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PubMed · 9798082

Multiple correlations and Bonferroni's correction.

F Curtin·P Schulz
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Abstract

Correlation coefficients between biological measurements and clinical scales are often calculated in psychiatric research. Calculating numerous correlations increases the risk of a type I error, i.e., to erroneously conclude the presence of a significant correlation. To avoid this, the level of statistical significance of correlation coefficients should be adjusted. Threshold levels of significance for correlation coefficients were adjusted for multiple comparisons in a set of k correlation coefficients (k = 1, 5, 10, 20, 50, 100) by Bonferroni's correction. Significant correlation coefficients were then calculated according to sample size. The change in the threshold values of significance is larger when the number of correlations goes from 1 to 5 than when it goes from 50 to 100. A correlation coefficient, statistically significant at 5% when calculated alone, can be under the threshold level of significance when calculated even among a few other coefficients. Focusing on the most relevant variables or the use of multivariate statistics is advocated.

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Data Interpretation, StatisticalPsychiatric Status Rating ScalesPsychiatryResearch DesignSample SizeJournal Article

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BibTeXRIS

F Curtin, P Schulz. 1998-10-15. Multiple correlations and Bonferroni's correction.. https://doi.org/10.1016/s0006-3223(98)00043-2

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