## AMA Manual of Style - Stacy L. Christiansen, Cheryl Iverson 2020

# Spacing With Mathematical Symbols

Mathematical Composition

Thin spaces (a space character that is usually 1 ⁄ 5 or 1 ⁄ 6 the width of an em dash; the Unicode value for the 1/6 em space is 2009) should be used before and after the following mathematical symbols when they are used as verbs, conjunctions, or operators: ±, =, <, >, ≤, ≥, +, −, ÷, ×, ⋅, ≈, ∼, ∩, ∫, Π, Σ, and |. Examples follow.

When symbols are used as adjectives, they are set close to the number.

A temperature of —2 °C

The choice of <.05 as the value for statistical significance is essentially arbitrary.

All large polyps (≥20 mm) were resected.

The following are more examples of symbols set close to numbers, superscripts and subscripts, and parentheses, brackets, and braces.

**Principal Authors:** Lauren Fischer and Paul Frank

**Acknowledgment**

Thanks to Karen Boyd, formerly with JAMA Network, Rochelle Lodder, formerly with JAMA Network, and Paul Ruich, JAMA Network, for careful review of this chapter.Additional Information: Coauthor Paul Frank died in 2015.

**References**

1.Design Science. MathType. Accessed November 30, 2018. http://www.dessci.com/en/products/mathtype/

2.The LaTeX Project. LaTeX—a document preparation system. 2015. Accessed July 23, 2019. https://latex-project.org/

**Additional Readings**

Style Manual Committee, Council of Science Editors. *Scientific Style and Format: The CSE Manual for Authors, Editors, and Publishers.* 8th ed. University of Chicago Press/Council of Science Editors; 2014.

Swanson E, O’Sean A, Schleyer A. *Mathematics Into Type*. Updated ed. American Mathematical Society; 1999. Accessed July 23, 2019. https://www.ams.org/publications/authors/mit-2.pdf