Along with its elected Health and Social Care Council, techUK was invited this afternoon to attend a briefing with NHSX Chief Technology Officer David Turner on the work that led to the decision to move to the Google-Apple decentralised model for the coronavirus tracing app.
The Department of Health and Social Care (DHSC) revealed earlier today that field tests building on the initial trial in the Isle of Wight had identified a number of technical challenges with the NHS' version of the app, including the reliability of detecting contacts on certain operating systems.
Field tests were used to validate how successful the tool is at detecting contact between people in various real-life scenarios, using a number of phones to test operating systems and devices and observing how the app performs in background and locked state.
Findings showed that Android detected over 70% of all contacts from Android/iOS phones in all instances. iOS detected up to 70% of contacts with the app running in foreground, and “significantly less” when in background.
During the past month, the NHS has been testing the app against the Google-Apple model. It found that their system registered 99% of both Android devices and iPhones, but their distance calculations were reportedly weaker.
As a result, Health and Social Care Secretary Matt Hancock said today the Government would join forces with Google and Apple to “bring the best bits of both systems together”.
“We will share our algorithm and the work done on distance calculations and combine that with their work to deliver a new solution,” Hancock said.
In a statement, the DHSC explained: “While it does not yet present a viable solution, at this stage an app based on the Google/Apple API appears most likely to address some of the specific limitations identified through our field testing. However, there is still more work to do on the Google/Apple solution which does not currently estimate distance in the way required.
“Based on this, the focus of work will shift from the current app design and to work instead with Google and Apple to understand how using their solution can meet the specific needs of the public.”
The UK is not the first country to make this switch, with Germany and Denmark also moving to the Google and Apple approach in recent weeks.