The annual numbers of doctors and nurses leaving active service in the National Health Service in England are published quarterly by NHS England as part of their NHS Workforce Statistics Collection. The data is available in the Turnover SG and Region HC tab at the following link:
The data includes staff employed by NHS trusts and commissioning bodies, but excludes staff directly employed by primary care, general practitioner surgeries, local authorities and other providers such as community interest companies and private providers. Leavers includes staff leaving to work in primary care, for local authorities and for private providers, including those doing NHS commissioned work. Doctors in training will rotate in a planned way around the wider health care system as part of their training and so have higher recorded leaver rates. The statistics also count those taking breaks in paid employment, such as unpaid maternity leave.