Preparing Tables in Your Journal Articles

One the great problems that journal editors face today is that anyone with a computer and a word processing program can create their own tables and graphics to accompany their journal submissions. But most who do so are unaware of the typesetting protocols that go into proper table preparation and make tables that are too complex, too large, too poorly organized or too large. With a little bit of thought, it is possible to construct tables that easily convey information; that is, of course, the entire reason to have one.

Tables need to be prepared so that the information they contain are accurately understood. Tables should be used for the presentation of only certain kinds of information, including information where the numerical values are important, where there is a large amount of numerical data in a compact form, where a summary of information is needed, or where the information cannot easily be summarized in text form. The 6th edition of Scientific Style and Format (1) offers the following guidelines for tables:

- Make them complete enough that the reader does not need to continually refer to the text.

- Make them as simple as possible, and if it is not possible to make them simple, make them logical and orderly.

- There needs to be a logical basis for how you organize columns and rows.

- The units used in a table should be consistent with those in the text (which I note is a common error we find in tables).

- Do not provide the same information in both table and text format.

- Don’t make a table if you can easily explain the findings in a few lines of text.

When you prepare tables for publication, in general they are placed at the end of the manuscript, and are placed on individual new pages of the manuscript, no matter how small any given table might be. If you have 5 tables, that would take at least 5 pages to print. Each table should have a title, which is coordinated to the table number in the text. Each table should be numbered consecutively according to order of occurrence, and each should have its own call-out (that is, words that direct the reader to look at that particular table, ie, “See table 1.”). Do not use numbering where you have variants (Table 1a, 1b, 1c, etc). It is okay to use abbreviations in a table, but you should also use a footnote to let the reader know what the abbreviation means. Doing so saves space, which makes the table less costly to print. You do not need to use more than 2 significant digits in printing numerical data, and you should always provide the unit for the table so the reader knows exactly the meaning of the numerical data. Each column of entries should be aligned with its respective heading, either flush left or centered. If you have no number larger than 9999, you do not need to separate the digits with a comma, but if you go above 9999, you will have to do so (ie, 10,350). If you use decimal points, you should align on the decimal. Footnotes are used when the information they contain does not fit into the logical order of the table. Superscripts are recommended now, as numerics, not as symbols (such as asterisk, dagger, etc.). People understand the order better this way.

A lot of thought goes into table construction and it is not quite as easy as it may initially seem. Style guides such as the one referenced here can provide guidance, as can reference to the Vancouver Accords of the International Committee of Medical Journal Editors (2).

References

1. Style Manual Committee of the Council of Biology editors. Scientific style and format: the CBE manual for authors, editors and publishers, 6th edition. New York, NY; Cambride University Press, 1994:677
2. http://www.icmje.org/