In a survey by healthcare information provider OnMedica, 60 per cent of doctors said the 'value of NHS Direct needs to be re-evaluated'.
Nearly half of the 500 GP and hospital doctor respondents said NHS Direct increases workload by referring too many patients.
Only 10 per cent said that it provided an excellent advice service while 13 per cent of GPs said they no longer recommended it to patients.
An NHS Direct spokeswoman said performance figures for. the organisation last month showed that of 467,000 calls answered, 48 per cent were completed without onward referral.