Answer: When the insurance company decides it is not.
The definition of screening, from a health prevention viewpoint, seems pretty straight forward: “a strategy used in a population to identify an unrecognized disease in individuals without signs or symptoms.” Typically these services are covered at 100%. However, insurance companies avoid appropriate payments for their members by changing the coding of a preventive service (which is covered 100%) into a diagnostic procedure, which is paid based on whatever the patient’s coverage allows. This change in coverage occurs because a polyp is found during the exam, which is of course, the whole point of doing the procedure: Screening and removing a polyp so that it never becomes cancer. Patients with high deductibles suddenly owe several hundred dollars in unexpected healthcare bills for a procedure they were told was covered. This is ethical and appropriate corporate policy?
And I can’t help but mention that the insurance company fancying itself a “Healthcare” company, promoting health and well-being, is the worst offender.
Subsequent colonoscopies that must be done five years later for individuals with polyps, instead of ten years, can arguably be called diagnostic. But changing the definition of a procedure solely to avoid paying for an appropriate screening exam, is another example of non-transparency, regardless of how well you explain it in the patient’s policy description.