Experts said that if the changes go ahead, it would mean slightly longer waiting times than under today’s targets.
Under the current measures, 92 per cent of patients are supposed to receive treatment within 18 weeks.
But this target has been repeatedly missed, with latest monthly figures showing 84.5 per cent of patients seen within this time.
Health officials have already proposed axing the 18 week target, and replacing it with a measure based on “average” waiting times.
Now board papers produced by Northampton General Hospital Trust, one of the 12 NHS trusts testing new measures, show managers expect the average wait under such a system to be 8.5 weeks.
A waiting times expert told Health Service Journal that this would mean a lowering of standards, as the existing target means an average wait of eight weeks.
NHS England said testing was still “ongoing” and no decisions “whatsoever have been made on any particular measure, including a mean wait”.
In March, NHS England announced proposals to scrap key targets for patients, including the four-hour A&E wait and the one to receive an operation within 18 weeks.