What testing do science based facts get through to be validated?

[Alex K]

Yes, having something peer reviewed before publication is really just a minimal quality check, not replication. But results which have merely been peer reviewed but not replicated will usually not be universally viewed as canonically accepted results by the community. When other groups try to use a result as a basis for their further work, they will notice whether it works. For example, if Charpentier and Dudna had messed up their CRISPR Cas9 research, thousands of people would have noticed by now.because the method is used daily.

I agree there could be an indirect form of testing when attempting to use the results to further other research. But I can see two problems that arise if we lean too much on this. First, is that a paper's reliability becomes a measure of its popularity; meaning that papers that have been cited the most are the only ones that give us some confidence that they are reliable, whereas the vast majority of papers that have only been cited a handful of times cannot be seen as reliable. And I don't think scientists look to see how popular a paper is before they use it. Secondly, future research rarely hinges entirely on a single piece of previous work; they often review the entire literature on a subject and gather all the relevant papers in support of their own research project. This means that if their experiment is unsuccessful, you have as many variables to blame for the failure as you do papers in your reference section, and it is not immediately obvious which one is responsible (not to mention the fault could be with your own experiment design).

Well, finding out why, that is exactly what doing research is all about. Many a grad student will spend years wading through all relevant factors to determine where something goes awry. The only problem is that there is a bias against publishing negative studies which can bias the significance of published literature. That's why there are efforts to make pre-registration of studies mandatory.