Collaboration Tools Accessibility User Requirements

W3C Group Draft Note

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This document outlines various accessibility-related user needs, requirements and scenarios for collaboration tools. The tools of interest are distinguished by their support for one or more specific collaborative features. These features include real-time editing of content by multiple authors, the use of comments or annotations, and revision control. A Web-based text editor or word processor offering all of these features would be a central example of such a collaboration tool.

The accessibility-related user needs and corresponding requirements described in this document may be implemented in the collaboration tool itself, or elsewhere, for example in an assistive technology such as a screen reader. The scope of the discussion is not limited to problems that can be solved in the design or implementation of the collaboration tool. Instead, a holistic approach is taken that gives foremost priority to the user's perspective, leading to the identification of solutions that may be implemented by different components of the software involved in performing a collaborative task.

Although the user needs and associated requirements identified in this document are not normative accessibility guidance, they may influence the evolution of future accessibility guidelines, technical specifications, or features of collaboration tools and assistive technologies. They are relevant to software developers who contribute to any of these aspects of the collaborative experience.

Status of This Document

This section describes the status of this document at the time of its publication. A list of current W3C publications and the latest revision of this technical report can be found in the W3C technical reports index at

This document was published by the Accessible Platform Architectures Working Group as a Group Draft Note using the Note track.

Group Draft Notes are not endorsed by W3C nor its Members.

This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.

To comment, please open a new issue in the CTAUR GitHub repository, if it's not feasible for you to use GitHub, send comments in plain text e-mail to:, include [CTAUR] as the beginning of your subject line of your email. Please include your comments in the body of the message, not as a binary attachment which we will be unable to process. Please send comments by 30 December 2022.

Editor's note

Editor's Note: Contributing to this Document

This publication is a First Public Working Draft Note (FPWD) of a document intended to become an Accessible Platform Architectures (APA) Note. The intent of this+(and all) APA First Public Working Draft Note publications is to gain a wider review of its content and solicit feedback on user needs that may have been missed, underrepresented, or sub-optimally described at this early draft stage.

One known area where feedback is needed and expected is how collaboration tools can support people with cognitive and learning disability. The W3C Cognitive and Learning Disability Task Force (COGA TF) is actively reviewing this draft, and is providing feedback for incorporation in a future draft of this document based on their work in this area. An early view of COGA input to this document is available.

APA encourages review and feedback in other areas to ensure future drafts are as comprehensive as possible.

The W3C Patent Policy does not carry any licensing requirements or commitments on this document.

This document is governed by the 2 November 2021 W3C Process Document.

1. Introduction

1.1 What are collaboration tools?

For the purposes of this document, a collaboration tool is any software that supports features designed to facilitate the interactive creation, editing or annotation of content by multiple contributors. Examples of collaboration tools include

1.2 Distinctive features of collaboration tools

This document addresses features unique to collaboration tools, rather than features which they share in common with other types of Web application or with application software in general. Indeed, any tool that has one or more of the features addressed here has the potential to benefit from consideration of the user needs and corresponding requirements elaborated in the sections that follow.

The distinctive capabilities of collaboration tools are illustrated by the examples in section 1.1 What are collaboration tools?. For purposes of accessibility to people with disabilities, it is important to consider how these features may be manifest in the user interface of the tool. From this perspective, the distinguishing features may be described as follows.

Real-time co-editing
A feature enabling multiple authors to edit the same content simultaneously. The changes introduced by different authors are combined in real time, using algorithms such as operational transformation [concurrency-control]. The combined changes are then made immediately visible in all of the participating authors' editing sessions. The effect is that each author can perceive, in real time, the changes made by collaborators, including the location of another author's focus within the content.
Annotation of content with comments
Some tools enable users to associate comments with parts of the content that is being read or edited. In systems such as word processors, replying to comments is supported, allowing threads of discussion to be associated with parts of a document.
Comparing revisions
Some systems can display the differences between revisions of a text for purposes of comparison.
Suggested changes
Some word processors can show changes (insertions, deletions and formatting-related modifications) made by collaborators, which an author can choose to accept or reject. These revisions are sometimes referred to as suggested changes or as tracked changes. Each change may be accompanied by metadata, for example the identity of the author who made the change, and a time stamp.

