Consultation times of only eight minutes or less are unfair to patients. It does not give the space they need for reassurance and discussion

Dr John Chisholm, BMA

However, there are fears in the UK that increasing pressures on doctors are cheating them of the opportunity to spend enough time with each patient.

Many of the 25 separate studies analysed by the scientists looked at the effects of reassuring patients about treatment - half of these showed a positive effect.

Four of these assessed a combination of this, and the effect of emotional care - a warm and sympathetic approach by the doctor.

Three of these showed a beneficial effect to the patient.

Dr Chris van Weel, from the University Medical Centre, in Nijmegen, Netherlands, said: "The care is low in technology, rich in personal touch.

"The continuity of care by one person and over times strengthens the trust between patient and practitioner and enables the doctor to accumulate knowledge of the patient's personal and family circumstances."

However, the British Medical Association (BMA), said that patients were being shortchanged because of doctors' excessive workload in both the GP's surgery and hospital care.

Dr John Chisholm, chairman of the BMA's GP's Committee, said: "Patients need more time with their doctors. Consultation times of only eight minutes or less are unfair to patients.

"It does not give the space they need for reassurance and discussion of the treatments they need or advice on how to live with chronic illness.

"For doctors all the pleasure of medicine is destroyed by the conveyor-belt pace."

Mr Derek Machin, deputy chairman of the BMA's consultants' committee said: "We try to fast-track patients through the system, squeezing extra appointments into outpatient clinics, discharging patients at lightning speed and putting quantity ahead of quality."