21 ICD-10-CM Diagnosis Coding Practice Questions & Answers

1. 1. A coder recognizes the diagnostic term in the record and assigns a code directly from the Tabular List without consulting the Alphabetic Index. Why do the ICD-10-CM Official Guidelines treat this as a critical error?

   • A.The Alphabetic Index is the authoritative list, so the code it supplies is final and needs no Tabular check.
   • B.The Alphabetic Index must be searched first to locate the main term, and the Tabular List then verifies it.✓ Answer
   • C.The Tabular List alone is sufficient whenever the code carries no laterality choice and no seventh character.
   • D.Codes may be taken from either list, as long as the coder notes which list was used for the encounter.

   The Index locates the main term and the Tabular verifies the selection; Section IV.A calls starting the search in the Tabular the most critical rule violation, because the Index often does not give the complete code and laterality and seventh characters can be chosen only in the Tabular.

   Source: ICD-10-CM Official Guidelines, Section I.A.1 and Section IV.AReport a problem with this question

2. 2. A Tabular List entry carries an Excludes1 note naming a second condition, and the record documents both conditions as clearly related to one another. What does the Excludes1 note require?

   • A.Report both codes, because Excludes1 means the excluded condition is simply not included above.
   • B.Report both codes, sequencing the excluded code first because it identifies the underlying etiology.
   • C.Report only the excluded code, because an Excludes1 note redirects every such case to the code it names.
   • D.Report only one of the two codes, because Excludes1 means the conditions cannot be coded together.✓ Answer

   Excludes1 is a pure excludes note meaning NOT CODED HERE: the two codes are never reported together because the conditions represented cannot occur together, such as a congenital and an acquired form of the same condition.

   Source: ICD-10-CM Official Guidelines, Section I.A.12.a (Excludes1)Report a problem with this question

3. 3. A code carries an Excludes2 note naming another condition, and the record documents both the condition classified to that code and the excluded condition. What is correct?

   • A.Only the excluded condition's code is reported, because Excludes2 gives it priority over the code above.
   • B.Both codes may be reported together, because Excludes2 means the excluded condition is not part of the code above.✓ Answer
   • C.Neither code is reported until the provider documents which of the two conditions is clinically dominant.
   • D.Only the code above is reported, because Excludes2 means the two conditions cannot both be present.

   Excludes2 means NOT INCLUDED HERE: the excluded condition is not part of the condition the code represents, but a patient may have both at the same time, so reporting both codes together is appropriate when both are documented.

   Source: ICD-10-CM Official Guidelines, Section I.A.12.b (Excludes2)Report a problem with this question

4. 4. In the Alphabetic Index, a subterm gives two codes, the second of which is printed in square brackets. How must the pair be reported?

   • A.The bracketed code is the etiology and is sequenced first, ahead of the code printed before the bracket.
   • B.The bracketed code is a synonym for the first code, so only one of the two codes is actually reported.
   • C.The bracketed code is the manifestation and is always sequenced after the etiology code preceding it.✓ Answer
   • D.The bracketed code is optional and is reported only when the provider expressly links the two conditions.

   In the etiology/manifestation convention the Index prints the pair together with the etiology first and the manifestation in brackets, and the bracketed code is always sequenced second. Manifestation codes titled in diseases classified elsewhere may never be principal or first-listed.

   Source: ICD-10-CM Official Guidelines, Section I.A.13 (etiology/manifestation convention)Report a problem with this question

5. 5. A Tabular List code carries a Code also note. What does that note tell the coder about sequencing the two codes?

   • A.It requires the code named in the note to be sequenced first, exactly as a code first note does.
   • B.It requires the code named in the note to be sequenced second, as an additional secondary diagnosis.
   • C.It gives no sequencing direction, so the order depends on the circumstances of the admission or visit.✓ Answer
   • D.It makes the second code optional, so it is reported only when the payer's own edits require it.

   A code also note says that two codes may be required to fully describe the condition but supplies no sequencing instruction, so the coder sequences them according to the circumstances of the encounter. Confusing it with code first, which does dictate order, is a frequent error.

   Source: ICD-10-CM Official Guidelines, Section I.A.17 (code also note)Report a problem with this question

6. 6. A code requires a seventh character, but the code itself has only five characters. What makes the reported code valid?

   • A.The seventh character is appended right after the fifth character, giving a six-character code.
   • B.The placeholder X fills the sixth position so the seventh character sits in the seventh position.✓ Answer
   • C.The fifth character is repeated to fill the sixth position, and the seventh character follows it.
   • D.The seventh character is omitted, because it applies only to codes that already have six characters.

