Is Any Particular Permalink Structure More SEO friendly than others?

I'm deciding on the Permalink structure I want to go with, but want to be certain i'm choosing the best structure.

Thanks!

yes,

lets say your writing an article for the health niche. lets say diarrhea symptoms
it would be better if hte permalink structure would be like this:

domain.com/health/diarrea-symptoms/

Do the manually blog commenting for your morey site is better be rank increase.

category/post-name
is pretty standard. But based on my experiences and others' who did tests on this there's NO statistically significant difference mate!

I always like to get my keywords in the URL for sure.

I think it boils down to whether or not to use categories in addition to the post title.

Personally, I don't use categories. I like direct URLS where it's URL.com/post-title

This is something I've never tested, just kind of intuited(wtf this is a word?), so it really is just preference and what I like to see...But I've always had an inkling of a feeling that a smart use of categories would propel a site beyond another site with just a title in the URL. I just have no idea how to test this, considering I still have no idea how to correctly use them for an added benefit over keyword titles. Perhaps use EMDs as the category names in your niche, but don't backlink heavily to a single EMD category, which would mean creating a bunch of niche targeted EMD categories?