Use of PDFs and office documents

The NHS, like all public sector bodies, is required by law to make all of its content accessible.

This means following the principles of accessibility which are that all content MUST be:

• perceivable - users must be able to perceive the content on the page, by seeing it, hearing it, or another method
• operable - users must be able to use the content on the page, like forms, even if they don't have a mouse or screen
• understandable - users must be able to understand the content and tools
• robust - the content is compatible with the widest possible range of technologies and future technologies.

This is required under two main pieces of legislation:

• The Public Sector Bodies (Websites and Mobile Applications) (No. 2) Accessibility Regulations 2018

• The Equality Act 2010

These rules apply equally to content which is public, content which is restricted to certain users, and content which is internal only.

PDFs, which stands for Portable Document Format, are files which encode an entire document into a digital format.

It is based around the principle of maintaining documents electronically much as they would be in their physical form.

The vast majority of PDFs are not accessible. This means that people with accessibility needs, like those who use a screen reader, or with a visual impairment, might not be able to use the document.

Common reasons that PDFs fail accessibility standards:

• a lack of structured data such as a hierarchy of headings, which means people who cannot see the pages cannot orient or navigate properly
• they cannot meet the range of users' accessibility needs, for example, users cannot change colours or font size - this is easy in web content, but much more difficult or impossible in PDF documents
• many browsers, tools and extensions do not work with them - they often have problems with zoom, scroll, audio, image and keyboard navigation
• a lack of 'alt text' for images - alt text provides an alternative way to convey the information provided by the image to users who cannot necessarily see the image 
• they take users away from the website, opening in a new tab, window or software - and not all users have the right software

Some of these issues can be addressed, but others are much more difficult. This means that almost all PDFs are not accessible, and do not meet the legal standard required of public sector bodies.

This means that publishing information in a PDF format is likely to be unlawful, unless you also publish an accessible version.

Other problems with PDFs

Other reasons we avoid PDFs is because:

• they give people a poor user experience, especially on mobile
• they are hard to maintain and update, so users may get out of date and unreliable content
• if users find PDFs in search results, they get them without any supporting context or material
• search engines do not rank PDFs high in search results
• it's difficult to collect data on how people use PDFs, and that makes it difficult to identify problems and improve them

Web content is easier for most users than long documents.

This is because:

• it is easy to jump between web pages using links, and to navigate backwards again
• content can be made to fit the context
• search is more advanced on the web
• web pages can contain interactive content
• the web version is easier to keep up to date

Whilst PDFs can do some of these things such as internal anchor links, they cannot do others such as forward and back navigation.

This means that for most users, web content is much more useful.

It is possible to create PDFs which meet the accessibility standards, and these are called PDF/UA files, where UA stands for Universal Accessibility. The standard for these is defined by the International Standards Organisation in ISO 14289-1:2014.

These PDF files are heavily structured, and contain three distinct views:

• a physical view, which most readers would see on screen
• a tags view, which screen readers and assistive technology would see; and
• a content view, based on the order of objects, and which allows users to perform tasks such as reflowing, where they change things like pagination

It is technically challenging, and very time consuming to create PDF/UA documents, and it is beyond the everyday skill set of most content creators.

In general, most users find web content to be easier to use and navigate, than a separate structured document, and the web content is significantly easier to create within the content management system of a well-built website than it would be to create as a PDF/UA.

For this reason, teams should always consider web content as the primary method of communicating information.

There are a few limited exceptions, and in these cases a PDF might be appropriate.

These include:

• documents designed for printing out, like a poster
• documents which must be produced as a document for legal reasons, such as an annual report which must be laid at parliament

In these cases, you must still consider accessibility, and this usually means:

• ensuring that the PDF meets the PDF/UA standard
• also making the information within the document available in a web format

There are many PDFs which have already been created. In some cases, this is acceptable, but in others the team have a duty to convert them to an accessible format, usually web pages.

The regulations are specific and give an exemption for "office file formats published before 23 September 2018, unless such content is needed for active administrative processes relating to the tasks performed by the public sector body."

This means that if the document was created before 23 September 2018 it can stay as a PDF or office document, but only if it is not in current use.

If your document:

• is the current version for an active process; or
• was created after 23 September 2018; or
• receives a major update

then it must, by law, be made accessible, and converted to web content.

Web content can be made to do all the same things as a document, including chapters, headings, and diagrams.

It can also be made to do far more, from interactive graphs, to expanding sections.

NHS Digital teams wanting to convert their content should contact [email protected] for more information. Teams in other organisations should contact their web team.