   A seventh character must always occupy the seventh position, so where the code is shorter the placeholder X fills the empty positions; poisoning codes are the classic example. A code that requires a seventh character is invalid without it.

   Source: ICD-10-CM Official Guidelines, Section I.A.5 (placeholder character) and I.A.4 (code structure)Report a problem with this question

7. 7. The provider documents a specific condition, but the classification contains no code for that exact condition. Which abbreviation applies and what does it mean?

   • A.NOS, not otherwise specified, used when the condition is specified but no specific code exists.
   • B.NOS, not on the schedule, used when the code was deleted from the classification in a prior year.
   • C.NEC, no established code, used when the documentation is too vague to support any code at all.
   • D.NEC, not elsewhere classifiable, used when the condition is specified but no specific code exists.✓ Answer

   NEC means not elsewhere classifiable and is the other specified situation: the record identifies a specific condition for which the classification has no specific code. NOS is the equivalent of unspecified and reflects a record that lacks the detail needed for a more precise code.

   Source: ICD-10-CM Official Guidelines, Section I.A.6 (abbreviations, NEC and NOS)Report a problem with this question

8. 8. In the Alphabetic Index a main term is followed by words in parentheses, and one of them contradicts the subterm the coder wants to use. How are the parenthetical words treated?

   • A.They are inclusion terms, so the code applies only to the conditions actually named in the parentheses.
   • B.They are nonessential modifiers, and the subterm governs when the two are mutually exclusive.✓ Answer
   • C.They are cross-references, so the coder must consult each parenthetical term before selecting a code.
   • D.They are essential modifiers, so the subterm may be used only if the record repeats them exactly.

   Words in parentheses are nonessential modifiers: they may be present or absent in the documentation without affecting code selection. When a nonessential modifier and a subentry are mutually exclusive, the subentry takes precedence, as with acute as a modifier of enteritis versus the subentry chronic.

   Source: ICD-10-CM Official Guidelines, Section I.A.7 (parentheses, nonessential modifiers)Report a problem with this question

9. 9. A record documents hypertension and stage 3 chronic kidney disease, with no statement from the provider linking the two. How does the classification treat this?

   • A.They are coded as related, because the classification presumes a causal link for with entries.✓ Answer
   • B.They are coded separately, because a causal link requires an explicit statement by the provider.
   • C.They are coded separately, because the presumption covers heart involvement but not the kidneys.
   • D.They are coded as related only after the coder queries the provider to confirm the relationship.

   The words with and in mean associated with or due to, and where they link two conditions in a code title, in the Index or in a Tabular note, the classification presumes a causal relationship. Hypertension with kidney involvement is one of those presumed links, so no provider statement is needed unless the record says they are unrelated.

   Source: ICD-10-CM Official Guidelines, Section I.A.15 (with) and Section I.C.9.aReport a problem with this question

10. 10. A short-term acute care hospital discharge summary lists probable pneumonia, with no confirmation anywhere in the record. How is this coded for the inpatient stay?

    • A.Code the signs and symptoms only, because a probable diagnosis is never coded as established.
    • B.Code pneumonia as though established, per the inpatient uncertain-diagnosis rule.✓ Answer
    • C.Code the condition and add a code showing the diagnosis was not confirmed at discharge.
    • D.Query the provider before coding, because probable cannot be coded in any care setting at all.

    Sections II.H and III.C direct that a diagnosis documented at discharge as probable, suspected, likely, questionable, possible, or still to be ruled out is coded as if it existed. The rule applies only to short-term acute, long-term care and psychiatric hospital inpatient admissions.

    Source: ICD-10-CM Official Guidelines, Sections II.H and III.C (uncertain diagnosis, inpatient)Report a problem with this question

11. 11. A physician office note ends with rule out cholecystitis for a patient seen for right upper quadrant pain. What does Section IV.H direct?

    • A.Code cholecystitis as confirmed, because uncertain diagnoses are coded as established at discharge.
    • B.Assign no diagnosis code until the diagnostic workup for the suspected condition has been completed.
    • C.Code the abdominal pain, because an outpatient encounter is coded only to the highest degree of certainty known.✓ Answer
    • D.Code cholecystitis first and the pain second, because the suspected condition is the reason for the visit.

    In hospital outpatient and physician office settings, terms such as rule out, probable, suspected, consistent with and working diagnosis are not coded. The encounter is coded to the highest degree of certainty known, which here is the documented sign, right upper quadrant pain.

