Consumers are likely to make costly mistakes when product descriptions force them to think about too many things at once, according to a new report by the Economic and Social Research Institute.

For the first time an Irish study has examined how the array of promotions can confuse the public.

A series of ten experiments conducted on 500 consumers tested if they could distinguish between good deals and bad ones.

It found that once people had to take into account more than two or three factors, they struggled to identify the best deals.

The central finding is that simple descriptions allow consumers accurately compare products.    

Internationally supervisory authorities are forcing companies to abandon complex advertising in certain markets.

The ESRI study was funded by the regulators who police consumer protection in financial, energy and telecoms markets, which means the study could play a big role in future regulation. 

Read RTÉ Business Editor David Murphy's blog: "How many variables before a customer feels bamboozled by choice?"