WebAIM offers an API for their WAVE evaluation tool, albeit not as a free service.

Many others have said what I would have said, but I'll make a further comment on ARIA. For my regular work doing accessibility evaluations, more ARIA is a RED FLAG that the page will need to be fully tested by hand with multiple browser/screen reader combinations. The first rule of ARIA is don't use ARIA, but many sites and many frameworks abuse it horribly. 

Furthermore, keep in mind that ARIA is currently only utilized by screen reader technology. Disability access on the web is more than supporting screen readers for blind and low-vision users. Mobility issues, other sensory issues, supporting different cognitive abilities, and all forms of disabilities must be supported. 

That all said, automatic testing of websites will only get you so far. Keyboard navigation and focus control need to be tested by a human. Alternative text for images, link names, and other labels need to be evaluated for appropriateness. 

Katherine (Kate) Deibel | PhD
Inclusion & Accessibility Librarian
Syracuse University Libraries 
T 315.443.7178
[log in to unmask]
222 Waverly Ave., Syracuse, NY 13244
Syracuse University

-----Original Message-----
From: Code for Libraries <[log in to unmask]> On Behalf Of Caffrey-Hill, Julia
Sent: Friday, October 23, 2020 9:37 AM
To: [log in to unmask]
Subject: Re: [CODE4LIB] Web accessibility and ARIA

Hello Dr. Parthasarathi Mukhopadhyay,
I can provide some partial thoughts, and there are other members who have strong, knowledgeable perspectives that may want to chime in also.

Re: 2. 
- For ARIA, there's consensus that a high number of ARIA found on a page is not necessarily an indicator of accessibility and, to the contrary, a high score is a red flag that may indicate abuse of ARIA tags. They are easily mishandled. There are others in this community, namely Katherine Deibel, who are prolific on this topic that I hope can chime in or link to part presentations/resources.
- For your study, as it relates to ARIA specifically, I recommend AXE browser extension (https://www.deque.com/axe/). I don't think an API is available for it, but it is good for validation, and I believe is suited to a quantitative study. There is a learning curve on understanding it. Deque Systems, according to their training, split off from the team behind WAVE, and built out the tool's capacity for testing ARIA tags.

Re: 3
- In terms of a globally recognized quantitative indicator, I'm not aware of one. A combination of different tools is recommended, and they do have their weak spots. I prefer mixed methods to test for web accessibility. 
- For a large number of websites at a time, I understand the need for a framework. For auditing our e-resources for accessibility, Towson University adapted a framework from Princeton University, who in turn adapted it from another library. My colleagues and I recently presented on how to do this approach (Description: https://wp.towson.edu/tcal/one-step-at-a-time-assessing-e-resources-for-accessibility-compliance/ Recording: https://www.youtube.com/watch?v=zQZjTeW-69E&feature=youtu.be  - 40 mins) - I hope that's helpful and if so, I'd be interested to hear about it.

All the best,
Julia Caffrey-Hill
Web Services Librarian
Towson University

-----Original Message-----
From: Code for Libraries <[log in to unmask]> On Behalf Of Parthasarathi Mukhopadhyay
Sent: Thursday, October 22, 2020 7:55 AM
To: [log in to unmask]
Subject: [CODE4LIB] Web accessibility and ARIA

[EXTERNAL EMAIL - USE CAUTION]

Hello all

We are trying to measure web accessibility of some Indian institutes/universities/libraries in the form of a score and then rank those institutes/universities/libraries against the score (still at the idea plane). The plan is to fetch data through API in a data wrangling software for further analysis. My questions are as follows:

1) Are there other services (apart from WAVE) that provide results in JSON format through API?
2) What is the significance of *ARIA* in determining such a score for web accessibility? Does a higher number of ARIA indicate a better accessibility? Or is converse true?
3) Is there any globally agreed-upon indicator for web accessibility?

Best

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Dr. Parthasarathi Mukhopadhyay
Professor, Department of Library and Information Science, University of Kalyani, Kalyani - 741 235 (WB), India
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