How accessible are Microsoft Word documents?

Microsoft Word is the world's most popular word processing software application, and files created with Word (typically ending in .DOC) are increasingly common as a means of distributing materials over the web, including materials used in education.

The greatest problem in distributing Word documents is that doing so assumes that all recipients have Microsoft Word. In cases where the entire audience is known, this may be an accurate assumption. For example, in an organization where Word is installed on all classroom computers, all employees do have access to Word. However, for documents with larger distribution or where users' technology is unknown, some recipients may not have Word and may be unable or unwilling to procure it, since it is not free. In contrast, most web browsers can be downloaded for free, and all of them can display HyperText Markup Language (HTML) documents; therefore, unlike a Word file, an HTML document can potentially be opened by anyone who requests it.

One solution is for organizations or individuals to download free, open-source word-processing software such as OpenOffice. OpenOffice is a multi platform and multilingual office suite and an open-source project. Compatible with all other major office suites, the product is free to download and use. By using an open-source application such as OpenOffice, users can access Microsoft Word documents, as well as other MS Office documents.

Beyond availability, whether Word is a good choice for accessibility depends largely on the content structure of the document. Microsoft Word itself is a reasonably accessible application, and many individuals with disabilities use it comfortably on a regular basis to compose their own documents. However, as documents become more complex, they are increasingly likely to present challenges to users of assistive technologies, particularly blind individuals using text-to-speech software (screen readers).

To provide Word documents in an accessible electronic format, there must be "structural integrity" to a document. An accessible format is one that explicitly communicates a document's structure, including but not limited to headings, subheadings, and table structure. Document structure also allows for features such as alternate text for images, as well as form labels that can be explicitly associated with the fields they represent.

HTML provides the ability to add alternate text to images, which is read aloud by screen readers as a way of representing the content of each image. Word provides similar functionality. With most recent versions of Word, there is a field for alternate text in the Image Properties dialog > Web tab. If the author has added the appropriate alt text to a documents images and then chooses to convert a Word document to HTML or Adobe® PDF, the alternate text is passed on to the converted document.

HTML also provides extensive markup that allows users to explicitly define the relationships between table cells and the column and/or row headers that represent them. This is particularly critical for complex tables that contain nested columns or rows. Unfortunately MS Word provides no similar capability.

Another consideration is that screen readers and other assistive technologies tend to perform poorly when reading a Word document that is opened within a web browser. Much of the specialized functionality that allows users to read, navigate, and better understand a document within the Microsoft Word application is lost when the document is opened within a plug-in. Therefore, in order to experience maximum accessibility, users must download and save the document and then open it in Word. Though not in itself an accessibility problem, this process is burdensome for users.

Given all of these variables, whether Word is an accessible format is not a simple question to answer. It depends largely on the document content and complexity.

Two states have clearly documented their opinions regarding the accessibility of specific file formats within their laws and regulations. In Kentucky, SB 243 (only available as a Microsoft Word document), specifically in its accompanying regulations (704 KAR 3:455), defines three levels of file format accessibility. The highest (Level 1, or "full compliance") includes XML, XHTML, or HTML format; Microsoft Word falls under Level 2 ("provisional compliance"). Level 3 ("marginal compliance") includes "unlocked PDF."

By comparison, Chapter 219 of New York's Education Laws of 2003 ranks Microsoft Word along with ASCII (plain text) as its fourth and final option, behind full-text DAISY 3 (the preferred file format), HTML (second option), and structured PDF (third option).

A good article about Microsoft Word Accessibility is provided by WebAIM.