Jack: I am a huge believer in checking HCQ levels in all our SLE pts. I started doing so in all pts not in remission and was quite shocked to find that around 35-40% of my patients who weren't in remission were poorly compliant ( a few "favorites" even had zero for levels after promising me to my face that they were taking it.) Confronting pts greatly improved adherence rates and subsequently better disease control in my clinic. I also started checking levels in pts in remission after seeing Michelle Petri's initial abstract that preceded the complete study here and use it now to lower doses if >1500 and in remission. Think of all the pts over time who have had an immunosuppressant added or steroids increased when all it would have taken was reeducation about HCQ after discovering HCQ poor adherence on blood levels. The most common answer from poorly adherent patients was, "I did not think it was that important nor effective, I never really felt that much better on it." I do feel HCQ blood levels should be the standard of care in managing SLE patients. (Disclosure: I speak for Exagen ... I do so because I am such a big believer in the test)