AHPREP-CBCS · CBCS — Certified Billing and Coding Specialist (NHA)·UnitAHPREP-CBCS · Unit 03Access: Premium

Unit 3: ICD-10-CM Diagnosis Coding

Prepare for Unit 3: ICD-10-CM Diagnosis Coding with practice questions covering 9 topics. Part of CBCS — Certified Billing and Coding Specialist (NHA) — build your knowledge and track your progress with AH Prep.

Questions
142
Topics
9
Access
Premium

What’s in it.

9 topics
  • Topic 01

    ICD-10-CM Structure — Tabular List, Index, and Conventions

    16 questions
  • Topic 02

    Official Coding Guidelines — Section I (General) Outpatient and Inpatient Rules

    15 questions
  • Topic 03

    Signs and Symptoms vs Confirmed Diagnoses

    15 questions
  • Topic 04

    Sequencing Principal and Additional Diagnoses

    15 questions
  • Topic 05

    Coding Chronic Conditions, Acute Exacerbations, and Combination Codes

    15 questions
  • Topic 06

    Coding Injuries — External Cause Codes, Episode of Care, and Trauma

    21 questions
  • Topic 07

    Coding Neoplasms — Behaviour, Morphology, and Metastasis

    15 questions
  • Topic 08

    Coding Pregnancy, Childbirth, and the Puerperium

    15 questions
  • Topic 09

    Z Codes — Factors Influencing Health Status and Contact with Health Services

    15 questions

Sample questions

3 of many

A few questions from this unit, with the answer and a full explanation. The complete bank is available when you start practising.

  1. A patient with type 2 diabetes uses long-term insulin. Which additional Z code is required alongside the diabetes code?

    • Z79.899 — Long-term use of other medication
    • No Z code is required; the E11 code alone captures insulin use
    • Z79.4 — Long-term (current) use of insulin
      Correct answer
    • Z51.81 — Encounter for therapeutic drug level monitoring
    Explanation

    Per ICD-10-CM Official Guidelines Section I.C.4, when a patient with type 2 diabetes uses long-term insulin, code Z79.4 (long-term use of insulin) is required as an additional code alongside the E11 diabetes code. This distinguishes a type 2 diabetic who requires insulin from one managed by oral agents or diet alone, which is clinically significant for care management and risk adjustment. Key takeaway: Z79.4 must be added whenever a type 2 diabetic is on long-term insulin therapy.

  2. What is the UHDDS definition of principal diagnosis for inpatient encounters?

    • The condition that received the most treatment during the inpatient stay
    • The admitting diagnosis documented at the time of hospital registration
    • The condition listed first in the attending physician's discharge summary
    • The condition established after study to be chiefly responsible for occasioning the admission
      Correct answer
    Explanation

    The Uniform Hospital Discharge Data Set (UHDDS) defines principal diagnosis as 'the condition established after study to be chiefly responsible for occasioning the admission of the patient to the hospital for care.' This definition emphasises that it is determined after diagnostic workup and may differ from the admitting diagnosis. Key takeaway: Principal diagnosis = condition responsible for the admission, established after workup — not necessarily the admitting complaint.

  3. What is the correct two-step process for assigning an ICD-10-CM code?

    • Search the patient's prior claim history for the most recently used code, then verify currency
    • Locate the code in the Alphabetic Index and assign it directly without further verification
    • First, locate the term in the Alphabetic Index to find a tentative code; then verify and finalise the code in the Tabular List
      Correct answer
    • First, look up the code in the Tabular List; then confirm it in the Alphabetic Index
    Explanation

    The ICD-10-CM Official Guidelines require a mandatory two-step process: (1) locate the main term in the Alphabetic Index to identify a tentative code, then (2) verify that code in the Tabular List to review all instructional notes. Coding directly from the Index without Tabular verification is explicitly prohibited. Key takeaway: Index first (tentative code), Tabular second (verify and finalise) — never skip either step.