Fewer doctors will be manning the out-of-hours call systems in one Kent region but the organisation says patients will not be put at risk.

On Call Care, which manages the out-of-hours system in Maidstone, Tonbridge, west Kent and Sussex for the NHS, says the changes are needed because it has lost revenue after the reorganisation of Primary Care Trusts in Sussex.

It will reduce doctors' rota hours by five per cent and plans to monitor how long doctors spend on the phone, their referral rates to A&E and how many patients are given telephone advice or home visits.

The chairman of the Maidstone Division of the BMA, Dr Paul Hobday, an On Call Care board member, said: "This is really just about tightening up efficiency. A lot of extra shifts were added last year, so it is not like masses of doctors are being lost."

In an email to all doctors, chief executive and medical director Dr Mark Reynolds said: "'Dr Anxious' can produce more than twice as much work for the system as 'Dr Perfect', and 'Dr Referalot' can send four times the average to 999 or to hospital."

Deputy chief executive Carolyn Thomas said: "We still want doctors to treat patients as they see fit. But we would also want to know if a doctor was taking an hour on just one phone call."