Should Autism Spectrum Disorder Be Capitalized? A Style and Usage Guide

Usually, no. In general prose, write autism spectrum disorder in lowercase. Capitalize the first word only when it begins a sentence, or follow the capitalization rules for a title or heading. The acronym ASD is capitalized.

A formal diagnosis does not automatically require title case in ordinary writing. If you are transcribing a document that uses a particular capitalization, keep its wording when accuracy requires it. Otherwise, lowercase is a clear default for the full term.

The general rule

Autism spectrum disorder is the name of a condition, not a proper noun. For that reason, lowercase is appropriate in a sentence such as: “The report discusses autism spectrum disorder.” The word autism is also lowercase in ordinary prose.

This approach matches the way the CDC writes the phrase in its public-facing material. It is also consistent with general style guidance to lowercase names of diseases and disorders unless a name contains a proper noun. For details about a specific publication, consult its style guide: the APA Style Blog, AP Stylebook, and AMA Manual of Style are useful references, but their complete rules may depend on the context and edition.

The phrase may appear in title case in a heading or title, depending on the publication’s rules. That is a choice about title formatting, not evidence that the condition’s name is normally capitalized. For example, a title using title case might read “Understanding Autism Spectrum Disorder,” while the same phrase in a sentence would ordinarily be “understanding autism spectrum disorder.”

A sentence beginning with the term also requires an initial capital because it is the first word: “Autism spectrum disorder is discussed in the report.” That capitalization follows the sentence position, not a special rule for the diagnosis.

Why the capitalization can vary

Writers may encounter uppercase versions in clinical forms, diagnostic records, educational documents, or headings. A document may capitalize a label to match its own formatting or to distinguish an entry from surrounding text. That does not mean every writer should capitalize the phrase in running prose.

The distinction is between reproducing a source and writing in your own voice. When quoting or accurately copying a form, preserve its capitalization. When describing the condition in a general article, report, or email, use lowercase unless the relevant style guide specifies otherwise.

The acronym follows a separate convention. Write ASD in uppercase, whether it appears in a sentence, heading, or table. The acronym does not change the capitalization of the full phrase: “autism spectrum disorder (ASD)” is a standard way to introduce it in prose.

One example

Suppose you are writing a report about a study. In the body text, write: “The study included participants with autism spectrum disorder (ASD).” If you later use the acronym, write “ASD” in uppercase. If the sentence starts with the full term, capitalize the first letter: “Autism spectrum disorder is the subject of the report.”

If the report has a heading, apply the publication’s heading style. It might use sentence case, such as “Autism spectrum disorder in the study,” or title case, such as “Autism Spectrum Disorder in the Study.” Follow the same heading rule throughout the document. In either format, the heading’s capitalization does not change the lowercase default for the phrase in ordinary sentences.

Keep identity language separate

Capitalization of autism spectrum disorder is a style question about the name of a condition. It is separate from how a person describes their identity. Some people use “autistic person”; others prefer “person with autism.” When writing about an individual, use the language that person prefers when you know it. For general writing, avoid assuming that one phrasing is right for everyone.

That preference does not create a general rule to capitalize autistic or autism. Follow the person’s own usage if they capitalize a term in their stated identity, and follow the style guide for other contexts.

Key Takeaways

• Use autism spectrum disorder in lowercase in general prose.
• Capitalize the first word when it begins a sentence, and apply your publication’s rules to titles and headings.
• Write the acronym as ASD.
• Preserve capitalization when accurately quoting or transcribing a source.
• Follow an individual’s stated preference for identity language; treat that as separate from the capitalization of the diagnostic term.