https://journals.sagepub.com/doi/abs/10.1177/001872081664096...

A high level of Web accessibility led to better performance (i.e., task completion time and task completion rate) than low or very low accessibility. Likewise, high Web accessibility improved user ratings (i.e., perceived usability, aesthetics, workload, and trustworthiness) compared to low or very low Web accessibility. There was no difference between the very low and low Web accessibility conditions for any of the outcome measures.