Effects of Message framing and Time discounting on heath communication for Optimum Cardiovascular disease and Stroke Prevention（EMT-OCSP）is a pragmatic, 2 × 2 factorial, randomized, controlled, observer blinded, multicenter trial with four parallel groups. It aims to determine if risk and intervention communication strategy（gain-framed versus loss-frame, long-term context versus short-term context and the potential interaction）have different effect on optimizing adherence to clinical preventive management （in the endpoint of CVD risk reduction）for subjects with at least one moldable risk factor for CVD.

Scientific title Effects of Message framing and Time discounting on health communication for Optimum Cardiovascular disease and Stroke Prevention(EMT-OCSP): a pragmatic randomised controlled study

Principal Investigator Li He

Study period 2020-07-01-2022-01-21

Hypotheses and aims When communicating cardiovascular disease（CVD）risk to individuals, different presentation of information carries its own connotations and biases. The one or the other pattern of the presentation may affect individuals' decision making.This study aims to determine if risk and intervention communication strategy（gain-framed versus loss-frame, long-term context versus short-term context and the potential interaction）have different effect on optimizing adherence to clinical preventive management （in the endpoint of CVD risk reduction）for subjects with at least one moldable risk factor for CVD. We aim to provide evidence for practitioners regarding messaging strategies that improve communication effectiveness and further reduce the risk of CVD events in the population, as well as to develop more effective communication strategies for groups of people with different characteristics to maximise patient adherence to lifestyle modifications and medical treatment.

Primary outcome Ten-year CVD risk, lifetime CVD risk and CVD-free life expectancy after 1 year according to the LIFE-CVD model.

Secondary outcomes CVD risk factors [blood pressure(BP) and serum cholesterol, low-density lipoprotein (LDL), non-high-density lipoprotein (HDL), triglycerides and fasting glucose levels],lifestyle factors (physical activity, tobacco use, alcohol use and eating habits), pharmacological treatments for hypertension, dyslipidaemia and diabetes, and anti-thrombotic drug prescriptions after 1 year.

Study design The EMT-OCSP trial is designed as a pragmatic, 2 × 2 factorial, randomized, controlled, observer blinded, multicenter trial with four parallel groups. Randomization will be performed as block randomization with a 1:1:1:1 allocation.

Study population and sample size Subjects with at least one moldable risk factor for CVD. The sample size calculations revealed that the enrolment of 15,000 participants would be sufficient, allowing for a 20% drop-out rate.

Follow-up period One year

Inclusion Criteria:

• aged 45-80 years,
• personally own and use a smartphone (Apple or Android platform) with Internet access,
• and have at least one of the following CVD risk factors: history of CVD at age < 60 years in a first-degree relative, smoking, diabetes, hypertension, and low-density lipoprotein (LDL)cholesterol ≥ 4.5 mmol/L.

Exclusion Criteria:

• participants with histories of CVD, heart failure, or chronic kidney disease (estimated glomerular filtration rate < 30 mL/min/1.73m2);
• those with terminal malignancy at baseline;
• those with severe psychological or mental disorders
• violation of the study protocol and participation in another clinical study during follow-up

Researchers affiliated with the EMT-OCSP study will have access to an internal webpage listing available aggregated datasets and variables; they will not have access to individual data or the original database.External researchers collaborating with at least one steering group member may submit standardised applications for data via this webpage.Upon steering group approval, the data manager will export anonymised aggregated data to authorised researchers.

6 months after publication