) and content placebo (mean 1.76, SD 0.69) videos, the intervention videos (mean 1.99, SD 0.83) aroused higher levels of reactance to the message content (P<.001). We found no evidence that the child narrator (mean 1.99, SD 0.87) attenuated reactance to the sugar reduction message when compared with the physician (mean 1.95, SD 0.79; P=.77) and mother (mean 2.03, SD 0.83; P=.93). In addition, the physician was perceived as more qualified, reliable, and having more expertise than the child (P<.001) and mother (P<.001) narrators. CONCLUSIONS: Although children may be perceived as nonthreatening messengers, we found no evidence that a child narrator attenuated reactance to a SAS video about sugar consumption when compared with a physician. Furthermore, our intervention videos, with well-intended goals toward audience health awareness, aroused higher levels of reactance when compared with the placebo videos. Our results highlight the challenges in developing effective interventions to promote persuasive health messages. TRIAL REGISTRATION: German Clinical Trials Registry DRKS00022340; https://tinyurl.com/mr8dfena. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.2196/25343.

Evaluating the impact of short animated videos on COVID-19 vaccine hesitancy: An online randomized controlled trial.

Addressing the global challenge of vaccine hesitancy, amplified during the COVID-19 pandemic due to misinformation propagated via social media, necessitates innovative health communication strategies. This investigation scrutinizes the efficacy of Short, Animated, Story-based (SAS) videos in fostering knowledge, behavioral intent, and engagement around COVID-19 vaccination. We conducted an online three-arm parallel randomized controlled trial (RCT) involving 792 adult participants (≥18 years, English-speaking) from the United States. The intervention group viewed a SAS video on COVID-19 vaccination, the attention placebo control group watched a SAS video on hope, and the control group received no intervention. Our primary objectives were to assess the influence of SAS videos on knowledge, behavioral intent, and engagement regarding COVID-19 vaccination. Participants in the intervention group displayed significantly higher mean knowledge scores (20.6, 95 % CI: 20.3-20.9) compared to both the attention placebo control (18.8, 95 % CI: 18.5-19.1, P < .001) and control groups (18.7, 95 % CI: 18.4-19.0, P < .001). However, SAS videos did not notably affect behavioral intent. Perception of COVID-19 as a significant health threat emerged as a strong predictor for engaging with the post-trial video without further incentives (OR: 0.44; 95 % CI: 0.2-0.96). The 35-44 age group exhibited the highest post-trial engagement (P = .006), whereas right-wing political inclination negatively associated with engagement (OR: 1.98; 95 % CI: 3.9-1.01). Vaccination status correlated significantly with self-efficacy (P < .001), perceived social norms (P < .001), and perceived response efficacy of the COVID-19 vaccine (P < .001), all heightened in the intervention group. These findings suggest that while SAS videos effectively amplify COVID-19 vaccination knowledge, their impact on behavioral intent is not direct. They do, however, affect determinants of vaccination status, thereby indirectly influencing vaccination behavior. The study highlights the appeal of SAS videos among younger audiences, but underscores the need for further examination of factors impeding vaccination engagement. As SAS videos closely mirror conventional social media content, they hold significant potential as a public health communication tool on these platforms. Trial Registration: Trial was registered at drks.de with the identifier DRKS00027938, on 5 January 2022.

Modifiable risk factors for permanent pacemaker after transcatheter aortic valve implantation: CONDUCT registry.

