Received a letter?

You may have received a letter from your GP informing you about this study.

EVIDENCE is a new way of comparing the safety and effectiveness of two very similar medications that are commonly used for high blood pressure. It works by assigning GP practices to follow a prescribing policy. Doctors in participating practices use the assigned policy to guide their prescribing choices and, where clinically appropriate, patients have their regular medications altered in-line with the policy. Routinely collected NHS data will be used to compare the safety and effectiveness of the medications so that, in future, doctors and patients have all the information they need to make the best treatment choices.

If you would like to know more about the EVIDENCE study, please email or call the EVIDENCE team on 0800 9173509.

Frequently Asked Questions

What happens if I get any problems?

We do not expect you will experience any problems with this change but if you are concerned at all about symptoms you think might be related to the change then please get in touch with the study team and we can discuss this with you. If you feel your problem is urgent please contact your usual GP.

I’ve received my letter - What do I need to do now?

You don’t have to take any action as the work will all have been done in your surgery. When you next request your repeat prescription in the usual way you will receive the correct medicine your practice has agreed to prescribe. If you are already on this medicine then nothing will change. If you need to be switched to the new tablet that will happen when you make the request for your repeat prescription.

The dose of my new medicine is different to my old medicine (e.g it was 1.5mg M/R and now 2.5mg)

The dose of your new medicine has been checked by your doctor/ pharmacist/ GP and is the equivalent dose to the previous medicine. If you have concerns you can call the EVIDENCE team from 9am – 5pm on 0800 9173509.

Why are you changing my tablets?

These are two medicines that doctors prescribe very widely for high blood pressure that both work in a very similar way. We are trying and find out which one if any is best. It will help doctors make the best choice of medicine in future. Everyone in your practice who has been prescribed one of these medicines for high blood pressure will be given the same medicine – this has been agreed by practice and is not specific to you.

Does my Doctor know about this?

Yes. This work is fully supported by your Doctor and your practice has agreed to prescribe one or other of the medicines. We are trying to minimise the workload on your GP surgery so would prefer it if you contacted us with any questions but please feel free to discuss with your practice if you prefer.

Need to get in touch?

By Post

MEMO Research, Level 7,
Ninewells Hospital and Medical School,
Dundee, UK,


By Phone

01382 383119
Monday to Friday
8.45am to 5.00pm


By Email
Or click here to use our contact form


For more detailed information about the study, please click the link below to open the Patient Information Sheet for this study. Please also feel free to visit the NHS "Changing Your Medication" and NICE guidelines links below. On those pages, you will find official NHS policy on changing existing prescriptions for taking part in studies, and the guidelines that we adhere to for this type of reasearch.

Evidence Logo
University of Dundee Logo
Memo Research Logo

The team
Here to help you

Angela Flynn

Study pharmacist responsible for implementing the study in GP practices. She also provides training for other pharmacists throughout Scotland.

Dr Alex Doney

Senior Clinical Lecturer at the University of Dundee and Honorary Consultant Physician at Ninewells Hospital with a specialist interest in Blood Pressure and Cardiovascular risk.

Lewis McConnachie

IT Lead for MEMO Research. Specialising in improving and streamlining interactions with GPs and GP system through novel use of technology.

Amy Rogers

Clinical Research Fellow focusing on large scale drug safety and effectiveness trials. Particular interests include pragmatic research methodologies and evidence based prescribing in primary care.

Rebecca Barr

Project Manager for MEMO Research. Experienced project manager of decentralised clinical trials.

Rob Flynn

Statistician and Superintendent Pharmacist he has worked on many large scale international studies and projects.

Shirley Freser

Study Administrator – including GP Practice Recruitment and Contracts.

Contact Us
Any questions?