Peer review

Peer review is the fundamental principle governing credibility and publication of a scientific paper.
Peers will be experts in the field.
Submitted papers are sent for critical evaluation and review by these experts. They check that published work has been reviewed properly and that current state of knowledge has been taken into account.
Peers check the following:

• Have they performed appropriate, robust and repeatable experiments?
• Have they presented clear and coherent data?
• Have they drawn appropriate conclusions that are supported by the evidence?
• Does the work actually add anything to what is already known?

Peer reviews are “double-blind” – the author does not know who the reviewer is and the the reviewer does not know who the author is. This removes prospect of bias for/against a paper and also possibility of influencing review outcome.
Reviewers have been through process to have their papers published. Their job is to make sure the paper is valid, credible, accurate and adds something to the pool of knowledge.