OBJECTIVE: The onset of new conduction abnormalities requiring permanent pacemaker implantation (PPI) after transcatheter aortic valve implantation (TAVI) is still a relevant adverse event. The main objective of this registry was to identify modifiable procedural risk factors for an improved outcome (lower rate of PPI) after TAVI in patients at high risk of PPI. METHODS: Patients from four European centres receiving a balloon-expandable TAVI (Edwards SAPIEN 3/3 Ultra) and considered at high risk of PPI (pre-existing conduction disturbance, heavily calcified left ventricular outflow tract or short membranous septum) were prospectively enrolled into registry. RESULTS: A total of 300 patients were included: 42 (14.0%) required PPI after TAVI and 258 (86.0%) did not. Patients with PPI had a longer intensive care unit plus intermediate care stay (65.7 vs 16.3 hours, p<0.001), general ward care stay (6.9 vs 5.3 days, p=0.004) and later discharge (8.6 vs 5.0 days, p<0.001). Of the baseline variables, only pre-existing right bundle branch block at baseline (OR 6.8, 95% CI 2.5 to 18.1) was significantly associated with PPI in the multivariable analysis. Among procedure-related variables, oversizing had the highest impact on the rate of PPI: higher than manufacturer-recommended sizing, mean area oversizing as well as the use of the 29 mm valve (OR 3.4, 95% CI 1.4 to 8.5, p=0.008) all were significantly associated with PPI. Rates were higher with the SAPIEN 3 (16.1%) vs SAPIEN 3 Ultra (8.5%), although not statistically significant but potentially associated with valve sizing. Implantation depth and postdelivery balloon dilatation also tended to affect PPI rates but without a statistical significance. CONCLUSION: Valve oversizing is a strong procedure-related risk factor for PPI following TAVI. The clinical impact of the valve type (SAPIEN 3), implantation depth, and postdelivery balloon dilatation did not reach significance and may reflect already refined procedures in the participating centres, giving attention to these avoidable risk factors. TRIAL REGISTRATION NUMBER: NCT03497611.

Subannular repair in secondary mitral regurgitation with restricted leaflet motion during systole.

OBJECTIVE: Ventricular secondary mitral regurgitation (SMR) (Carpentier type IIIb) results from left ventricular (LV) remodelling, displacement of papillary muscles and tethering of mitral leaflets. The most appropriate treatment approach remains controversial. We aimed to assess the safety and efficacy of standardised relocation of both papillary muscles (subannular repair) at 1-year follow-up (FU). METHODS: REFORM-MR (Reform-Mitral Regurgitation) is a prospective, multicentre registry that enrolled consecutive patients with ventricular SMR (Carpentier type IIIb) undergoing standardised subannular mitral valve (MV) repair in combination with annuloplasty at five sites in Germany. Here, we report survival, freedom from recurrence of MR >2+, freedom from major adverse cardiac and cerebrovascular events (MACCEs), including cardiovascular death, myocardial infarction, stroke, MV reintervention and echocardiographic parameters of residual leaflet tethering at 1-year FU. RESULTS: A total of 94 patients (69.1% male) with a mean age of 65.1±9.7 years met the inclusion criteria. Advanced LV dysfunction (mean left ventricular ejection fraction 36.4±10.5%) and severe LV dilatation (mean left ventricular end-diastolic diameter 61.0±9.3 mm) resulted in severe mitral leaflet tethering (mean tenting height 10.6±3.0 mm) and an elevated mean EURO Score II of 4.8±4.6 prior to surgery. Subannular repair was successfully performed in all patients, without operative mortality or complications. One-year survival was 95.5%. At 12 months, a durable reduction of mitral leaflet tethering resulted in a low rate (4.2%) of recurrent MR >2+. In addition to a significant improvement in New York Heart Association (NYHA) class (22.4% patients in NYHA III/IV vs 64.5% patients at baseline, p<0.001), freedom from MACCE was observed in 91.1% of patients. CONCLUSIONS: Our study demonstrates the safety and feasibility of standardised subannular repair to treat ventricular SMR (Carpentier type IIIb) in a multicentre setting. By addressing mitral leaflet tethering, papillary muscle relocation results in very satisfactory 1-year outcomes and has the potential to durably restore MV geometry; nevertheless, long-term FU is mandatory. TRIAL REGISTRATION NUMBER: NCT03470155.

Effects of side-effect risk framing strategies on COVID-19 vaccine intentions: a randomized controlled trial.

