Question: Where do I report a clinical trial number on an 837P form?
New York Subscriber
Answer: On the 837P, you should enter the clinical trial number in Loop 2300 REF02(REF01=P4). That’s the equivalent of Field 19 on the CMS-1500.
Add CT in front of the eight-digit clinical trial number.
Also be sure to include Z00.6 (Encounter for examination for normal comparison and control in clinical research program) on your claim and append modifier Q0 (Investigational clinical service provided in a clinical research study that is in an approved clinical research study) or Q1 (Routine clinical service provided in a clinical research study that is in an approved clinical research study) as appropriate on outpatient claims.