Erratum: The effect of Protandim® supplementation on athletic performance and oxidative blood markers in runners (PLoS ONE (2016) 11:8 (e0160559) DOI: 10.1371/journal.pone.0160559)

Abstract

The authors are correcting this article [1] to address queries and errors that were noted following its publication. Updated versions of Table 2 (S1 File) and Table 4 (S2 File) are included here, as errors in the corresponding tables in [1] were identified following publication. In the published article [1], when discussing adverse event outcomes (i.e. side effects), the Fisher’s exact test was used to assess the significance of the difference between the number of subjects that experienced at least one event of a given sign or symptom between groups. All pvalues were found to be non-significant. When a comparison of proportions between groups was performed (Chi-square, N– 1) [2], the authors found no significant differences between groups in the proportion of subjects experiencing at least one event from any sign or symptom (all p > 0.05) (S2 File). However, due to the limited sample sizes only substantial differences in proportions would be expected to be statistically significant in the analyses of adverse event outcomes; the trial was not designed with enough power to determine whether the proportions of adverse events in the two groups were statistically significant. The analysis of adverse events between groups was not a primary or secondary objective of the study. The adverse events were provided as preliminary data for future studies and for added interest to the reader.