Guide to Guideline 3.1 Level 3 Success Criterion 5

3.1 L3 SC5

Key terms and important concepts


A version of content which some users may choose instead of or in addition to another version of the content. Supplements may use different media. For example, there may be versions in text, graphics, and audio.

Intended audience

The people for whom the Web site, application, or other resource has been created. The audience may be large or small, local or global. The intended audience may be deeply knowledgeable about the topic, or completely uninformed.

Education level

Years of school completed, or highest degree achieved.

Upper secondary education level

Typically begins at ages 15 or 16 and lasts for approximately 3 years. The educational programmes included at this level typically require the completion of some 9 years of full-time education (since the beginning of level 1 [primary education]) for admission or a combination of education and vocational or technical experience and with as minimum entrance requirements the completion of level 2[lower secondary education, such as middle school or junior high school in the US] or demonstrable ability to handle programmes at this level. (Source: International Standard Classification of Education 1997. UNESCO. Retrieved 22 June 2005 from

Primary education level

Usually begins at age 5, 6, or 7 and continues for six years of full-time schooling. Source: International Standard Classification of Education 1997. UNESCO. Retrieved 22 June 2005 from

Readability formula

Readability formulas predict whether text will be easy or difficult to read. Readability formulas assume that longer sentences are more complex than shorter ones, and therefore harder to read. Readability formulas also assume that shorter words are easier to read than longer ones.

In some languages, readability formulas measure sentence-length by counting characters instead of words. Readability formulas for languages that use multiple scripts within a single document (such as Japanese katakana and hiragana) may also consider the number of different scripts used in the text as a measure of difficulty.

Results of readability tests are often expressed in terms of the education level needed to recognize words and sentences in the text. Thus readability formulas can help authors write content that matches the education level or reading ability of the intended audience.

Delivery unit

NOTE: [Note: add plain-language paraphrase approved at 2005-04-28 call.]

A set of material transferred between two cooperating web programs as the response to a single HTTP request. The transfer might, for example, be between an origin server and a user agent.

Intent of this success criterion

The intent of this success criterion is to ensure that supplementary aids are provided for complex text. It defines a threshold that establishes when simpler alternatives are required. It also defines the required reading level for one type of alternative, the text summary.

The threshold for deciding when text is complex enough to require supplemental versions is set at the upper secondary education level as defined by the International Standard Classification of Education (UNESCO, 1997). . In the United States and Japan, for example, as well as other countries, this corresponds to the 10th grade.

The readability requirement for text summaries is set no higher than primary education because many people with learning disabilities read at or below this level.

Here are some additional points to consider:

This success criterion leaves authors free to present complex ideas and information while also meeting the needs of people with reading disabilities.

Technology-Independent techniques for Guideline 3.1 L3 SC5

Measuring readability

Follow these steps to measure the difficulty of text content:

  • 1. Choose a readability formula that will work with your content. Some issues to consider are:

  • a. Does the content include incomplete sentences such as list items, section titles, and so on? If so, consider using a readability formula that does not require complete sentences.

  • b. Choose passages that represent the different types or styles of text on your site. It is not necessary to include every word of a long text in the readability analysis. Many Web sites contain different types of information written in different styles for different groups of users. Test a representative sample.

  • c. Choose passages that meet the length requirements for your readability formula. Some formulas are based on 100-word passages; others use 150 words. And some describe procedures that can be used for very short texts.

  • 2. Apply the formula, or run the readability test in your word processor. (Note that commercial word processors may not give you a choice of which formula to use.)

  • 3. Interpret the results. This may involve plotting the score on a graph or, more often, looking up the score in a table or chart developed for the chosen formula.

  • 4. Record the results. Include the raw data as well as the readability score or grade.

Making text easier to read

Note: The following are techniques, not rules. Like any other technique, they must be used with skill and understanding in order to achieve good results.

  • Try to keep sentences short. For example, United States and European Union readability guidelines recommend 20 words per sentence as a good average.

  • Consider breaking longer sentences into two sentences, especially if the original sentence contains 25 words or more. (Note that this technique may require additional changes to both of the "new" sentences.)

  • Try to limit the number of long words, especially if you are not certain that the intended audience will know what they mean. (Note: different countries and different languages have different concepts of what "long" words are. English words with three or more syllables are usually considered "long." However, the Lix readability formula used in several European countries counts any word with six or more letters as a "long" word.)

  • Consider replacing long words with shorter ones that have the same or very similar meaning. some organizations publish lists of common words that may help you find good alternatives. Note: sometimes a long word that has the exact meaning you need is better than a shorter word that means something different.

Providing a summary

A summary gives a short statement of the most important ideas and information in a longer document. It uses different words than the original. The points in the summary may or may not follow the order of the longer document. The summary is often between 10 and 25 percent of the document’s original length, and in rare cases may be as much as 40 per cent of the document’s original length. Or it may be extremely short.

"Smartening up, not dumbing down"

Some people may regard this success criterion as forcing them to "dumb down" their work. That is, they may be concerned (sometimes rightly) that simplifying the text will lead to the loss of information or the blurring of important distinctions.

A good summary is always written after the original. This makes it easy to understand why authors often feel that important ideas and information are lost in the process.

But the reader’s experience may be very different. For the reader, the summary provides a stepping stone "up" to the longer and more complex document. For many readers, the summary offers a welcome preview of what is to come. For people with learning disabilities, that preview may be even more important.

For example, the summary may help someone with a reading disability decide that the full document is so important that it is worth the considerable time and effort that will be required to read it. The same summary might help another person with a learning disability understand that the article is not relevant to his or her interests. (This is an important function of the abstracts published in scientific and technical journals, for example.)

