Statistical Guidance for Reviewers of Toxicologic Pathology

Comparative Toxicogenomics of Glyphosate and Roundup Herbicides by Mammalian Stem Cell-Based Genotoxicity Assays and Molecular Profiling in Sprague-Dawley Rats

Whether glyphosate-based herbicides (GBHs) are more potent than glyphosate alone at activating cellular mechanisms, which drive carcinogenesis remain controversial. As GBHs are more cytotoxic than glyphosate, we reasoned they may also be more capable of activating carcinogenic pathways. We tested this hypothesis by comparing the effects of glyphosate with Roundup GBHs both in vitro and in vivo. First, glyphosate was compared with representative GBHs, namely MON 52276 (European Union), MON 76473 (United Kingdom), and MON 76207 (United States) using the mammalian stem cell-based ToxTracker system. Here, MON 52276 and MON 76473, but not glyphosate and MON 76207, activated oxidative stress and unfolded protein responses. Second, molecular profiling of liver was performed in female Sprague-Dawley rats exposed to glyphosate or MON 52276 (at 0.5, 50, and 175 mg/kg bw/day glyphosate) for 90 days. MON 52276 but not glyphosate increased hepatic steatosis and necrosis. MON 52276 and glyphosate altered the expression of genes in liver reflecting TP53 activation by DNA damage and circadian rhythm regulation. Genes most affected in liver were similarly altered in kidneys. Small RNA profiling in liver showed decreased amounts of miR-22 and miR-17 from MON 52276 ingestion. Glyphosate decreased miR-30, whereas miR-10 levels were increased. DNA methylation profiling of liver revealed 5727 and 4496 differentially methylated CpG sites between the control and glyphosate and MON 52276 exposed animals, respectively. Apurinic/apyrimidinic DNA damage formation in liver was increased with glyphosate exposure. Altogether, our results show that Roundup formulations cause more biological changes linked with carcinogenesis than glyphosate.

Statistical Reporting in Nursing Research: Addressing a Common Error in Reporting of p Values (p = .000)

PURPOSE

The confidence in a study will be reduced due to the incorrect representation of statistical results. However, it is unknown to what extent p values are incorrectly represented in published nursing journals. The study aims to evaluate the articles in 30 nursing journals in terms of the error in reporting of p values (p = .000).

DESIGN AND METHODS

This was a bibliometric analysis. All papers published in 10 leading nursing journals (between 2015 and 2019), the 10 bottom nursing journals (2019), and 10 selected key nursing journals (2019) indexed in the Science Citation Index Journal Citation Reports were reviewed to detect errors in reporting of p values (p = .000).

RESULTS

A total of 3,788 papers were reviewed. Notably, it was found that 93.3% (28/30) of the nursing journals contained incorrect representation of p values (p = .000). The reporting rate of these journals ranges from 0% to 57.1%, with an overall rate of 12.8% (486/3,788). In addition, the rate of incorrect representation of p values (p = .000) showed no statistically significant difference between different publication years (Χ² = 4.976, p = .290). However, the rate of reporting was different between study types, journals, and regions (p = .007, p = .020, and p < .001, respectively).

CONCLUSIONS

The incorrect representation of p values is common in nursing journals.

CLINICAL RELEVANCE

We recommend that both publishers and researchers be responsible for preventing statistical errors in manuscripts. Furthermore, various kinds of statistical training methods should be adopted to ensure that nurses and journal reviewers have enough statistical literacy.