Tables and figures

Aim

To present the results of your analysis in a clear and well-organised way

 

Documentation

  • Tables and figures as submitted in manuscripts.

 

Responsibilities

Executing researcher: To present the results in tables and figures in a clear way, including explanation of all abbreviations.
Project leaders: To advice and evaluate the executing researcher regularly on clear presentation of results in tables and figures.
Research assistant: N.a.

 

How To

It is important to present your results in a clear and well-organised way in tables and graphs, since this will make a significant contribution to the attractiveness of your article, poster or PowerPoint presentation. The choice of presenting results in a table or graph depends on the aim, number of variables, analysis methods and personal preferences. Some journals have a fixed policy on the number and design of tables and graphs, usually a maximum of 5 to 6 tables or figures.
Tables and graphs need to be produced in such a way that the reader is able to understand them without having to read any additional text. The title needs to be informative and the rows and columns in the tables or axes of the graphs need to be properly labelled. All abbreviations used need to be explained in full in a footnote below the table or graph. In general, tables are appropriate when you want to display the exact numbers from your analyses. Graphs are more appropriate for displaying trends or associations.
When presenting the inclusion of participants in an RCT, the majority of medical journals require a “patient flow chart”. This represents how many patients were approached, which ones were selected and excluded (and the exclusion criteria), the dropouts and the number of patients ultimately remaining who participated in the trial. Templates of the CONSORT flow diagram are available online.
Example flow chart
Conducting a systematic review, a flow chart should be used to map how many articles have been scanned, how many full text articles have been requested and how many articles have been included. A flow chart can also be useful in clarifying a complex treatment protocol.
The baseline table will include socio-demographic variables, such as age, gender and educational level. It will also contain the most important clinical characteristics describing your population, such as the severity of the disorder and general health status, and the baseline values of the determinants, outcomes and potential prognostic variables. Templates of the PRISMA flow chart are available online.
Effect estimates (e.g. average difference, relative risk or odds ratio) should always include a 95% confidence interval.
For (multiple) linear regression analysis the regression coefficient(s) (B) should be included, including the standard error(s) or a confidence interval. The p-value may also be included. However, this is not necessary if you present confidence intervals. Often odds ratio(s) and the 95% confidence interval are included in (multiple) logistic regression analyses.
For an association model (e.g. what is the effect of alcohol use on developing a cardiac infarction?) it is advisable to include both the raw effect estimates (e.g. odds ratio with 95% confidence interval), as well as any corrected effect estimates (e.g. corrected for age and gender).
For a prognostic model (e.g. what predicts levels of recovery after 6 months?) a measure of how well the model works needs to be included along with the regression coefficients, e.g. percentage variance explained or distinctive power (area under the ROC curve). For a prognostic model it is also necessary to properly describe the strategy used in selecting the variables and the criteria for including variables in the model.
Refer to the postgraduate course (EPIDM) in logistic regression for more information about the difference between association and prognostic models.

 

Appendices/references/links

  • Scientific style and format: the CBE manual for authors, editors, and publishers, 6th ed. Style Manual Committee, Council of Biology Editors. New York: Cambridge University Press, 1994.
  • Iverson C, Flanagin A, Fontanarosa PB, et al. American Medical Association manual of style: a guide for authors and editors, 9th ed. Hagerstown, Maryland, Lippincott Williams & Wilkins; 1997.
  • http://www.consort-statement.org/consort-statement/flow-diagram
  • http://prisma-statement.org/PRISMAStatement/FlowDiagram.aspx

 

V3.0: 5 Aug 2016: Revision guideline
V2.0: 12 May 2015: Revision format
V1.1: 1 Jan 2010: English translation
V1.0: 31 Jan 2008