The AMA created modifier 33 to allow providers to identify a preventive service for which, under the PPACA, there is no patient cost sharing. Use modifier 33 with a CPT code for a diagnostic/treatment service performed as a preventive service, such as a screening colonoscopy, even if a polyp is found and removed.
You may also use G codes intended for use for screening procedures for colorectal cancer screening:
o G0105: colonoscopy screening for individuals at high risk
o G0121: colonoscopy screening for individuals who are not high risk
o G0104: flexible sigmoidoscopy screening
When billing for preventive screening colonoscopy or sigmoidoscopy for any BCBSMA member, use modifier 33 or one of the G codes above so that the claim pays without any member cost share, according to the member’s benefits.
Do not use modifier 33 to bill for individuals receiving procedures due to signs or symptoms, or to rule out or confirm a suspected diagnosis. In this case, the procedure would be considered a diagnostic exam, not a screening exam. See the table on page 1 for coding examples. As always, be sure to check eligibility and benefits to determine appropriate member cost-sharing
National Guidelines
National guidelines recommend colorectal cancer screening starting at age 50 then every 10
years. However, more frequent or earlier screening is recommended for patients with certain
increased risk factors, such as a family history of colon cancer or personal history of polyps.
Screening in these situations will now also be covered when billed as a preventive service.**