snoll
New
When billing Medicare for more than one 87077 instead of using units we separate them out and add modifier 91 to each additional test done. So for 87077 x3 we bill it out as 87077 for the first one, 87077 91/QW for the second and 87077 91/QW for the third. Medicare is denying because of modifier used. Is 91 the correct modifier and does it matter if the QW or 91 is first on the claim?