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Grammar and style

AAD adheres to AP style. Below is a collection of common grammar and style issues.

Abbreviations and acronyms: If there’s a chance your reader won’t recognize an abbreviation or acronym, spell it out the first time you mention it. Then use the short version for all other references. If the abbreviation isn’t clearly related to the full version, specify in parentheses. Generally, the style of an acronym should be National Aeronautics and Space Administration (NASA). In cases where the acronym refers to an uncapitalized phrase, such as absent without leave (AWOL), do not capitalize the initial letters just because they are identified as part of an acronym. Do not use apostrophes in a pluralized acronym, such as nurse practitioners (NPs).

Aka: The proper style for aka is all lowercase, without periods. Incorrect: a.k.a. Technically, this is an acronym for "also known as," but it has come into such common usage that a style exception is advised.

Alright: Never use alright. Spell out all right.

Ampersands: Don't use ampersands in sentences unless part of a brand name. It's okay to use ampersands in navigation and buttons.

Apostrophes: The apostrophe’s most common use is making a word possessive. If the word already ends in an s and it’s singular, you also add an ‘s. If the word ends in an s and is plural, just add an apostrophe. Do not use apostrophes in a pluralized acronym, such as nurse practitioners (NPs).

  • The donut thief ate Sam’s donut.

  • The donut thief ate Chris’s donut.

  • The donut thief ate the managers’ donuts.

Because vs. since: Generally, use “because” to refer to causally or logically connected subjects, not since. Correct: Because the changes are extensive. Incorrect: Since the changes are extensive. Generally, "since" should refer to time relations, not causal relations, though in some cases “since” may be used to avoid repetition.

Bolding and Italics: When words are styled with bold or italics, the styling should include any punctuation that follows the word. Correct: The dog is happy. Incorrect: The dog is unhappy. This is a common problem with colons and headers. This is Correct: This is not Correct:

Capitalization: We use a few different forms of capitalization. Title case capitalizes the first letter of every word except articles, prepositions, and conjunctions. Sentence case capitalizes the first letter of the first word. (Specific examples are in the Web elements and SEO section.)

  • Title case: AAD programs (e.g. Shade Structure Program), brand names, and periodicals.

  • Sentence case: Page titles, subheads and just about everything else.

  • When writing out an email address or website URL, use all lowercase.



  • Don't capitalize random words in the middle of sentences. Here are some words that we never capitalize in a sentence. 

    • website

    • internet

    • online

    • email

CMS: Although CMS has a plural name, it refers to a single institution within HHS. Thus, do not treat CMS as if it is plural. Correct: CMS's Incorrect: CMS' Correct: CMS has determined Incorrect: CMS have determined ...

Colons: Use a colon (rather than an ellipsis, em dash, or comma) to offset a list.

  • Erin ordered three kinds of donuts: glazed, chocolate, and pumpkin.

You can also use a colon to join two related phrases. If a complete sentence follows the colon, capitalize the first word.

  • I was faced with a dilemma: I wanted a donut, but I’d just eaten a bagel.

Commas: Serial commas (also known as the Oxford comma) When writing a list, use the serial comma.

  • Yes:

     David's favorite foods are donuts, pizza, and cake.

  • No:

     David's favorite foods are donuts, pizza and cake.

Never set off contractions that begin a sentence with a comma. Correct: But all things being equal. Incorrect: But, all things being equal. Otherwise, use common sense. If you’re unsure, read the sentence out loud. Where you find yourself taking a breath, use a comma.

Contractions: They’re great! They give your writing an informal, friendly tone. In most cases, use them as you see fit. Avoid them if you're writing content that will be translated for an international audience.

Dates: Generally, spell out the day of the week and the month. Abbreviate the month if followed by a year

  • Saturday, January 24

  • Saturday, Jan. 24, 2018

Decimals and fractions: Spell out fractions.

  • Yes: two-thirds

  • No: 2/3

Use decimal points when a number can’t be easily written out as a fraction, like 1.375 or 47.2.

Dashes and hyphens: Use a hyphen (-) without spaces on either side to link words into single phrase, or to indicate a span or range.

  • first-time user

  • Monday-Friday

Use an em dash (—) without spaces on either side to offset an aside.

Note than an em-dash is distinct from a hyphen. It is a dash the length of three character spaces. Use a true em dash, not hyphens (- or --).

  • The Academy's DataDerm—just one of our Practice Management Center features—can help you improve quality of care.

  • Austin thought Brad was the donut thief, but he was wrong—it was Jennifer.

Use em-dashes sparingly. They can be useful for making parenthetical asides and for setting off complicated information. They become distracting when used excessively. Never use em-dashes in place of a comma. Wrong: As it happens—there actually is an answer.

Ellipses: Ellipses (...) can be used to indicate that you’re trailing off before the end of a thought. Use them sparingly. Don’t use them for emphasis or drama, and don’t use them in titles or headers.

  • “Where did all those donuts go?” Christy asked. Jennifer said, “I don't know...”

Ellipses, in brackets, can also be used to show that you're omitting words in a quote.

  • “When in the course of human events it becomes necessary for one people to dissolve the political bands which have connected them with another and to assume among the powers of the earth, [...] a decent respect to the opinions of mankind requires that they should declare the causes which impel them to the separation.”

When ellipses appear in a sentence, outside of brackets, they should not be set off by a space on either side, such as this...rather than this ...

Exclamation points: Use exclamation points sparingly, and never use more than one at a time. They’re like high-fives: A well-timed one is great, but too many can be annoying.