Background: Fear over side-effects is one of the main drivers of COVID-19 vaccine hesitancy. A large literature in the behavioral and communication sciences finds that how risks are framed and presented to individuals affects their judgments of its severity. However, it remains unknown whether such framing changes can affect COVID-19 vaccine behavior and be deployed as policy solutions to reduce hesitancy. Methods: We conducted a pre-registered randomized controlled trial among 8998 participants in the United States and the United Kingdom to examine the effects of different ways of framing and presenting vaccine side-effects on individuals' willingness to get vaccinated and their perceptions of vaccine safety. Results: Adding a descriptive risk label ('very low risk') next to the numerical side-effect and providing a comparison to motor-vehicle mortality increased participants' willingness to take the COVID-19 vaccine by 3.0 percentage points (p=0.003) and 2.4 percentage points (p=0.049), respectively. These effects were independent and additive and combining both framing strategies increased willingness to receive the vaccine by 6.1 percentage points (p<0.001). Mechanistically, we find evidence that these framing effects operate by increasing individuals' perceptions of how safe the vaccine is. Conclusions: Low-cost side-effect framing strategies can meaningfully affect vaccine intentions at a population level. Funding: Heidelberg Institute of Global Health. Clinical trial number: German Clinical Trials Registry (#DRKS00025551).

Vaccination is one of the main strategies for controlling the COVID-19 pandemic. But vaccination rates have slowed and are below target levels in countries like the United States and the United Kingdom. While there are many causes of vaccine hesitancy, several studies have found that fear of side effects is the one of the most important. Although COVID-19 vaccine side-effects are rare, how the media presents these risks may amplify concerns. Addressing public concerns over vaccine side effects is key to improving the uptake of vaccines and booster doses, which has been even lower than primary vaccine series uptake. Studies show that how risk is presented affects people's risk perceptions and behavior. To learn more about how COVID-19 vaccine risk framing affects risk perception, Sudharsanan et al. enrolled 8,998 people from the United States and the United Kingdom in an online randomized controlled trial. Participants received information about a hypothetical new COVID-19 vaccine, including its side effect rate, and reported their perception of safety and whether they would take the vaccine. The experiments showed that adding the label "very low risk" when describing vaccine side effect rates increased the number of people who said they would take the vaccine by three percentage points. Comparing the risks of the hypothetical vaccine to the much higher chances of motor vehicle deaths increased an individual's willingness to take the vaccine by 2.4 percentage points. Combining both framing strategies increased people's desire to get vaccinated by 6.1 percentage points. Deploying these two strategies in vaccine risk communications may help increase primary and booster vaccinations against COVID-19. A next step would be to measure both vaccination intentions and vaccination rates to confirm these strategies.

Participant Engagement and Reactance to a Short, Animated Video About Added Sugars: Web-based Randomized Controlled Trial.

BACKGROUND: Short, animated story-based (SAS) videos are a novel and promising strategy for promoting health behaviors. To gain traction as an effective health communication tool, SAS videos must demonstrate their potential to engage a diverse and global audience. In this study, we evaluate engagement with a SAS video about the consumption of added sugars, which is narrated by a child (a nonthreatening character), a mother (a neutral layperson), or a physician (a medical expert). OBJECTIVE: This study aims to (1) assess whether engagement with the sugar intervention video differs by narrator type (child, mother, physician) and trait proneness to reactance and (2) assess whether the demographic characteristics of the participants (age, gender, education status) are associated with different engagement profiles with the sugar intervention video. METHODS: In December 2020, after 4013 participants from the United Kingdom completed our randomized controlled trial, we offered participants assigned to the placebo arms (n=1591, 39.65%) the choice to watch the sugar intervention video (without additional compensation) as posttrial access to treatment. We measured engagement as the time that participants chose to watch the 3.42-minute video and collected data on age, gender, education status, and trait reactance proneness. Using ordinary least squares regression, we quantified the association of the demographic characteristics and trait reactance proneness with the sugar video view time. RESULTS: Overall, 66.43% (n=1047) of the 1576 participants in the 2 placebo arms voluntarily watched the sugar intervention video. The mean view time was 116.35 (52.4%) of 222 seconds. Results show that view times did not differ by narrator (child, mother, physician) and that older participants (aged 25-59 years, mean = 125.2 seconds) watched the sugar video longer than younger adults (aged 18-25 years, mean = 83.4 seconds). View time remained consistent across education levels. Participants with low trait reactance (mean = 119.3 seconds) watched the intervention video longer than high-trait-reactance participants (mean = 95.3 seconds), although this association did not differ by narrator type. CONCLUSIONS: The majority of participants in our study voluntarily watched more than half of the sugar intervention video, which is a promising finding. Our results suggest that SAS videos may need to be shorter than 2 minutes to engage people who are young or have high trait proneness to reactance. We also found that the choice of narrator (child, mother, or physician) for our video did not significantly affect participant engagement. Future videos, aimed at reaching diverse audiences, could be customized for different age groups, where appropriate. TRIAL REGISTRATION: German Clinical Trials Register DRKS00022340; https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00022340. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.2196/25343.

