How to distinguish a quality scientific article?

The higher the quality of the scientific articles used to make a state-of-the-art, the sounder the research will be.

It is possible to judge the quality of a scientific article by asking the following questions:

1. The first question to ask is whether the article has been reviewed by other experts. A review assesses that the reasoning is correct, that the way it is presented is correct and that there are no major flaws in the methodology.  Articles are regularly put online before this proofreading stage, therefore it is a work that has not yet been evaluated by the scientific community. An article is considered to be completed when it is published in a peer-reviewed scientific journal, hence with peer validation.
2. Not all scientific journals have the same rigour regarding the quality of published articles. The more serious a journal is, the higher its "impact factor" and the more one can have confidence in the quality of its scientific articles.
3. A recently published article may be more reliable than an older article on the same topic because it has the advantage of presenting information that has been updated. It is therefore important to refer to the date of publication of the articles to assess the reliability of the information.
4. The power of a discovery relies on the fact that other studies confirm what has been done; this is what scientists call "levels of proof". One study is interesting, but several studies that say the same thing is even more interesting!
5. It is strongly advised to look at the section about statistical processing of data when there is any. There is a methodological consensus on this type of study, and this research approach is shared by researchers from all domains, internationally.