Although scientific and medical manuscript formatting requirements can vary considerably among journals, there are a number of general standards for documents.
The manuscript text should be written in black in a standard font, such as Times New Roman or Arial. On occasion, the journal will specify the font to be used, such as in Allergology International (“preferably Times New Roman”) and the Journal of Clinical Oncology (“a common font such as Helvetica, Arial or Times fonts”). It is crucial to avoid the use of non-standard or “exotic” fonts, such as SimSun and PMingLiu, because not all computers will have these fonts installed and any special characters may not be rendered correctly. In general, insert any special symbols (e.g., β, α, µ) in the same font as that used in the rest of the paper (use the Symbol tool in Microsoft Word). Some journals do, however, request that the Symbol font be used (e.g., Nucleic Acids Research); others state that either normal text or Symbol font is acceptable (e.g., Nature).
Generally, a 12-point font size should be used, as suggested, for example, by Nature and the Journal of Clinical Oncology. A smaller font size may be used to aid the presentation of data in tables as long as this does not hamper readability or contravene journal guidelines.
Double-spacing throughout the text is preferred by most journals. Double-spacing tends to be preferred as it improves readability for editors and reviewers and permits notes to be made on any paper copies of the manuscript. Of course, there are exceptions, such as 1.5 point for The Plant Cell, single-spacing for The Journal of Biological Chemistry, and, for Pediatrics, single-spacing for just the Title Page, Abstract, and References and double-spacing for the remainder. Note that The Journal of Biological Chemistry is an interesting case because the journal asks the author to format the manuscript as it would appear in the journal, with most of the paper in a double-column format. This appears to be necessary in order to speed the prepublication of an accepted paper (as a JBC Paper in Press). Most journals, however, prefer single-column pages. Again, a smaller spacing, such as 1.15 point may be useful when formatting tables, especially long ones, although it is sometimes discouraged.
Wide margins—for example, 1 inch/2.54 cm—should be used on all sides. Although most journals prefer a left-justified text (i.e., flush with the left margin and ragged on the right), such as the Journal of the American Pharmacists Association (“do not use the word processor's options to justify text”), some journals do request fully justified text (flush with both left and right margins), such as Diabetes (“the main text should [be] double spaced with justified margins”).
Some journals have other specific manuscript formatting requests, such as page numbers and line numbers. These will be detailed in the Instructions to Authors section of the website of the target journal. Page numbers are useful for reviewers and should be used unless other specified.
In the absence of journal guidelines, my advice is to use the following:
· Font type: Times New Roman
· Font size: 11 or 12
· Spacing: 1.5 or double
· Margin: 1 inch/2.54 cm on all sides
· Page numbers: Bottom center of page
Banner image: Anatomical drawings by Leonardo da Vinci.