The effect of a short, animated story-based video on COVID-19 vaccine hesitancy: A study protocol for an online randomized controlled trial.

Introduction: Exposure to a high volume of vaccine misinformation on social media can have a negative effect on vaccine confidence and rates. To counteract misinformation, we designed a collage of three short, animated story-based (SAS) videos to convey scientifically informed and accessible information about COVID-19 vaccine applicable to a social media context. Methods and analysis: We will conduct an online randomized controlled trial primarily to: (1) determine the effectiveness of SAS videos in improving COVID-19 vaccine knowledge; (2) evaluate the effectiveness of SAS videos in increasing behavioral intent for COVID-19 vaccination; and (3) quantify people's interest in watching SAS videos about the COVID-19 vaccine. We also aim to identify barriers and facilitators to COIVD-19 vaccinations that have been shown to minimize vaccine hesitancy between vaccinated and unvaccinated populations. Using a web-based recruitment platform, a total of 10,000 adults from the United States will be recruited and randomly assigned to (1) a SAS video collage arm, (2) an attention placebo control video arm, or (3) no intervention arm (1:1:1). Furthermore, we will measure behavioral intent to obtain information on vaccination regarding COVID-19. At the end of the trial, participants randomized to arm 2 and arm 3 will be given the option of watching one of the intervention videos voluntarily to assess participant engagement with SAS videos. Finally, we will assess individual factors associated with vaccine hesitancy - hope, optimism, COVID-19 perceived risks and benefits, self-efficacy, perceived social norms, and trust - and compare vaccinated and unvaccinated participants across the three arms. Discussions: Evidence-based information from official channels can be complex and inaccessible to the general public, whereas false information on social media is frequently shared in brief postings, images, or videos that can easily reach the general public, thereby rapidly disseminating (mis-)information. To avoid the spread of misinformation, social media may be used to deliver evidence-based and emotionally compelling information in a readily accessible format in order to pre-empt misinformation. Our findings may help inform future SAS efforts addressing COVID-19 and other important public health challenges. Ethics and dissemination: The study was approved by the Heidelberg University Hospital's Ethics Committee (S-163/2022). The trial was registered with German Clinical Trials Register (www.drks.de) on 5 January 2022: number DRKS00027938. Findings of the study will be published in peer-reviewed scientific publications and possibly presented at scientific conferences.

Subannular repair for functional mitral regurgitation with reduced systolic ventricle function: rationale and design of REFORM-MR registry.

BACKGROUND: Functional mitral regurgitation (FMR) is one of the most common heart valve diseases that is a sequel of left ventricular remodelling. Although mitral valve annuloplasty is a standard treatment of FMR, the recurrence of FMR is a major drawback and occurs in 10-50% of patients. The REFORM-MR registry aims to investigate the effectiveness of standardized papillary muscle relocation and ring annuloplasty and to identify the risk factors associated with recurrent FMR. METHODS: REFORM-MR is a prospective, multicenter registry that enrols consecutive FMR patients across five sites in Germany. All patients with FMR and restricted movement of leaflets during systole (i.e., type IIIb mitral regurgitation) undergoing standardized subannular repair in combination with mitral valve annuloplasty are included in the study. The primary objective is to examine the effect of combined papillary muscle relocation and ring annuloplasty on the recurrence of FMR at 2 years postoperatively. The secondary objectives are MACCE rate, reinterventions on the mitral valve and cardiac-related mortality in the study cohort. Echocardiography core-lab and MRI core-lab will provide anonymized analysis of the imaging data in the REFORM-MR registry. Student's t-test or Mann-Whitney U test for continuous variables and the Chi-Square or Fisher exact test for categorical variables are used for group comparisons. Kaplan-Meier analyses is performed for survival and safety outcomes. RESULTS: As of May 2021, a total of 97 patients were enrolled across five sites in Germany. CONCLUSIONS: The results of this study will help define the outcomes of combined papillary muscle relocation and ring annuloplasty in the FMR treatment in a multicentre setting and to improve the understanding of the limitations of subannular repair procedures while treating patients with type III FMR. Trial registration clinicaltrials.gov Identifier: NCT03470155.

