A GP survey found 62% of responding GPs agreed that third-party referral management schemes are eroding GPs' professionalism.
One-third (34%) said use of these schemes had increased in their area in the past year.
GPs attacked the practice as 'an appalling waste of time and money' that delayed patient access to care. One respondent said the schemes were 'insulting' for GPs.
This comes ahead of a vote on the matter at the LMCs annual conference in York next week.
Devon LMC will propose a motion calling for a government review of whether referral management centres are value for money.
It will call on GP leaders to recognise 'the lack of any evidence that the additional work, bureaucracy and costs that referral management centres impose on GPs is of any benefit to the efficient functioning of the NHS'.
A third (34%) of 606 GPs in the survey reported an increase in referral assessment in their area in the past 12 months, with just 3% witnessing a fall (see graphic). Some GPs supported referral management, saying the schemes 'raise standards and decrease soft referrals', and 'highlight learning needs of GPs to manage problems more themselves'. Another said there was a 'very efficient' set-up in their area.
Others said they had been put under pressure to refer through their local scheme. One GP partner in England said a local project that started as a 'very useful and helpful referral assessment service' was starting to become a 'referral blocking service'. The scheme amounted to 'arbitrary decisions made by unqualified administrators', said the GP. Others complained the schemes were 'designed to massage waiting list figures'.
One GP partner in England said: 'I thought I was the one trained in medicine to make choices regarding treatment. Apparently not.'
Another GP said: 'After 44 years, I think I know the best person to help my patients.'
A 2013 study in the British Journal of General Practice found referral management at one PCT was more expensive than internal peer review and did not reduce outpatient attendance rates.
GPC deputy chairman Dr Richard Vautrey said the schemes created 'an unnecessary barrier between GPs and consultants'. He said PCTs implementing such approaches had often later withdrawn them because they were not cost-effective.