Study using OpenSAFELY shows shielding policy reduced severe COVID-19 outcomes among clinically vulnerable people in England

A new study made possible by the Bennett Institute’s OpenSAFELY platform has found that the UK’s shielding policy – an intervention developed to support those most at risk of serious illness from COVID-19 – reduced hospitalisations and deaths among clinically vulnerable people in England during the first phase of the COVID-19 pandemic.

The research, led by the London School of Hygiene and Tropical Medicine (LSHTM) and funded by the Medical Research Foundation, provides new evidence on the impact of shielding during the COVID-19 pandemic, and highlights how similar measures could help mitigate future disease outbreaks.

The study was led by Rosalind Eggo, Professor of Infectious Disease Dynamics from the London School of Hygiene and Tropical Medicine (LSHTM).

Analysing the electronic health records of 24 million patients across England in OpenSAFELY, Professor Eggo and researchers at LSHTM found that 7,800-10,600 hospitalisations (25%), and 2,300-3,500 deaths (23%) were prevented by the UK’s shielding policy from 22 March-1 December 2020.

In the whole population - including shielding and non-shielding people - researchers found that 14,700-21,800 hospitalisations and 3,700-5,500 deaths were prevented by the shielding policy, each corresponding to reductions of 13%.

Professor Ben Goldacre, Director of the Bennett Institute for Applied Data Science, said:

We built the OpenSAFELY platform specifically to help researchers deliver lifesaving data analysis. This study is a testament to the power of NHS GP records. It proves that data platforms can be safe and transparent while also enabling great research. We are hugely grateful to patients and to all our collaborators including the teams at NHS England, universities across the country, the electronic health record suppliers TPP and EMIS, and our supporters at the Royal College of GPs and the British Medical Association.

Professor Seb Bacon, Chief Technology Officer for Bennett Institute for Applied Data Science, said:

From the outset, we were committed to building a data analytics platform that was transparent, trustworthy, efficient, and easy to use at scale. By keeping the data locked down but every aspect of every project open, OpenSAFELY sets the standard for openness, enabling researchers to use, understand, and reproduce publicly available code, and understand the real-world impact of clinical interventions.

To learn more about our work with big data, visit the Bennett Institute’s website, follow the Institute on LinkedIn and @bennettoxford.bsky.social (BlueSky), and sign up to receive notifications of the latest blog posts and newsletter updates.