There’s so much ‘evidence’ out there.
I’ve made this pyramid to help you when searching and reading about a new topic to gauge how reliable the conclusions you are drawing from a paper are, and which studies provide the strongest evidence.
A paper will usually (and should!) say in the abstract or early on in the introduction or method what style of study the paper used. Systematic reviews of randomised control trials provide the strongest evidence, whereas individual case reports are the weakest.
Hope this helps clarify a potentially mystifying landscape for those without a scientific background.
Any questions give me a shout!