How doctors' language impacts peoples' understanding and decision making about cardiovascular risk

This experimental study seeks to investigate the effect of different labels for high blood pressure (hypertension vs high normal blood pressure) on treatment decision-making and psychosocial outcomes (perceived severity; level of concern), compared to a control group where no label is given. It will also explore whether any effect is affected by a) sharing absolute risk information and b) health literacy. The intervention will be delivered via an online survey to each participant which they can complete on any computer at their convenience during the study period. Website analytics will be used to monitor completion rates to monitor adherence to the study. Each participant will read a hypothetical diagnosis based on the group to which they have been randomised and complete a questionnaire based on this information (anticipated time to complete the survey is approximately 15minutes). Survey participants will be randomised into one of three groups receiving a different hypothetical diagnosis from a clinician, either the ‘hypertension label’ arm, ‘high normal blood pressure’ arm and a ‘control’ arm given no label. Within each arm of the study they will be randomised to one of two sub groups, receiving either an ‘absolute risk description’ or no further information. HYPERTENSION LABEL STUDY ARM HYPOTHETICAL You are at your doctor (GP) for a check-up. The doctor has taken your blood pressure a few times recently and says: Your blood pressure readings are 135/ 85 and that means you have hypertension. *Absolute risk description provided to half of the study arm through randomisation: Hypertension can increase your risk of heart disease. Combining your current blood pressure reading with your other risk factors means your overall risk of a heart attack or stroke in the next 10 years is low (that is, you have less than 10% risk of a heart attack or stroke) HIGH NORMAL BP LABEL STUDY ARM HYPOTHETICAL: You are at your doctor (GP) for a check-up. The doctor has taken your blood pressure a few times recently and says: Your blood pressure readings are 135/ 85 and that means you have high normal blood pressure. *Absolute risk description provided to half of the study arm through randomisation: High blood pressure can increase your risk of heart disease. Combining your current blood pressure reading with your other risk factors means your overall risk of a heart attack or stroke in the next 10 years is low (that is, you have less than 10% risk of a heart attack or stroke)