The submitted manuscript is a privileged communication; reviewers must treat it as confidential. It should not be retained or copied. Also, reviewers must not share the manuscript with any colleagues without the explicit permission of the editor. Reviewers and editors must not make any personal or professional use of the data, arguments, or interpretations (other than those directly involved in its peer review) prior to publication unless they have the authors' specific permission or are writing an editorial or commentary to accompany the article.

The reviewer should have identified and commented on major strengths and weaknesses of study design and methodology The reviewer should comment accurately and constructively upon the quality of the author's interpretation of the data, including acknowledgment of its limitations. The reviewer should comment on major strengths and weaknesses of the manuscript as a written communication, independent of the design, methodology, results, and interpretation of the study. The reviewer should comment on any ethical concerns raised by the study, or any possible evidence of low standards of scientific conduct. The reviewer should provide the author with useful suggestions for improvement of the manuscript. The reviewer's comments to the author should be constructive and professional The review should provide the editor the proper context and perspective to make a decision on acceptance (and/or revision) of the manuscript.

to provide written assessment of the strengths and weaknesses of written research, with the aim of improving the reporting of research and identifying the most appropriate and highest quality material for the journal

Authorship

Animal experiments should require full compliance with local, national, ethical, and regulatory principles, and local licensing arrangements

Journals should have explicit policies as to whether these review board approvals must be documented by the authors, or simply attested to in their cover letter, and how they should be described in the manuscript itself

For those investigators who do not have access to formal ethics review committees, the principles outlined in the Declaration of Helsinki should be followed

Documented review and approval from a formally constituted review board (Institutional Review Board or Ethics committee) should be required for all studies involving people, medical records, and human tissues

Fabrication, falsification, concealment, deceptive reporting, or misrepresentation of data constitute scientific misconduct

This information was not explicitly stated in either article, but the sample and community description makes it clear that the participants of these studies are the same people, though the sample sizes differ slightly (ns = 85 and 86). However, this redundancy did not produce any analysis problems because the correlation matrix in the Grigorenko et al. (2001) article was not positive definite.