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Published in: BMC Medical Research Methodology 1/2018

Open Access 01-12-2018 | Debate

Writing a discussion section: how to integrate substantive and statistical expertise

Authors: Michael Höfler, John Venz, Sebastian Trautmann, Robert Miller

Published in: BMC Medical Research Methodology | Issue 1/2018

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Abstract

Background

When discussing results medical research articles often tear substantive and statistical (methodical) contributions apart, just as if both were independent. Consequently, reasoning on bias tends to be vague, unclear and superficial. This can lead to over-generalized, too narrow and misleading conclusions, especially for causal research questions.

Main body

To get the best possible conclusion, substantive and statistical expertise have to be integrated on the basis of reasonable assumptions. While statistics should raise questions on the mechanisms that have presumably created the data, substantive knowledge should answer them. Building on the related principle of Bayesian thinking, we make seven specific and four general proposals on writing a discussion section.

Conclusion

Misinterpretation could be reduced if authors explicitly discussed what can be concluded under which assumptions. Informed on the resulting conditional conclusions other researchers may, according to their knowledge and beliefs, follow a particular conclusion or, based on other conditions, arrive at another one. This could foster both an improved debate and a better understanding of the mechanisms behind the data and should therefore enable researchers to better address bias in future studies.
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Metadata
Title
Writing a discussion section: how to integrate substantive and statistical expertise
Authors
Michael Höfler
John Venz
Sebastian Trautmann
Robert Miller
Publication date
01-12-2018
Publisher
BioMed Central
Published in
BMC Medical Research Methodology / Issue 1/2018
Electronic ISSN: 1471-2288
DOI
https://doi.org/10.1186/s12874-018-0490-1

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