    Source: ICD-10-CM Official Guidelines, Section IV.H (uncertain diagnosis, outpatient)Report a problem with this question

12. 12. For an inpatient stay, which of the following makes an additional condition reportable as an other diagnosis under Section III?

    • A.It appears anywhere in the record, since Section III calls for reporting every documented condition.
    • B.It was treated during an earlier admission and remains on the patient's problem list at this stay.
    • C.It was found on a laboratory report, since abnormal inpatient findings are reportable once identified.
    • D.It required clinical evaluation, treatment, diagnostic study, extended stay, or increased nursing care.✓ Answer

    Section III defines other diagnoses as conditions that affect patient care by requiring any one of five things: clinical evaluation, therapeutic treatment, diagnostic procedures, extended length of stay, or increased nursing care and monitoring. Inpatient abnormal findings are not coded unless the provider states their clinical significance.

    Source: ICD-10-CM Official Guidelines, Section III (reporting additional diagnoses) and III.BReport a problem with this question

13. 13. A patient is admitted with an acute myocardial infarction, and the record also documents chest pain, a symptom routinely associated with that condition. How is the chest pain handled?

    • A.It is not coded, because signs routinely integral to a disease process are not reported separately.✓ Answer
    • B.It is coded only when the provider states that the symptom prolonged the patient's length of stay.
    • C.It is coded second, because any documented symptom becomes reportable once it appears in the record.
    • D.It is coded first, because the symptom is what brought the patient to seek care at the hospital.

    Signs and symptoms that are routinely associated with a disease process are integral to it and are not assigned as additional codes unless the classification instructs otherwise. Symptoms that are not routinely associated with the condition are coded when they are present.

    Source: ICD-10-CM Official Guidelines, Sections I.B.4 and I.B.5 (signs and symptoms)Report a problem with this question

14. 14. A patient is seen for a contracture that resulted from a burn sustained two years ago. How are the codes assigned and sequenced?

    • A.Code the contracture first and the sequela code second; the acute burn code is not reported.✓ Answer
    • B.Code the acute burn first and the contracture second, since the burn caused the residual condition.
    • C.Code the sequela code first and the contracture second, since the sequela explains this encounter.
    • D.Code the contracture only; a sequela code may not be used once more than a year has passed.

    A sequela is the residual condition remaining after the acute phase has ended, and there is no time limit on reporting one. The residual is sequenced first and the sequela code second, and the code for the acute phase of the injury or illness is never reported with a late-effect code.

    Source: ICD-10-CM Official Guidelines, Section I.B.10 (sequela) and I.C.19.aReport a problem with this question

15. 15. A patient whose fracture was first treated at another hospital now presents to a different physician, who provides active fracture treatment at this visit. Which seventh character applies?

    • A.A, because the seventh character turns on active treatment being given, not on whether the provider is new.✓ Answer
    • B.S, because the visit follows the injury and addresses what remains after the initial treatment ended.
    • C.A plus an aftercare Z code, because the injury is now being managed by a different treating provider.
    • D.D, because care given by a physician who did not provide the original treatment is subsequent care.

    Seventh character A is assigned for every encounter at which the patient is receiving active treatment for the injury, whatever provider delivers it; D covers routine care during the healing phase after active treatment ends. Aftercare Z codes are never used for injuries, which use the injury code with D instead.

    Source: ICD-10-CM Official Guidelines, Section I.C.19.a (seventh characters A, D, S)Report a problem with this question

16. 16. After study, two interrelated conditions are each documented as potentially chiefly responsible for an inpatient admission, and no guideline, Index or Tabular note directs otherwise. What is correct?

    • A.The condition documented first in the discharge summary must be sequenced as principal.
    • B.The condition present on admission must be principal and the other reported as secondary.
    • C.The condition the provider designates may be sequenced as principal, since either qualifies.✓ Answer
    • D.The condition that consumed the most resources during the stay must be sequenced as principal.

    The UHDDS defines the principal diagnosis as the condition established after study to be chiefly responsible for occasioning the admission. When two interrelated conditions each meet that definition, either may be sequenced first unless the circumstances of admission, the therapy provided, or an Index or Tabular note directs otherwise.

    Source: ICD-10-CM Official Guidelines, Section II.B (two or more interrelated conditions) and the UHDDS definitionReport a problem with this question

17. 17. A patient develops bradycardia from a drug that was correctly prescribed and properly administered. How is the encounter coded?