The effect of framing and communicating COVID-19 vaccine side-effect risks on vaccine intentions for adults in the UK and the USA: A structured summary of a study protocol for a randomized controlled trial.

OBJECTIVES: Vaccine hesitancy is a major hurdle for stopping the COVID-19 pandemic. Recently, fear of vaccine side effects created widespread concern and paused global vaccination efforts. Many studies find that how medical risks are framed and communicated can influence individuals' perceptions and behavior, yet there is little evidence on how the communication of COVID-19 vaccine side-effect risks influences vaccine intentions. The primary objective of our study is to evaluate how the framing of vaccine-side effect risks impacts individuals' vaccine intentions and perceptions of vaccine safety. The study will assess the impact of 3 dimensions of side-effect framing: 1. Qualitative risk labels: Determine whether attaching a qualitative risk label (e.g. adding "very low risk" next to the actual numerical risk) impacts individuals' willingness to take a vaccine and their perceptions of its safety. 2. Comparison groups: Determine how framing side-effect risks in comparison to other causes of mortality (COVID-19 mortality and motor vehicle mortality) impacts individuals' willingness to take a vaccine and their perceptions of its safety. 3. How the comparison risks are presented: Determine whether comparisons to other causes of mortality are presented on an absolute or relative scale impacts individuals' willingness to take a vaccine and their perceptions of its safety. Secondarily, we will also randomize a subset of individuals to receive the "status-quo" framing, where the vaccine side-effect risks are presented like how they were presented in the media. We will then compare vaccine intentions and perceptions of vaccine safety between the status-quo and the pooled intervention group samples to provide some insight into how "harmful" the status-quo framing was. Ultimately, we believe that our results will provide the some of the first experimental evidence on how the communication of COVID-19 vaccine risks may impact the public's willingness to be vaccinated and can inform future efforts to increase vaccination rates. TRIAL DESIGN: Our study is an online-based randomized controlled trial designed to evaluate the effect of different vaccine side-effect framings on COVID-19 vaccine intentions and perceived safety for a hypothetical COVID-19 vaccine. Using a factorial design, we will experimentally assess the impact of 3 risk framing strategies, varying whether the risk is presented: (1) with a qualitative label, (2) whether the risk is presented with a comparison risk, and (3) for comparison cases, whether the comparison is in absolute or relative terms. We will also randomize a portion of respondents to a status quo framing where the side effect risk mimics the media's communication in early April 2021. PARTICIPANTS: This will be an online study setting. We will use Prolific to recruit participants and host our study on the Gorilla platform. To be eligible, participants must be 18 years old or over (male, female, or other), have current residence in the US or UK, and be able to speak English. Participants will be excluded from the study if they do not meet our inclusion criteria. INTERVENTION AND COMPARATOR: Our study content will consist of five pages presented to individuals online. Page 1 will explain the purpose of the study and contain the consent information. Page 2 will contain basic sociodemographic questions, including participants' age, sex, and schooling level. Page 3 will set up the experiment by telling individuals that we will describe a hypothetical new COVID-19 vaccine and that we would like to know how likely they would be to take the vaccine and how safe they think the vaccine is. On this page, we will also encourage individuals to respond truthfully and remind them that their answers are confidential and cannot be linked back to any personal identifying information. Page 4 will be the main experimental slide, where we will present individuals with information on the vaccine, varying how the vaccination risk is communicated based on which experimental framing arm they are randomized to. We will factorially randomize across the following factors in the following order (separately by country). First, we will determine whether individuals are randomized to the status quo framing, or the intervention framings (1500 respondents to the status quo, and 4500 to the intervention). Among those randomized to the intervention framing, we will randomize (equal allocation) whether the side effect is presented without a comparison, with a comparison to COVID-19 mortality, or with a comparison to motor vehicle mortality. We will then factorially randomize (equal allocation) whether the risk is presented with a qualitative risk label or not (e.g. "very low risk"). To ensure that the factors are independent of one another, we will do this by randomizing individuals to the risk labels within strata of the comparison group factor. Lastly, among those randomized to the comparison group, we will factorially randomize whether the risk is presented as an absolute or relative comparison. As previously, we will ensure independence by doing this randomization within strata of comparison group*risk labelling. This entire design is visualized in the full protocol. The experimental text for each arm is: Arm 1: With regards to side effects, so far 8 individuals have developed potentially life-threatening blood clots. This is among the approximately 7 million adults that have received the vaccine so far. Arm 2: With regards to side effects, 1 out of 100,000 vaccinated individuals may develop serious blood clots. Arm 3: With regards to side effects, 1 out of 100,000 vaccinated individuals may develop serious blood clots (very low risk). Arm 4: Text for USA participants: With regards to side effects, 1 out of 100,000 vaccinated individuals may develop serious blood clots. As a reference, 170 out of every 100,000 unvaccinated Americans died of COVID-19 based on data from the past year. Text for UK participants: With regards to side effects, 1 out of 100,000 vaccinated individuals may develop serious blood clots. As a reference, 108 out of every 100,000 unvaccinated individuals in the UK died of COVID-19 based on data from the past year. Arm 5: Text for USA participants: With regards to side effects, 1 out of 100,000 vaccinated individuals