Using graphics to illustrate complex ideas, events, and processes

Users with disabilities that lead them to concentrate on decoding words and sentences are likely to have trouble understanding complex text. Charts, diagrams, animations, photographs, graphic organizers, or other visual materials often help these users. For example:

  • Charts and graphs help users understand complex data.

  • Diagrams, flowcharts, videos, and animations help users understand processes.

  • Concept maps and other graphic organizers help users understand how ideas are related to each other.

  • Photographs, videos, and drawings can help users understand natural or historical events or objects.

Providing a spoken version of text content

Some users who have difficulty recognizing (decoding) words in written text find it very helpful to hear the text read aloud. It is easy to provide this service using synthetic as well as recorded human speech. For example, there are a number of products that convert text to synthetic speech, then save the spoken version as an audio file. Cost depends in part on the quality of the voice used and whether the text is likely to change frequently.

Spoken versions of short texts and static text content: this method is effective for small amounts of text and for longer documents that do not change often.

  • Use a tool that converts individual documents or selected passages into synthetic speech. Choose the clearest, most attractive voice if a choice is available.

  • Save the spoken version as an audio file.

  • Provide a link to the audio version.

  • Identify the audio format (for example, .MP3, .WAV, .AU, etc.).

  • provide a link to a media player that supports the format.

Dynamic content: A server-side solution may be helpful when documents change frequently or when text is dynamically generated. Several companies provide server-based tools that allow users to select any text they are interested in and listen to it. Typically, the user selects an icon or button. This launches the text-to-speech conversion.

Technology-Specific Techniques for Guideline 3.1 L3 SC5

[List techniques for linking to spoken versions and/or grouping text and accompanying illustration in a DIV, etc.]

Advisory techniques: going beyond Guideline 3.1 L3 SC5

Benefits: How Guideline 3.1 L3 SC5 helps people with disabilities

This success criterion benefits people with reading disabilities who can understand complex ideas and processes presented in highly readable text or by other means, such as graphics illustrating relationships and processes or through the spoken word.

Reading disabilities such as dyslexia affect the ability to recognize individual words. Decoding must be automatic in order for people to read fluently. The act of decoding text word by word consumes much of the mental energy that most people are able to use for understanding what they read.

People with reading disabilities have become successful scientists, engineers, artists, actors, attorneys, surgeons, and skilled professionals in many other fields. But they are often at a significant disadvantage when ideas and information they need are available only in complex textual presentations. This success criterion does not limit the complexity of textual presentation. Instead, it asks authors and other content providers to present ideas and information more than one way in addition to the textual presentation.

Examples of Guideline 3.1 L3 SC5

Example 1: A scientific journal including readable summaries of complex research articles

A scientific journal includes articles written in highly technical language aimed at specialists in the field. The journal’s Table of Contents page includes a plain-language summary of each article. The summaries are intended for a general audience with eight years of school. The metadata for the journal uses the Dublin Core specification to identify the education level of the articles’ intended audience as "advanced" and the education level of the intended audience for the summaries as "eight years of school."

Example 2: Medical information for members of the public

A medical school operates a Web site that explains recent medical and scientific discoveries. The articles on the site are written for people who are not doctors. Each article uses the Dublin Core metadata specification to identify the education level of the intended audience as having completed 8 years of school and includes the Flesch Reading Ease score for the article. A link on each page displays the education level and other metadata. No supplementary versions are required because adults who have not begun upper secondary education can read the articles.

Example 3: An e-learning application.

An online course about Spanish cultural history includes a unit on Moorish architecture. The unit includes text written for students with different reading abilities. Photographs and drawings of buildings illustrate architectural concepts and styles. Graphic organizers are used to illustrate complex relationships, and an audio version using synthetic speech is available. The metadata for each version describes the academic level of the content and includes a readability score based on formulas developed for Spanish-language text. The learning application uses this metadata and metadata about the students to provide versions of instructional content that match the needs of individual students.

Example 3: A moderately difficult description of a complex and unfamiliar natural event.

In a dazzling and dramatic portrait painted by the Sun, the long thin shadows of Saturn's rings sweep across the planet's northern latitudes. Within the shadows, bright bands represent areas where the ring material is less dense, while dark strips and wave patterns reveal areas of denser material.

The shadow darkens sharply near upper right, corresponding to the boundary of the thin C ring with the denser B ring. A wide-field, natural color view of these shadows can be seen here.

The globe of Saturn's moon Mimas (398 kilometers, or 247 miles across) has wandered into view near the bottom of the frame. A few of the large craters on this small moon are visible.

Note: The description in Example 1 is taken from NASA – Sun-Striped Saturn, at Retrieved 2005-03-08.

Note: This description received a Flesch Reading Ease score of 57.9 and a Flesch-Kinkaid Grade Level of 9.9. This result means that people in the United States who have finished almost 10 years of school should be able to recognize the words and sentences.

Example 4: Description of a complex and unfamiliar natural event, rewritten to improve readability

The long thin shadows of Saturn's rings sweep across the planet’s northern regions. Bright bands within the shadows show areas where the ring material is less dense. Dark strips and wave patterns show denser areas.

The shadow darkens sharply near the top right. This is where the thin C ring meets the denser B ring. This shows a wide-field, natural color view of these shadows.

The globe of Saturn's moon Mimas (398 kilometers, or 247 miles across) appears near the bottom of the frame. A few of the large craters on this small moon are visible.

[Note: This edited version of the description was rated at 72.1 on the Flesch Reading Ease scale, meaning that people beginning their sixth year of school should be able to read the description. The changes include:

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