Professional reviews online are the least likely to be trusted by consumers, with just 6% of people rating them trustworthy, according to Lightspeed Research.
Its survey UK internet users' online reviews experiences found 72% of people have read a review for a product online. Yet this figure drops for younger users; only 63% of 18-24-year-olds have read an online review.
Ralph Risk, marketing director at Lightspeed Research, said, "It was interesting that user review sites like Which? were the most trustworthy. A lot of people believe professional reviews aren't independent."
The research found 75% of review readers would change their mind about buying a product after reading up to three negative reviews.
The research polled 1,000 UK internet users in July 2008.