may develop serious blood clots. As a reference, this is 1/170th of the risk of COVID-19 mortality among unvaccinated Americans based on data from the past year. Text for UK participants: With regards to side effects, 1 out of 100,000 vaccinated individuals may develop serious blood clots. As a reference, this is 1/108th of the risk of COVID-19 mortality among unvaccinated individuals in the UK based on data from the past year. Arm 6: Text for USA participants: With regards to side effects, 1 out of 100,000 vaccinated individuals may develop serious blood clots (very low risk). As a reference, 170 out of every 100,000 unvaccinated Americans died of COVID-19 based on data from the past year. Text for UK participants: With regards to side effects, 1 out of 100,000 vaccinated individuals may develop serious blood clots (very low risk). As a reference, 108 out of every 100,000 unvaccinated individuals in the UK died of COVID-19 based on data from the past year. Arm 7: Text for USA participants: With regards to side effects, 1 out of 100,000 vaccinated individuals may develop serious blood clots (very low risk). As a reference, this is 1/170th of the risk of COVID-19 mortality among unvaccinated Americans based on data from the past year. Text for UK participants: With regards to side effects, 1 out of 100,000 vaccinated individuals may develop serious blood clots (very low risk). As a reference, this is 1/108th of the risk of COVID-19 mortality among unvaccinated individuals in the UK based on data from the past year. Arm 8: Text for USA participants: With regards to side effects, 1 out of 100,000 vaccinated individuals may develop serious blood clots. As a reference, 12 out of every 100,000 Americans died in a motor vehicle accident based on data from the past year. Text for UK participants: With regards to side effects, 1 out of 100,000 vaccinated individuals may develop serious blood clots. As a reference, 2.6 out of every 100,000 individuals in the UK died in a motor vehicle accident based on data from the past year. Arm 9: Text for USA participants: With regards to side effects, 1 out of 100,000 vaccinated individuals may develop serious blood clots. As a reference, this is 1/12th of the risk of dying in a motor vehicle accident based on data from the past year. Text for UK participants: With regards to side effects, 1 out of 100,000 vaccinated individuals may develop serious blood clots. As a reference, this is almost 1/4th of the risk of dying in a motor vehicle accident based on data from the past year. Arm 10: Text for USA participants: With regards to side effects, 1 out of 100,000 vaccinated individuals may develop serious blood clots (very low risk). As a reference, 12 out of every 100,000 Americans died in a motor vehicle accident based on data from the past year. Text for UK participants: With regards to side effects, 1 out of 100,000 vaccinated individuals may develop serious blood clots (very low risk). As a reference, 2.6 out of every 100,000 individuals in the UK died in a motor vehicle accident based on data from the past year. Arm 11: Text for USA participants: With regards to side effects, 1 out of 100,000 vaccinated individuals may develop serious blood clots (very low risk). As a reference, this is 1/12th of the risk of dying in a motor vehicle accident based on data from the past year. Text for UK participants: With regards to side effects, 1 out of 100,000 vaccinated individuals may develop serious blood clots (very low risk). As a reference, this is nearly 1/4th of the risk of dying in a motor vehicle accidentbased on data from the past year. The risk information will be presented on a single page along with the two main outcome questions. Lastly, for individuals that reported that they are unlikely or unsure about whether they would take the vaccine, the final page will ask them their reason (question based on a recently published study of COVID-19 vaccine hesitancy). MAIN OUTCOMES: Our primary outcome is individuals' willingness to take the hypothetical COVID-19 vaccine. We will measure this outcome by asking, "How likely would you be to take this vaccine?" allowing individuals to choose from a four-point Likert response of "Unlikely, Unsure leaning towards unlikely, Unsure leaning towards likely, Very likely." This outcome variable, including the categories and phrasing, is based on a recently published study on COVID-19 vaccine hesitancy conducted by researchers with the Vaccine Hesitance Project at the London School of Hygiene and Tropical Medicine. Our secondary outcome is individuals' perceived safety of the vaccine. We will assess this outcome by asking individuals, "How safe do you feel this vaccine is?" allowing them to choose answers ranging from 1-10 where 1 is extremely unsafe, and 10 is extremely safe. Both outcomes will be measured at the time of the questionnaire. Participants can take up to 45 min to complete the questions but will not be able to go back and change their responses after submitting their questionnaire. RANDOMIZATION: Using a web-based randomization algorithm, Gorilla will randomly allocate participants to each of the experimental arms. Gorilla allows for two randomization options - independent randomization of each individual based on a probability draw and balanced randomization, which randomizes without replacement such that among groups of respondents a fixed proportion will end up in each experimental arm. We will use the "balanced randomization" option to ensure that our experimental arms are balanced. Participants will be randomized based on the allocations described above. BLINDING: Because Prolific handles the interaction between the study investigators and participants, the participants will be completely anonymous to the study investigators. The outcome measures will be self-reported and submitted anonymously. All persons in the study team will be blinded to the group allocation. NUMBERS TO BE RANDOMIZED: We will randomize 6000 participants per country for a total sample of 12000 individuals. TRIAL STATUS: The protocol version number is 1.0 and the date is July 14, 2021. Recruitment is expected to begin on 26 July 2021 and end by August 10, 2021. TRIAL REGISTRATION: The study and its outcomes were registered at the German Clinical Trials Register ( www.drks.de ) on July 12th, 2021: # DRKS00025551 . FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Full_Protocol_20Jul2021) In the interest of expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.

