Hi, We started doing DAT in gel almost a year ago. We call the gel portion of the test a sensitive "DAT screen". The gel is a combination of the IgG and c3. If negative the test stops there. The positives reflex to both the IgG portion in gel and the C3 test in tube. We result as either positive for the complement portion, positive for the IgG portion, positive for both or negative. The docs are suppose to understand that the screening is more sensitive and a final negative is not out of the question.