High street retailers are failing in their quest to boost web site accessibility despite overall improvements, according to the latest research from web consultancy Webcredible released this week.

The Accessibility for Ecommerce High Street Retailers 2007 report tested the sites of 20 of the UK's top high street retailers according to best practice guidelines, and found an average score of just over 50 percent.

Top was H Samuel with 76 percent, while HMV, B&Q, John Lewis and Argos completed the top five. Currys came last with a score of just 34.

Although there has generally been improvement in retailers' efforts to make their sites more accessible, many still fell down at the payment stage, according to Webcredible director, Trenton Moss.

Areas where sites could improve included adding in "skip links" to help users navigate content more easily, and highlighting links which can aid non-mouse users, the firm said.

"It is also important to remember that there are disabilities which hinder online shopping other than partial sight and blindness," explained Moss. "For example users with motor skill difficulties will find it hard to use a mouse and will need to navigate web sites using just the keyboard. It is essential that when 'tabbing' through a site headings stand out sufficiently and can be clearly read."