Effect of a story-based, animated video to reduce added sugar consumption: A web-based randomized controlled trial.

BACKGROUND: Short and animated story-based (SAS) videos, which can be rapidly distributed through social media channels, are a novel and promising strategy for promoting health behaviors. In this study, we evaluate the effectiveness of a SAS video intervention to reduce the consumption of added sugars. METHODS: In December 2020, we randomized 4159 English-speaking participants from the United Kingdom (1:1:1) to a sugar intervention video, a content placebo video about sunscreen use (no sugar message), or a placebo video about earthquakes (no health or sugar message). We nested six list experiments in each arm and randomized participants (1:1) to a control list or a control list plus an item about consuming added sugars. The primary end-points were mean differences (on a scale of 0-100) in behavioral intent and direct restoration of freedom to consume added sugars. RESULTS: Participants (N = 4013) who watched the sugar video had significantly higher behavioral intent to cut their daily intake of added sugar (mean difference (md) = 16.7, 95% confidence interval (CI) = 1.5-31.8, P = 0.031), eat fresh fruit daily (md = 16.7, 95% CI = 0.5-32.9, P = 0.043), and check food labels for sugar content (md = 20.5, 95% CI = 2.6-38.5, P = 0.025) when compared with the sunscreen (content placebo) video. The sugar video did not arouse intent to restore freedom and consume added sugars when compared with the two placebo videos. CONCLUSIONS: Our SAS intervention video did not arouse reactance and increased short-term behavioral intent among participants to reduce their consumption of added sugars. SAS videos, which draw on best practices from the entertainment-education media, communication theory, and the animation industry, can be an effective strategy for delivering emotionally compelling narratives to promote health behavior change. TRIAL REGISTRATION: German Clinical Trials Register: DRKS00022340.