Like other punctuation, exclamation points usually go inside quotation marks. Like periods and question marks, they go outside parentheses when the parenthetical is part of a larger sentence, and inside parentheses when the parenthetical stands alone.

When in doubt, avoid!

Fewer vs. less: Fewer should be used instead of less when referring to distinct quantities. For example, there were once fewer entries in this style guide.

File extensions: When referring generally to a file extension type, use all uppercase without a period. Add a lowercase s to make plural.

  • GIF

  • PDF

  • HTML

  • JPGs

When referring to a specific file, the filename should be lowercase:

  • happypanda.gif

  • ilovedonuts.html

Healthcare vs. health care: Health care should be two words.

Like vs. such as: When citing an example of something, use the phrase "such as" rather than "like." Strictly speaking, such as provides an example, whereas like provides a similarity. Correct: You may use a coin, such as a quarter. Incorrect: You may use a coin, like a quarter.

Money: When writing about U.S. currency, use the dollar sign before the amount. Include a decimal and number of cents if more than 0.

  • $20

  • $19.99

Numbers: Spell out a number when it begins a sentence. Also spell out numbers that are below 10, unless they refer to the age of a person or animal. In any sentence that already contains a numeral, use the numeral in place of the word. In all other cases, use the numeral. This includes ordinals, too.

  • Ten new employees started on Monday, and 12 start next week.

  • There are 8, 9, or even 10 good possibilities.

  • I ate three donuts at the monthly birthday party.

  • Meg won 17th place in last year’s Halloween contest.

Numbers over 3 digits get commas:

  • 999

  • 1,000

  • 150,000

Write out big numbers in full. Abbreviate them if there are space restraints, as in a chart: 1k, 150k.

Percentages: Use the % symbol instead of spelling out "percent."

Periods: Periods go inside quotation marks. They go outside parentheses when the parenthetical is part of a larger sentence, and inside parentheses when the parenthetical stands alone.

  • Jennifer said, “I ate a donut.”

  • I ate a donut (and I ate a bagel, too).

  • I ate a donut and a bagel. (The donut was Sam’s.)

Physician titles

  • In first reference: Jamie Smith, MD (If they are an Academy fellow: Jamie Smith, MD, FAAD

  • In second reference: Dr. Smith

Capitalize individual job titles when preceding a name, but lower case when listed after a name •    Professor Jamie Smith, MD, FAAD •    Jaime Smith, MD, FAAD, professor of dermatology.

Pronouns: If your subject’s gender is unknown or irrelevant, use “they,” “them,” and “their” as a singular pronoun. Use “he/him/his” and “she/her/her” pronouns as appropriate. Don’t use “one” as a pronoun.

Question marks: Question marks go inside quotation marks if they’re part of the quote. Like periods, they go outside parentheses when the parenthetical is part of a larger sentence, and inside parentheses when the parenthetical stands alone.

Quotation marks: Use quotes to refer to words and letters, titles of short works (such as articles), and direct quotations.

Periods and commas go within quotation marks. Question marks within quotes follow logic—if the question mark is part of the quotation, it goes within. If you’re asking a question that ends with a quote, it goes outside the quote.

Use single quotation marks for quotes within quotes.

  • Who was it that said, “A fool and his donut are easily parted”?

  • Jennifer said, “A wise man once told me, ‘A fool and his donut are easily parted.’”

Quotes: When quoting someone, use present tense. •    “Using the Practice Management Center has helped me master coding,” says Jamie Smith, MD, FAAD.

Ranges and spans: Use a hyphen (-) to indicate a range or span of numbers.

  • It takes 20-30 days.

Semicolons: Go easy on semicolons. They usually support long, complicated sentences that could easily be simplified. Try an em dash (—) instead, or simply start a new sentence.

States, cities, and countries: Per AP Style, all cities should be accompanied by their state, with the exception of: Atlanta, Baltimore, Boston, Chicago, Cincinnati, Cleveland, Dallas, Denver, Detroit, Honolulu, Houston, Indianapolis, Las Vegas, Los Angeles, Miami, Milwaukee, Minneapolis, New Orleans, New York, Oklahoma City, Philadelphia, Phoenix, Pittsburgh, St. Louis, Salt Lake City, San Antonio, San Diego, San Francisco, Seattle, Washington.

Use postal abbreviations for states when they follow a city name.

On first mention, write out United States. On subsequent mentions, US is fine. The same rule applies to any other country or federation with a common abbreviation (European Union, EU; United Kingdom, UK).

Telephone numbers: Use dashes without spaces between numbers. Use a country code if your reader is in another country.

  • 555-867-5309

  • +1-404-123-4567

Temperature: Use the degree symbol and the capital F abbreviation for Fahrenheit.

  • 98°F

Time: Use numerals and am or pm, with a space in between. Don’t use minutes for on-the-hour time. 

  • 7 a.m.


  • 7:30 p.m.

Use a hyphen between times to indicate a time period. 

  • 7 a.m.-10:30 p.m.

Specify time zones when writing about an event or something else people would need to schedule. 

Abbreviate time zones within the continental United States as follows:

  • Eastern time: ET

  • Central time: CT

  • Mountain time: MT

  • Pacific time: PT

When referring to international time zones, spell them out: Nepal Standard Time, Australian Eastern Time.

Towards vs. toward: Use toward, not towards.

URLs and websites

  • Capitalize the names of websites and web publications. Don’t italicize.

  • Avoid spelling out URLs, but when you need to, leave off the http://www.

  • Do not add bold styling to a hyperlink.

  • Be careful not to include spaces in the link text. This just doesn't look right.

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