Recall of internet advertising is dramatically increased when combined with radio advertisements compared to online marketing used in isolation, a new study claims.

According to research by the Radio Ad Effectiveness Lab (RAEL), consumers are four-and-a-half times more likely to recall one internet and one radio advert than two online ads together.

Michael Orgera, member of the RAEL research committee, said: "Understanding how radio and the Internet together can significantly boost advertising attention levels is a tremendous advantage when creating a multi-platform campaign."

He added an increased number of media platforms and advertising messages had made it "increasingly more difficult" for companies to have an effect on consumers.

A study released by eMarketer earlier this month reported that about 66 per cent of American adult internet users claim they watch television while using the internet.

Although it was suggested using more than one media platform divides customers' attention span, author of the report, Debra Williamson, claims "it also opens up opportunities for advertisers".