The Effect of a Wordless, Animated, Social Media Video Intervention on COVID-19 Prevention: Online Randomized Controlled Trial.

BACKGROUND: Innovative approaches to the dissemination of evidence-based COVID-19 health messages are urgently needed to counter social media misinformation about the pandemic. To this end, we designed a short, wordless, animated global health communication video (the CoVideo), which was rapidly distributed through social media channels to an international audience. OBJECTIVE: The objectives of this study were to (1) establish the CoVideo's effectiveness in improving COVID-19 prevention knowledge, and (2) establish the CoVideo's effectiveness in increasing behavioral intent toward COVID-19 prevention. METHODS: In May and June 2020, we enrolled 15,163 online participants from the United States, Mexico, the United Kingdom, Germany, and Spain. We randomized participants to (1) the CoVideo arm, (2) an attention placebo control (APC) arm, and (3) a do-nothing arm, and presented 18 knowledge questions about preventive COVID-19 behaviors, which was our first primary endpoint. To measure behavioral intent, our second primary endpoint, we randomized participants in each arm to five list experiments. RESULTS: Globally, the video intervention was viewed 1.2 million times within the first 10 days of its release and more than 15 million times within the first 4 months. Knowledge in the CoVideo arm was significantly higher (mean 16.95, 95% CI 16.91-16.99) than in the do-nothing (mean 16.86, 95% CI 16.83-16.90; P<.001) arm. We observed high baseline levels of behavioral intent to perform many of the preventive behaviors featured in the video intervention. We were only able to detect a statistically significant impact of the CoVideo on one of the five preventive behaviors. CONCLUSIONS: Despite high baseline levels, the intervention was effective at boosting knowledge of COVID-19 prevention. We were only able to capture a measurable change in behavioral intent toward one of the five COVID-19 preventive behaviors examined in this study. The global reach of this health communication intervention and the high voluntary engagement of trial participants highlight several innovative features that could inform the design and dissemination of public health messages. Short, wordless, animated videos, distributed by health authorities via social media, may be an effective pathway for rapid global health communication during health crises. TRIAL REGISTRATION: German Clinical Trials Register DRKS00021582; https://tinyurl.com/6r4zkbbn. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.1186/s13063-020-04942-7.

Reactance to Social Authority in Entertainment-Education Media: Protocol for a Web-Based Randomized Controlled Trial.

BACKGROUND: Entertainment-education media can be an effective strategy for influencing health behaviors. To improve entertainment-education effectiveness, we seek to investigate whether the social authority of a person delivering a health message arouses the motivation to reject that message-a phenomenon known as reactance. OBJECTIVE: In this study, using a short animated video, we aim to measure reactance to a sugar reduction message narrated by a child (low social authority), the child's mother (equivalent social authority to the target audience), and a family physician (high social authority). The aims of the study are to determine the effect of the narrator's perceived social authority on reactance to the sugar reduction message, establish the effectiveness of the video in improving behavioral intent to reduce the intake of added sugars, and quantify participants' interest in watching the entertainment-education intervention video. METHODS: This is a parallel group, randomized controlled trial comparing an intervention video narrated by a low, equivalent, or high social authority against a content placebo video and a placebo video. Using a web-based recruitment platform, we plan to enroll 4000 participants aged between 18 and 59 years who speak English and reside in the United Kingdom. The primary end points will include measures of the antecedents to reactance (proneness to reactance and threat level of the message), its components (anger and negative cognition), and attitudinal and behavioral intent toward sugar intake. We will measure behavioral intent using list experiments. Participants randomized to the placebo videos will be given a choice to watch one of the sugar-intervention videos at the end of the study to assess participant engagement with the entertainment-education video. RESULTS: The study was approved by the ethics committee of Heidelberg University on March 18, 2020 (S-088/2020). Participant recruitment and data collection were completed in December 2020. The data analysis was completed in April 2021, and the final results are planned to be published by August 2021. CONCLUSIONS: In this trial, we will use several randomization procedures, list experimentation methods, and new web-based technologies to investigate the effect of perceived social authority on reactance to a message about reducing sugar intake. Our results will inform the design of future entertainment-education videos for public health promotion needs. TRIAL REGISTRATION: German Clinical Trials Registry DRKS00022340: https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00022340. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/25343.