Medical Coding Interview Questions
Common Interview Questions and Answers
Q: What are the three main medical code sets and when is each used?
A: ICD-10-CM for diagnosis coding in all settings (WHY the patient was seen). CPT for outpatient procedure coding (WHAT was done in physician offices and outpatient facilities). ICD-10-PCS for inpatient hospital procedure coding only. HCPCS Level II for supplies, DME, drugs, and ambulance services not covered by CPT.
Q: What is the difference between a CPC and CCS certification?
A: CPC (Certified Professional Coder) is AAPC's certification focused on outpatient physician office coding using CPT and ICD-10-CM. CCS (Certified Coding Specialist) is AHIMA's credential that covers both inpatient and outpatient settings with emphasis on hospital coding including ICD-10-PCS. CCS is generally considered more hospital-focused.
Q: What does "code to the highest level of specificity" mean?
A: It means you must assign the most precise code available that fully describes the condition. For example, do not code J18.9 (Pneumonia, unspecified) if documentation supports J18.0 (Bronchopneumonia) or J15.1 (Pneumonia due to Pseudomonas). The more specific code provides better data and ensures correct reimbursement.
Q: What is upcoding and why is it problematic?
A: Upcoding means billing a higher-level or more complex code than what the documentation supports. For example, billing a 99215 (high complexity visit) when only a 99213 (low complexity) is warranted. It is considered fraud under the False Claims Act and can result in fines up to $10,000 per claim plus three times the overpayment amount.
Q: How do you handle a diagnosis documented as "rule out pneumonia"?
A: It depends on the setting. In inpatient, you code uncertain diagnoses (probable, suspected, rule out) as if confirmed per ICD-10-CM official guidelines. In outpatient/physician office, you code the sign or symptom (e.g., cough, fever) rather than the uncertain diagnosis.
Q: What is a global surgical package?
A: The global surgical package bundles together the pre-operative visit, the surgical procedure, and post-operative care (0, 10, or 90 days depending on code) into a single fee. Billing separately for services included in the global package constitutes unbundling.
Q: What resources do you use to stay current with coding changes?
A: ICD-10-CM updates effective October 1 each year; CPT updates effective January 1. I follow CMS transmittals for Medicare policy changes, AHA Coding Clinic for ICD-10-CM guidance, CPT Assistant for CPT guidance, and AAPC/AHIMA newsletters and webinars.
Technical Skills Employers Look For
Additional Notes
Cloud and infrastructure tools evolve rapidly. Always cross-reference with the official documentation for the most current commands and best practices.