    • A.Code the drug's poisoning code first and bradycardia second, because the drug produced the reaction.
    • B.Code bradycardia first, then the drug code with the character that identifies an adverse effect.✓ Answer
    • C.Code the underdosing code first and bradycardia second, because the dose taken caused the reaction.
    • D.Code bradycardia only; no drug code is assigned when the drug was taken exactly as prescribed.

    An adverse effect occurs when a drug is correctly prescribed and properly administered, and the nature of the adverse effect is sequenced first, followed by the drug code with the adverse-effect character. In a poisoning the order reverses: the poisoning code comes first and the manifestations follow.

    Source: ICD-10-CM Official Guidelines, Section I.C.19.e (adverse effects, poisoning, underdosing)Report a problem with this question

18. 18. An inpatient record documents severe sepsis with acute kidney failure due to the sepsis. What is the minimum correct code assignment?

    • A.The systemic infection first, then the severe sepsis code, then the acute organ dysfunction.✓ Answer
    • B.The underlying systemic infection alone, since severe sepsis is included in the infection code.
    • C.The severe sepsis code as principal, then the underlying infection and the organ dysfunction.
    • D.The acute kidney failure as principal, then the systemic infection and the severe sepsis code.

    Severe sepsis requires a minimum of two codes plus organ dysfunction coding: the underlying systemic infection first, then the severe sepsis code, then codes for the acute organ dysfunction. The severe sepsis code can never be a principal diagnosis, and neither can septic shock.

    Source: ICD-10-CM Official Guidelines, Section I.C.1.d.1 (severe sepsis)Report a problem with this question

19. 19. A patient with a known primary malignancy is admitted solely for treatment of anemia associated with that malignancy. How is the admission sequenced?

    • A.The anemia is the principal diagnosis and the malignancy is not reported for this admission at all.
    • B.The malignancy is the principal diagnosis and the anemia is reported only if it extended the stay.
    • C.The malignancy is the principal diagnosis, followed by the code for anemia in neoplastic disease.✓ Answer
    • D.The anemia is the principal diagnosis, since treatment this admission was directed only at the anemia.

    Admissions to treat a complication of a malignancy generally make the complication principal, but anemia associated with the malignancy is the stated exception: the malignancy is sequenced first, followed by the code for anemia in neoplastic disease.

    Source: ICD-10-CM Official Guidelines, Section I.C.2.c.1 (anemia associated with malignancy)Report a problem with this question

20. 20. A patient with a malignancy presents to a hospital outpatient department for a chemotherapy session only. What is the first-listed diagnosis?

    • A.The malignancy, because the neoplasm is what makes the therapeutic service medically necessary.
    • B.The code for the encounter for chemotherapy, with the malignancy reported as a secondary code.✓ Answer
    • C.The malignancy alone, because an encounter code is not reported when therapy is the only service.
    • D.The reason the patient was referred, with the chemotherapy encounter code reported second.

    For outpatient encounters for therapeutic services the reason for the encounter is first-listed, and chemotherapy, immunotherapy and radiation therapy are the stated exception in form only: the encounter-for-therapy Z code is first-listed and the diagnosis being treated is reported second.

    Source: ICD-10-CM Official Guidelines, Section IV.M (patients receiving therapeutic services)Report a problem with this question

21. 21. An inpatient condition is documented, but the record does not contain enough information for the coder to determine whether it was present at the time of admission. Which POA indicator applies?

    • A.A blank field, which reports that the condition could not be classified as present or not present.
    • B.W, which reports that the provider was unable to clinically determine whether it was present.
    • C.N, which reports that the condition was not present when the admission order was written.
    • D.U, which reports that the documentation is insufficient to determine whether it was present.✓ Answer

    U means the documentation is insufficient to determine whether the condition was present on admission, while W means the provider is unable to clinically determine it. The field is left blank only when the code appears on the exempt-from-reporting list, and the coder should query when the record is unclear.

    Source: ICD-10-CM Official Guidelines, Appendix I (Present on Admission reporting, indicators Y, N, U, W)Report a problem with this question

Practice questions based on the AHIMA Certified Coding Associate (CCA) Exam Content Outline, the ICD-10-CM and ICD-10-PCS Official Guidelines for Coding and Reporting, and the AHIMA Standards of Ethical Coding. This site is not affiliated with or endorsed by AHIMA. Code sets and their official guidelines are revised every year, so no question here keys a specific code value — always assign codes from the current code books, encoder and official guidelines in effect for the date of service, never from a practice test. Confirm current eligibility and exam requirements with AHIMA before you test. About the CCA credential →