A general scheme of heads and side heads may call for the use of boldface type for first- and second-level heads and for first-level side heads in the text, although heading styles and formats vary among journals (see also 2.8, Manuscript Preparation, Parts of a Manuscript, Headings, Subheadings, and Side Headings). For example:
METHODS (level 1 head, flush left, bold caps)
Statistical Analysis (level 2 head, bold caps and lowercase)
Clustering Data.—(level 3 head or first-level side head, paragraph indent, run into the text, bold caps and lowercase).
Boldface may also be used in text to call out references to figures or tables.
Demographic data for the participants in the study are shown in Table 1.