At the moment many research studies are mostly reliant on data recorded about patients when they are admitted to hospital. While this data tells us quite a lot about many health problems, it doesn’t allow us to see the whole picture.

For example, around one-third of strokes are not identified in hospital admissions data as patients may be treated through different settings, such as in outpatient clinics.

When you look at diabetes the problem is even bigger with only one-in-three cases being picked up in hospital admissions data. Incomplete data will reduce the ability of scientific studies to produce robust results.

There are three ways in which safe and secure access to GP data would benefit public health research.

First, clinical trials would be easier to do and produce more reliable results. Currently, many trials require trial participants to provide medical information to researchers, then for the researchers to input the data in the trial systems and then the trial team have to go back to manually check the data against the medical records.

This is labour intensive, expensive and increases the burden on the healthcare staff and participants. Taking part in a clinical trial can result in a big demand on participants’ time, especially if it involves travelling to research sites to provide health information or filling out lengthy questionnaires.

Having access to participants’ GP data will help us to reduce that burden on the participants as well as opening up trials to people who would be unable to take part for logistical reasons, such as lack of transport to take them to a research site, living too far away from where a trial is taking place, or work commitments.

GP Data for Planning and Research will mean that, with their consent, researchers will be able to access the medical records of participants and monitor their health before, during and after the clinical trial they are taking part in.

For example, the RECOVERY trial is testing treatments given to patients while they are in hospital with COVID-19, but GP data will allow us to find out the effects of these treatments on long-term health problems, such the development of lung or kidney disease or symptoms of ‘long-COVID’.

With more data we can run more trials and on a bigger scale, potentially delivering results faster and getting effective treatments rolled out quicker.

Second, research into the causes of poor health would be better and more reliable. To understand the causes of disease, researchers often need to observe a large group or ‘cohort’ of people over many years to see whether people with a particular characteristic, such as smoking, higher blood pressure or overweight, have a higher risk of developing particular conditions.

Controlled access to GP Data for Planning and Research will allow the researchers to find out about the causes of common and important conditions that are often treated by GPs like dementia, asthma and depression. Studies like this can often be done without the researchers needing to identify anyone in the data.

Third, researchers could study how treatments are delivered by GPs and find out more about the barriers to accessing care. For example, at the University of Oxford we published a study showing that around 3500 fewer people started treatment for colorectal cancer between April and October 2020 than was expected based on numbers from 2019.

However, we couldn’t tell why - it could have been because people were not contacting their GP about symptoms or because the GPs were not referring patients for assessment.

If we had timely access to GP Data for Planning and Research, then we could have found out why people with cancer weren’t being diagnosed and enabled the NHS to take action to make sure everyone receives the best care they can.

Data is very important to us as researchers to allow us to do our jobs, but we also understand that people are concerned about how it is used and so there are stringent rules in place to protect everyone’s confidentiality.

Researchers go through a rigorous application process to access healthcare data from NHS Digital or other national data custodians. We need to demonstrate the benefit that having access to this data will have on patients and the public and sign a legally binding contract about what we can and can’t do with the data. We can be audited to make sure that we are using and handling the data exactly as we promised.

All patients should have the right to determine what happens to their data and if they don’t want them to be used for research they can opt out. But if many people opt out, or scientists are prevented from securely accessing GP data for healthcare research, then it will reduce the strength of our research, hindering advances in public health both now and in the future.