People from all backgrounds and of all ages across the UK love to carry out safe shopping online. But a study from Sigma has found that sites which offer customers the opportunity to book holidays and make other travel arrangements are letting the side down when it comes to accessibility.

In particular, the report set out to determine how well optimised sites are for visitors who suffer from common impairments, such as partial sightedness and hearing problems, with a maximum score of 35 awarded to online outlets which are able to accommodate this type of customer with ease.

The least accessible site for people with these disabilities was found to be Co-Operative Travel, which scored just 17 points and was criticised for problems including small fonts, a lack of responsiveness and tiny interface elements which made it tough to interact with effectively.

Some well known brands which fared a little better but still have plenty of room for improvements include Airbnb, British Airways and Virgin Airways. All three scored 23 on the usability scale for their sites, according to Econsultancy.

Businesses which offer safe shopping online not only have to think about providing adequate levels of security and comprehensive access to a wide array of products and services; they also need to optimise the design of the interface and the layout of pages, to avoid excluding certain groups of customers.

Catering to the specific needs of disabled visitors is something that all retailers should aspire to achieve. And this is especially true in the age of prevalent mobile internet use, since touchscreen displays are now the standard for most visitors, meaning interactivity and intuitiveness cannot be ignored.

A comprehensive video detailing some of the testing processes that analysts used to assess the merits and pitfalls of major travel sites has been published on YouTube, giving a better idea of what approaches work best from a usability perspective.