Abstract
Background Reproducibility of research findings has been recently questioned in many fields of science, including psychology and neurosciences. One factor influencing reproducibility is the simultaneous testing of multiple hypotheses, which increases the number of false positive findings unless the p-values are carefully corrected. While this multiple testing problem is well known and has been studied for decades, it continues to be both a theoretical and practical problem.
New Method Here we assess the reproducibility of research involving multiple-testing corrected for family-wise error rate (FWER) or false discovery rate (FDR) by techniques based on random field theory (RFT), cluster-mass based permutation testing, adaptive FDR, and several classical methods. We also investigate the performance of these methods under two different models.
Results We found that permutation testing is the most powerful method among the considered approaches to multiple testing, and that grouping hypotheses based on prior knowledge can improve power. We also found that emphasizing primary and follow-up studies equally produced most reproducible outcomes.
Comparison with Existing Method(s) We have extended the use of two-group and separate-classes models for analyzing reproducibility and provide a new open-source software “MultiPy” for multiple hypothesis testing.
Conclusions Our results suggest that performing strict corrections for multiple testing is not sufficient to improve reproducibility of neuroimaging experiments. The methods are freely available as a Python toolkit “MultiPy” and we aim this study to help in improving statistical data analysis practices and to assist in conducting power and reproducibility analyses for new experiments.
Footnotes
# Email addresses: satu.palva{at}helsinki.fi (Satu Palva), matias.palva{at}helsinki.fi (J. Matias Palva)