Price comparision websites have soared in popularity in recent years
Price comparison websites should have their data checked by an independent authority to make sure it is accurate, according to a university think tank.
The number of comparison websites has mushroomed over the last few years - as more of us use them to find a cheaper deal on a range of financial products.
Most of the sites receive a commission from the companies they recommend.
The call for independent checks comes from the Centre for Competition Policy (CCP) at the University of East Anglia.
"I think there needs to be an independent authority which can check the information is impartial or perhaps run a comparison website itself," said the CCP's Catherine Waddams.
Why price comparison sites may not offer the best deals
Some of the comparison sites have signed up to a voluntary accreditation code, which is policed by the energy watchdog Energywatch.
Comparison sites that sign up to the code must include tariffs of all energy suppliers, not just those that might pay it a commission.
But the code only covers gas and electricity.
Information about products like insurance, credit cards and savings are not regulated.
The other criticism of the comparison sites is that different comparison websites may highlight different deals as being the best one for a particular consumer.
In addition, the sites are criticised for not normally revealing exactly how much commission or payment they earn from the companies.
The comparison sites say that the amount they get paid by various companies when consumers switch is "commercially sensitive".
But they deny any accusations of bias and say that they have made the process of finding a good deal much easier and have saved consumers millions of pounds.
This report will be broadcast on Saturday morning on BBC1 Breakfast at 06:00GMT and on News 24's Your Money at 10.35GMT