1.3 Collaboration tools and accessibility

By following established guidance such as that of Web Content Accessibility Guidelines (WCAG) [wcag21], designers of collaboration tools can ensure that their user interfaces are perceivable to and operable by a wide range of users with disabilities. However, implementing current guidelines is not sufficient by itself to ensure that such a user interface is understandable, or that it can be used efficiently to complete collaborative tasks.

The collaboration-related features of these tools can impose significant cognitive demands on the user. This is especially so if a screen reader is used, and the interactive elements of the application are presented serially in speech or braille. For example, a screen reader may present details of suggested changes and comments while the user is reading a document in a word processor. Details of collaborators' activities in the document may be presented in real time. The screen reader user may also be expected to communicate with collaborators (e.g., in a meeting) while undertaking editing tasks. Moreover, at any time, incoming changes made by collaborators may alter the text that the user is reading or editing.

Due to the cognitive demands created by collaboration tools in the practical and social contexts in which they are used, strategies for improving accessibility are desirable that extend beyond current W3C guidance.

Editor's note

Which aspects of the cognitive complexity are most challenging to a variety of users with learning or cognitive disabilities? Should we clarify further in the text that sensory disability as such (perception) is not the issue here; it is fundamentally a cognitive issue even for screen reader users (whether or not any cognitive disability is involved). Also, are there specific issues of importance to users of captions or sign language in dividing attention between communication and use of the collaboration tools?

2. User need definition

User needs relate to what conditions a particular application or platform must satisfy for a user with a disability to complete a task or to achieve a particular goal. User needs are dependent on the context in which an application is used, including the user's capabilities and the environmental conditions in which interaction with the interface takes place. For example, the cognitive demands imposed by interacting with the collaboration-related features of an application depend not only on the needs and capabilities of the user, including the possible presence of assistive technology, but also on the context. A collaborative task that the user can perform independently while working alone in a distraction-free environment may become cognitively burdensome if performed in a situation such as a meeting. Working with comments and suggested changes in a document may become more cognitively demanding if other authors are simultaneously editing the same content, and the user needs to be aware of their activities (e.g., to avoid introducing conflicting changes) while still performing the editing task. The use of different input types and methods, such as speech input or switch-based input, can affect the amount of time required to enter and edit text, as well as the user's ability to respond to potentially disruptive changes introduced by collaborators.'

3. Real-Time co-editing


Status messages need to be made available to assistive technologies, including screen readers. See Web Content Accessibility Guidelines (WCAG) 2.1 [wcag21], success criterion 4.1.3, and the associated definition of status message.

Editor's note

What strategies should be used to limit the cognitive demands imposed on people with needs arising from various learning or cognitive disabilities? To what extent do they overlap with the issues raised above and discussed in the research literature, which focuses on screen reader users?

4. Annotations


See Web Content Accessibility Guidelines (WCAG) 2.1 [wcag21], success criterion 1.3.1.


REQ 8 may be valuable to users in general, and it should be considered for inclusion as a feature of collaboration tools themselves.

Editor's note

Does User Need 7 also apply to some people with learning or cognitive disabilities? What additional strategies should be suggested, if any?

5. Version control features

5.1 Suggested changes


See Web Content Accessibility Guidelines (WCAG) 2.1 [wcag21], success criterion 1.4.1.

5.2 Presenting Differences Between Revisions

6. Notifications and Messages

Collaboration tools may send notifications to the user for a variety of reasons. For example, a user may be notified if a collaborator submits changes to a document or project, or adds a comment. These notifications may be delivered via operating system facilities, or by a messaging service, such as e-mail or an instant message protocol. Moreover, the collaboration tool may support commenting, issue tracking, or other forms of interaction via external messaging. These optional capabilities are addressed in the following user needs and system requirements.

A. References

A.1 Informative references

Concurrency control in groupware systems. Clarence A. Ellis; Simon J. Gibbs. Proceedings of the 1989 ACM SIGMOD international conference on Management of data. 1989.
Web Content Accessibility Guidelines (WCAG) 2.1. Andrew Kirkpatrick; Joshue O'Connor; Alastair Campbell; Michael Cooper. W3C. 5 June 2018. W3C Recommendation. URL: