Last year, we used G0477-QW for all of our drug screens done in the office (we send them to an outside lab for confirmation). I have tried using 80305-QW and am getting denials stating that modifier is not appropriate with the code. Is there another modifier I should be using for the CLIA waved test or am I not able to bill for our drug screens anymore since we are CLIA waved? Any help would be great! Thanks!