In text and headings, use sentence case (first letter upper-case and subsequent letters lower-case, except for proper nouns and abbreviations).
This table lists exceptions, where upper-case letters should be used:
| Section | Usage | Further information |
| Book titles and journal titles (but not book chapter titles or journal article titles) | Write in full using title case (all major words start with an upper-case letter) | References: reference fields |
| Some bibliographic databases | The preferred format for the following databases is all upper-case letters: MEDLINE, CENTRAL, OLDMEDLINE, and CINAHL (not CINHAL). Some databases use a mixture of lower-case and upper-case letters, for example, Embase (not EMBASE), PsycLIT (not PsychLIT) and PsycINFO (not PsychINFO). | Search methods |
| Abbreviations | Use upper-case letters to explain the abbreviation or acronym only if required by the abbreviated term, for example:
| Formatting of abbreviations |
| Pharmaceutical drug names | Pharmaceutical drug brand names, if used, should be written with a capital letter, but international standard drug names should not be capitalized. | Names and common terms: names |
| Organism names | Names of organisms are given in the form Genus species (e.g. Plasmodium falciparum, Staphylococcus aureus). The genus name starts with an upper-case letter, and the species name is all lower case. Both are italicized. Once an organism's name has been stated in full, use the abbreviated form thereafter. For the abbreviated form use the initial letter of the genus followed by the species name (e.g. P falciparum, S aureus). | |
| P value | Use an upper-case ‘P’ (not italic), and do not add a hyphen between the ‘P’ and the value | Numbers, statistics and units: statistical and mathematical presentation |