Generally (and I do mean, only generally, some places are different than others,) Quality Assurance means documentation: the review of documents for correct performing of the procedures, correct reporting of results, correct conclusions and the like. Quality Control are the members performing procedures: in my experience, HPLC for most pharmaceuticals, GC for some active ingredients, or excipients, particle sizers are important too. Moisture determination and some wet chemistry analysis may be required as well. UV spec methods may be used, if that's the way the method is written. TLC or Raman IR may be used as a sort of pass/fail test -- if an impurity shows up, no one really tries to figure out what or why, that batch of pills is just no good. But again, QC just reports that, QA decides.