False positive rates in Voxel-based Morphometry studies of the human brain: Should we be worried?

NEUROSCIENCE AND BIOBEHAVIORAL REVIEWS

卷:52

Review

Scarpazza, Cristina^1,2  Tognin, Stefania¹  Frisciata, Silvia^1,3  Sartori, Giuseppe³  Mechelli, Andrea¹ 

[1] Kings Coll London, Dept Psychosis Studies, Inst Psychiat Psychol & Neurosci, London SE5 8AF, England

[2] Univ Bologna, CSRNC, I-47023 Cesena, Italy

[3] Univ Padua, Dept Psychol, I-35131 Padua, Italy

关键词: Neuroimaging;    Voxel-based Morphometry;    False positive rate;    Unbalanced design;    Balanced design;   

DOI  :  10.1016/j.neubiorev.2015.02.008

来源: Elsevier

【 摘 要 】

Voxel-based Morphometry (VBM) is a widely used automated technique for the analysis of neuroanatomical images. Despite its popularity within the neuroimaging community, there are outstanding concerns about its potential susceptibility to false positive findings. Here we review the main methodological factors that are known to influence the results of VBM studies comparing two groups of subjects. We then use two large, open-access data sets to empirically estimate false positive rates and how these depend on sample size, degree of smoothing and modulation. Our review and investigation provide three main results: (i) when groups of equal size are compared false positive rate is not higher than expected, i.e. about 5%; (ii) the sample size, degree of smoothing and modulation do not appear to influence false positive rate; (iii) when they exist, false positive findings are randomly distributed across the brain. These results provide reassurance that VBM studies comparing groups are not vulnerable to the higher than expected false positive rates that are evident in single case VBM. (C) 2015 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

【 授权许可】

Free