I do care about how one becomes a successful solo practitioner in the field of California consumer law, but they don't exactly have databases about that.

Here's what I do:

Look at the job type you want. Look at professional websites of the people who have the jobs you want. Look at their CV's and see how they got there. If any of that info is expressible in a quantitative form (e.g. percent who went to top ten law schools) tabulate that.

You might notice "Oh, wait, most people who have the job I want have background X that I don't have!" (Different college major or whatever.) That might be evidence that you can't get that job; but before you start worrying, send someone an email and ask "How likely is it for me to get a job like yours with background Y instead of X?" It may be that your background is unusual but not a handicap.

Is it less rigorous than a scientific study? You bet. Is it better than nothing? Much.

If you have access to the attention of lots of professionals, a homemade poll can be very illuminating even if it's informal. For example, this survey about how novelists get published is more informative than most "how to be a writer" advice out there.