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Review
. 2009 Mar;106(11):184-9.
doi: 10.3238/arztebl.2009.0184. Epub 2009 Mar 13.

Study design in medical research: part 2 of a series on the evaluation of scientific publications

Bernd Röhrig  1 , Jean-Baptist du Prel, Maria Blettner
Affiliations
Review

Study design in medical research: part 2 of a series on the evaluation of scientific publications

Bernd Röhrig et al. Dtsch Arztebl Int. 2009 Mar.

Abstract

Background: The scientific value and informativeness of a medical study are determined to a major extent by the study design. Errors in study design cannot be corrected afterwards. Various aspects of study design are discussed in this article.

Methods: Six essential considerations in the planning and evaluation of medical research studies are presented and discussed in the light of selected scientific articles from the international literature as well as the authors' own scientific expertise with regard to study design.

Results: The six main considerations for study design are the question to be answered, the study population, the unit of analysis, the type of study, the measuring technique, and the calculation of sample size.

Conclusions: This article is intended to give the reader guidance in evaluating the design of studies in medical research. This should enable the reader to categorize medical studies better and to assess their scientific quality more accurately.

Keywords: measuring technique; quality; study; study design; study type.

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Figures

Figure 1
Figure 1
Connection between overall population and study population/data
Figure 2
Figure 2
Portrayal of the terms reliability (precision) and validity (trueness) using a target
See this image and copyright information in PMC

References

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MeSH terms