We know for a fact that the attribute check exists, there is no question there, since a character without any persuasion can pass failable checks (mostly when the relevant stat is high).
The question is wether the attribute gets improved by persuasion or if persuasion is just separate from it.
You will always have [attribute] persuasion options. Sometimes you will get options based on your tags. and very rarely you will get a persuasion option that involves BOTH a tag AND an attribute.
There is info on the wiki, if necessary.
Other than that, I don't think anyone did the full test yet, or if they did I didn't see the results.
