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. Category III CPT codes are used for: → Emerging technology, services, and procedures
8. Which CPT modifier indicates a service was reduced or eliminated at the physician's discretion? → -52
9. The suffix '-plasty' means: → surgical repair
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. A patient is seen in the ED for acute exacerbation of COPD with acute bronchitis. How should these conditions be coded? → Code the combination code J44.0 (COPD with acute lower respiratory infection)
14. What is the 'clean claim' in the context of the revenue cycle? → A claim submitted without errors that requires no additional information for payment
15. A provider routinely waives patient copayments and deductibles without hardship assessment. This is considered: → Fraudulent — it misrepresents the actual charge and can induce overutilization
16. Which term describes billing for services NOT actually rendered? → Phantom billing (fraud)
17. In CPT coding, an 'unlisted procedure' code is used when: → No specific CPT code adequately describes the service performed
18. A choledochal cyst is a cyst originating from which structure? → common bile duct
19. Which letter begins HCPCS Level II codes for durable medical equipment (DME)? → E
20. When two or more physicians each perform a portion of a surgical team procedure, the appropriate modifier is: → -66
21. Which structure of the heart is responsible for initiating the electrical impulse that triggers each heartbeat? → Sinoatrial (SA) node
22. Which federal program monitors healthcare claims for fraud, waste, and abuse through data analysis and audits? → Recovery Audit Contractor (RAC) Program
23. The term 'dysuria' means: → painful urination
24. What does the abbreviation PRN mean? → when necessary
25. When coding an outpatient encounter for a condition that is documented as 'probable' or 'suspected,' what is the correct ICD-10-CM guideline? → Code the signs and symptoms, not the unconfirmed diagnosis
26. Which scenario best supports reporting modifier -57 with an E/M code? → E/M the same day as decision for major surgery
27. Under ICD-10-CM, how is hypertensive chronic kidney disease coded? → A combination code from category I12 linking hypertension and CKD
28. Chronic obstructive pulmonary disease (COPD) is primarily characterized by: → Persistent airflow limitation that is not fully reversible
29. Which HCPCS Level II code range covers ambulance and transportation services? → A0021–A0999
30. The prefix 'hepato-' refers to which organ? → Liver