ICD 10 ICD — Questions and Answers

Question 1: In ICD-10-CM, what does the letter that begins each code generally represent?

The category of disease or body system (Correct answer)
The patient's age group
The hospital department
The billing tier

Correct answer: The category of disease or body system

The first character is always a letter that broadly indicates the chapter or category of the condition.

Question 2: What is the maximum number of characters an ICD-10-CM diagnosis code can contain?

5
6
7 (Correct answer)
8

Correct answer: 7

ICD-10-CM codes can be up to seven characters long for full specificity.

Question 3: Which character position in an ICD-10-CM code is reserved for the seventh-character extension such as encounter type?

First
Third
Seventh (Correct answer)
Second

Correct answer: Seventh

The seventh character captures details like initial encounter, subsequent encounter, or sequela.

Question 4: The seventh-character 'A' in an injury code most commonly indicates which encounter type?

Subsequent encounter
Sequela
Initial encounter (Correct answer)
Routine healing

Correct answer: Initial encounter

The letter 'A' designates the initial encounter while the patient receives active treatment.

Question 5: What does the seventh-character 'S' designate in ICD-10-CM injury coding?

Subsequent encounter
Sequela (Correct answer)
Severe injury
Surgical encounter

Correct answer: Sequela

The 'S' character identifies a sequela, a condition that arises as a direct result of a prior injury.

Question 6: When a code requires a seventh character but only has three to five characters, what must be used as a placeholder?

The letter X (Correct answer)
A zero
A dash
The letter Z

Correct answer: The letter X

The dummy placeholder 'X' fills empty character positions so the seventh character lands in the correct spot.

Question 7: ICD-10-CM is primarily used in the United States for which purpose?

Procedure coding in surgery
Diagnosis coding and reporting (Correct answer)
Pharmacy inventory
Nursing scheduling

Correct answer: Diagnosis coding and reporting

ICD-10-CM is the U.S. clinical modification used for reporting diagnoses across healthcare settings.

Question 8: In the ICD-10-CM coding convention, what does the abbreviation 'NOS' mean?

Not otherwise specified (Correct answer)
None of the system
Newly observed symptom
Number of services

Correct answer: Not otherwise specified

NOS means 'not otherwise specified' and corresponds to an unspecified code.

Question 9: What does the abbreviation 'NEC' indicate in ICD-10-CM?

Never edit code
Not elsewhere classifiable (Correct answer)
New encounter code
No existing condition

Correct answer: Not elsewhere classifiable

NEC means 'not elsewhere classifiable,' used when no specific code exists for a documented condition.

Question 10: An 'Excludes1' note in ICD-10-CM means what?

The two conditions can be coded together
The excluded code should never be used with the code above it (Correct answer)
Only one character is excluded
The code is obsolete

Correct answer: The excluded code should never be used with the code above it

Excludes1 is a pure exclusion meaning the two conditions cannot be reported together.

Question 11: An 'Excludes2' note in ICD-10-CM indicates what?

The condition is not part of the code but may be coded together if present (Correct answer)
The code is deleted
Two codes must always be combined
The diagnosis is excluded from billing

Correct answer: The condition is not part of the code but may be coded together if present

Excludes2 means the excluded condition is separate, and both codes may be assigned if both are present.

Question 12: In the Alphabetic Index, what do brackets [ ] around a code or term typically enclose?

Manufacturer notes
Synonyms, alternative wording, or explanatory phrases (Correct answer)
Deleted codes
Billing amounts

Correct answer: Synonyms, alternative wording, or explanatory phrases

Brackets enclose synonyms, alternative terms, or explanatory phrases in the index and tabular list.

Question 13: The instructional note 'Code first' in ICD-10-CM directs the coder to do what?

Sequence the underlying condition before the manifestation (Correct answer)
Always use the first code in the chapter
Code only the first encounter
Bill the first provider

Correct answer: Sequence the underlying condition before the manifestation

'Code first' indicates an underlying etiology must be sequenced before the manifestation code.

Question 14: What does a 'Use additional code' note instruct the coder to do?

Replace the primary code
Add a secondary code to fully describe the condition (Correct answer)
Delete an existing code
Use a placeholder X

Correct answer: Add a secondary code to fully describe the condition

This note signals that an additional code is needed to capture more detail, such as an infectious agent.

Question 15: A patient returns for routine follow-up during the healing phase of a fractured wrist. Which seventh character is most appropriate?

A (initial encounter)
D (subsequent encounter) (Correct answer)
S (sequela)
X (placeholder)

Correct answer: D (subsequent encounter)

The 'D' character is used for subsequent encounters during the routine healing or recovery phase.

Question 16: When laterality is required but the affected side is not documented, what should the coder do?

Assign the unspecified-side code (Correct answer)
Always choose the right side
Skip the code entirely
Use a placeholder X

Correct answer: Assign the unspecified-side code

If documentation does not state the side, an unspecified laterality code is assigned.

Question 17: For a patient seen for an injury caused by a fall, which type of code captures how the injury happened?

A Z code
An external cause code (V–Y) (Correct answer)
An R code
A C code

Correct answer: An external cause code (V–Y)

External cause codes (V00–Y99) describe the circumstances, like a fall, that led to the injury.

Question 18: A patient comes in solely for a routine general health checkup with no complaints. The appropriate first-listed code is most likely from which series?

R codes (symptoms)
Z codes (encounter for exam) (Correct answer)
S codes (injury)
I codes (circulatory)

Correct answer: Z codes (encounter for exam)

A Z code for an encounter for a general examination is reported when there is no active disease.

Question 19: When coding a suspected condition documented as 'rule out' in the outpatient setting, what does ICD-10-CM guidance direct?

Code the suspected condition as if confirmed
Code the signs, symptoms, or reason for the visit instead (Correct answer)
Do not code the encounter
Use only a placeholder code

Correct answer: Code the signs, symptoms, or reason for the visit instead

In outpatient coding, unconfirmed diagnoses are not coded; the documented signs and symptoms are reported instead.

Question 20: A combination code in ICD-10-CM is best described as a single code that does what?

Classifies two diagnoses or a diagnosis with an associated complication (Correct answer)
Combines two patients' records
Merges procedure and diagnosis
Replaces the seventh character

Correct answer: Classifies two diagnoses or a diagnosis with an associated complication

A combination code captures two diagnoses, or a diagnosis with a manifestation or complication, in one code.

Question 21: Which coding principle requires assigning codes to the highest level of detail supported by the documentation?

Laterality
Specificity (Correct answer)
Sequencing
Placeholder usage

Correct answer: Specificity

Coding to the highest level of specificity ensures the most accurate and complete code is selected.

ICD 10 ICD

In ICD-10-CM, what does the letter that begins each code generally represent?

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