Last week, with very little warning – even to those of us working in general practice – along came GP at Hand. Private doctor provider Babylon caused shockwaves with its offer to sign up patients from across London to its online GP service as a replacement for their regular NHS practices, with plans to expand to the rest of England. GP at Hand promises that patients will be able to “book an appointment within seconds” via its smartphone app and have a video consultation with a GP typically within under two hours of booking “anytime, anywhere”. Those who need it can then see a GP face to face within 48 hours at one of six sites across London.

On the surface, GP at Hand sounds wonderful – the NHS finally embracing technological advances in IT, offering almost immediate access when some are waiting three weeks for a non-urgent GP appointment. But while anyone can join its service, the website says it may not be suitable for “complex mental health problems or complex physical, psychological or social needs”. Or if you’re pregnant or older and frail, and as long as you don’t have dementia or learning difficulties or safeguarding issues. This new service is cherry-picking its target population.

This is worse than just failing to provide equal access; it undermines the basis on which GP practices achieve financial stability. We get paid an average of £151.37 a year for each registered patient, regardless of age or health and no matter how many times they are seen. We cannot refuse to register patients or advise them to register elsewhere based on age, gender or disability. If my surgery put a list on its website telling the most ill people in our catchment area we weren’t suitable for them, NHS England would serve us a breach of contract notice and could close us down.

The NHS is a social insurance system, where funding attached to the 80% of patients within a GP practice who are comparatively well pays for the 20% who are sick. Each time a patient registers with GP at Hand they become deregistered from their current practice, and the funding goes with them. By delivering care disproportionately to the worried well, GP at Hand undermines healthcare delivery to those who need it most. We will all eventually get to be in that 20%.

My own practice in Tower Hamlets, east London, is directly affected, as two of the six GP at Hand sites are within a couple of miles of us. We are already only just managing to maintain a service to those who are really ill; if we lose our fit and healthy patients we will struggle to continue caring for those who need us most.

There is general understanding among GP practices that our services need to move with the times, and already progress has been made, with online appointments booking, online prescriptions ordering and online access to our medical records. In my area we piloted eConsult, where patients can access, via their practice website, a variety of relevant services, including a symptom checker, a self-help page, signposting to a pharmacy, and pointers to the NHS 111 phoneline – or they can send an eConsult to their own GP, which will be answered in 48 hours.

But where is the evidence that these electronic innovations are improving access, giving better health outcomes, using resources better and saving public money? Do they meet the NHS’s underlying principal, one the nation buys into each election – of equality of care based on clinical need? Online access potentially disadvantages those patients without a computer, often the elderly, or those with poor IT skills, learning difficulties or English as a second language, introducing inequality that gives the advantage to more affluent and articulate patients.

Our preliminary experience with eConsult in our diverse east London population has not been good. Younger, generally healthier people use the technology often to get a medical opinion on minor illnesses that will get better in a few days. This might be acceptable if it freed up the GP’s time for sicker patients, but the emails need to be answered, and paradoxically add to the workload, instead of reducing it. GPs are paid for the services they provide, and the creeping coercion to offer electronic consultations inevitably diverts resources away from the care of sicker patients.

Online tools, evaluated by rigorous clinical trials, can transform general practice for the better, but equality of care based on clinical need must be built into the way we introduce new technology, not discarded as an impediment to it.

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