Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2018 Aug 7;18(3):91-93.
doi: 10.1016/j.tjem.2018.08.001. eCollection 2018 Sep.

User's guide to correlation coefficients

Haldun Akoglu  1
Affiliations
Review

User's guide to correlation coefficients

Haldun Akoglu. Turk J Emerg Med. .

Abstract

When writing a manuscript, we often use words such as perfect, strong, good or weak to name the strength of the relationship between variables. However, it is unclear where a good relationship turns into a strong one. The same strength of r is named differently by several researchers. Therefore, there is an absolute necessity to explicitly report the strength and direction of r while reporting correlation coefficients in manuscripts. This article aims to familiarize medical readers with several different correlation coefficients reported in medical manuscripts, clarify confounding aspects and summarize the naming practices for the strength of correlation coefficients.

Keywords: Correlation coefficient; Cramer's; Interpretation; Lin's; Pearson's; Spearman's.

PubMed Disclaimer

Figures

Fig. 1
Fig. 1
Scatterplot of systolic and diastolic blood pressures of a study group according to sex.
See this image and copyright information in PMC

References

    1. Altman D.G., Altman E. Chapman & Hall/CRC; 1999. Practical Statistics for Medical Research.
    1. Definition of CORRELATION. Available from: https://www.merriam-webster.com/dictionary/correlation.
    1. Guyatt G. McGraw Hill Professional; 2014. Users' Guides to the Medical Literature: a Manual for Evidence-based Clinical Practice, 3E.
    1. Dancey C.P., Reidy J. Pearson Education; 2007. Statistics without Maths for Psychology.
    1. Chan Y.H. Biostatistics 104: correlational analysis. Singap Med J. 2003;44(12):614–619. - PubMed