COC Cheat Sheet 2026

The 30 highest-yield COC facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. Which modifier is appended to a CPT code to indicate a bilateral procedure? → -50
2. Which of the following best describes 'medical necessity' in coding compliance? → Services must be appropriate to the diagnosis, evidence-based, and not excessive
3. Which modifier indicates that a service or procedure has been reduced or eliminated at the physician's discretion? → -52
4. Which modifier is appended to a CPT code to indicate that a procedure was performed on the right side of the body? → -RT
5. Which ICD-10-CM chapter contains codes for external causes of morbidity? → Chapter 20 (V00–Y99)
6. What is the purpose of CPT modifier -59? → Distinct procedural service not normally reported together
7. Modifier -76 is used to report: → Repeat procedure by the same physician
8. Category III CPT codes are used for: → Emerging technology, services, and procedures
9. Which CPT modifier indicates a service was reduced or eliminated at the physician's discretion? → -52
10. A patient is diagnosed with deep vein thrombosis (DVT) of the popliteal vein. The popliteal vein is located in which body region? → Behind the knee
11. Modifier -57 is used when an E/M service results in the initial decision to perform: → A major surgery (90-day global)
12. A patient receives 250 mg of a drug, but the HCPCS code describes 50 mg per unit. How many units are reported? → 5
13. What is the 'clean claim' in the context of the revenue cycle? → A claim submitted without errors that requires no additional information for payment
14. A provider routinely waives patient copayments and deductibles without hardship assessment. This is considered: → Fraudulent — it misrepresents the actual charge and can induce overutilization
15. Which term describes billing for services NOT actually rendered? → Phantom billing (fraud)
16. In CPT coding, an 'unlisted procedure' code is used when: → No specific CPT code adequately describes the service performed
17. A choledochal cyst is a cyst originating from which structure? → common bile duct
18. Which letter begins HCPCS Level II codes for durable medical equipment (DME)? → E
19. When two or more physicians each perform a portion of a surgical team procedure, the appropriate modifier is: → -66
20. Which structure of the heart is responsible for initiating the electrical impulse that triggers each heartbeat? → Sinoatrial (SA) node
21. Which federal program monitors healthcare claims for fraud, waste, and abuse through data analysis and audits? → Recovery Audit Contractor (RAC) Program
22. What does the abbreviation PRN mean? → when necessary
23. Which scenario best supports reporting modifier -57 with an E/M code? → E/M the same day as decision for major surgery
24. Chronic obstructive pulmonary disease (COPD) is primarily characterized by: → Persistent airflow limitation that is not fully reversible
25. Which modifier is appended when a procedure or service is greater than usually required? → -22
26. Which HCPCS Level II code range covers ambulance and transportation services? → A0021–A0999
27. The prefix 'hepato-' refers to which organ? → Liver
28. What is the function of Peyer's patches? → They help to protect against invading microorganisms.
29. In outpatient coding, how should a patient encounter for screening colonoscopy where a polyp is found and removed be coded? → Code the screening Z-code first, then the polyp finding
30. For office E/M codes, which of the following is NOT a recognized category of problems under the 2021 MDM guidelines? → Chronic illness with only marginal follow-up