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Comment & Response |

The Problem of Spurious Correlations Between Pairs of Brain Metabolite Values Measured in the Same Voxel With Magnetic Resonance Spectroscopy—Reply

Nina V. Kraguljac, MD1; Gary R. Cutter, PhD2; Charity Morgan, PhD2; Adrienne C. Lahti, MD1
[+] Author Affiliations
1Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham
2Department of Biostatistics, University of Alabama at Birmingham
JAMA Psychiatry. 2014;71(3):339-340. doi:10.1001/jamapsychiatry.2014.22.
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In Reply Dr Maddock’s letter in response to our recent article1 suggests that it is statistically problematic to report correlations between ratios without accounting for spurious correlations. Spurious correlations were first described by Pearson, who showed that correlations between 2 ratio variables that have the same denominator may be present, even when the original variables from which the ratios were derived are uncorrelated.2


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March 1, 2014
Richard Maddock, MD
1Imaging Research Center, Department of Psychiatry, University of California–Davis, Sacramento
JAMA Psychiatry. 2014;71(3):338-339. doi:10.1001/jamapsychiatry.2013.4343.
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