Which style manual applies
The applicable style guide depends on the document’s recipient, sponsor and subject. A journal’s instructions or a sponsor’s corporate guide can establish the default, while specialist questions may require another manual.
Journal and recipient requirements
A manuscript should follow its target journal’s guidelines; using the manual specified by a journal or other recipient helps it meet that recipient’s requirements. When no target journal is defined, one recommendation for authors’ editors is to follow ICMJE rules.
The choice can also depend on readership, document type and the size of the writing team. Communicators commonly use one comprehensive manual for daily work, supplemented by dictionaries and other reference books.
Sponsor preferences in regulatory documents
For regulatory clinical documents, the AMA Manual of Style is a primary professional reference, but a sponsor’s corporate style guide takes precedence for stylistic questions where one exists. Editing nonclinical or chemistry, manufacturing and control materials may require other professional manuals, such as the American Chemical Society style guide.
During project planning, the team should establish the sponsor’s preferences for matters the corporate and AMA guides leave open. This helps consistency within and across documents, whether the project covers one document or a full submission.
At one CRO in 2014, AMA was the default style, an internal guide addressed matters such as bulleted-list punctuation and table formatting, and clients often supplied their own guides.
Scope across disciplines
Medical writers working in science and social science can move between styles more easily by understanding their similarities and differences. CSE covers sciences from astronomy and physics through chemistry and medicine, whereas AMA focuses on medicine. Chicago serves general-interest and book publishing, AP serves news, and AMA and APA concentrate on medicine and the social sciences respectively. Familiarity with AP style can help when editing some lay publications.
A 2013 comparison of then-current AMA, CSE, APA and Chicago manuals found common coverage of punctuation, capitalisation, abbreviations, spelling, plagiarism and copyright, with a basic understanding of grammar assumed. Differences concerned personal and place names, numbers, mathematical expression, statistics, data display, and the scope and focus of ethics coverage. AMA devoted 175 of 1,020 pages to its ethical and legal section, compared with 10 of APA’s 270 pages, although APA also addressed participant rights and researchers’ publication obligations elsewhere. CSE covered publication policy and copyright, data integrity and author and editor responsibilities; Chicago covered copyright law, permissions and publishing agreements.
One recommended approach across disciplines is to retain AMA as the primary guide for general language, publication and ethics questions, while consulting the relevant discipline’s guide for specific nomenclature or data-display questions. Manuals can complement one another: a journalist following AP style might use AMA for gene terminology and cancer staging.