Web Accessibility Barrier

Any element, design pattern, or technical implementation on a web page that prevents or hinders people with disabilities from accessing, understanding, or interacting with content. Common web accessibility barriers include images without alternative text, videos without captions, forms without labels, insufficient colour contrast, content that requires a mouse, and complex layouts that confuse screen readers. The Web Accessibility Barrier (WAB) score is a quantitative metric developed at the University of Pittsburgh that measures the density of accessibility barriers on a website by normalizing actual WCAG violations against potential violations, weighted by priority level.