Medical billing desk

Chapter 1 · Infectious and parasitic diseases

Confirm the documented organism, infection site, and any required sequencing or additional-code instruction in the current Tabular List.

Chapter 2 · Neoplasms

Check the documented site, behavior, and encounter context; use the Neoplasm Table and Tabular List rather than inferring status.

Chapter 3 · Blood and immune disorders

Code only the documented disorder and specificity; review exclusions and any instructions about associated conditions.

Chapter 4 · Endocrine, nutritional, and metabolic diseases

Check combination-code, complication, and linkage instructions; do not infer a complication from medication or lab values alone.

Chapter 5 · Mental, behavioral, and neurodevelopmental disorders

Use the documented diagnosis and level of specificity; review applicable inclusion, exclusion, and sequencing notes.

Chapter 6 · Diseases of the nervous system

Confirm documented type, site, laterality, and any code-first or use-additional-code notes.

Chapter 7 · Diseases of the eye and adnexa

Check eye, side, and condition detail; do not select a more specific code than the record supports.

Chapter 8 · Diseases of the ear and mastoid process

Confirm the documented ear/site, side, and condition; follow the Tabular List instructions.

Chapter 9 · Diseases of the circulatory system

Review documented type, acuity, site, and any combination-code or sequencing instructions; do not assume a causal relationship.

Chapter 10 · Diseases of the respiratory system

Distinguish symptoms from established diagnoses and confirm acuity, type, and complications from documentation.

Chapter 11 · Diseases of the digestive system

Check site, acuity, and documented complications; follow all code-first and additional-code notes.

Chapter 12 · Diseases of the skin and subcutaneous tissue

Use documented location, laterality, and condition; verify any required depth or encounter detail.

Chapter 13 · Musculoskeletal and connective-tissue diseases

Check site, laterality, and documented etiology or status; use only specificity supported by the note.

Chapter 14 · Diseases of the genitourinary system

Confirm the documented organ/site and condition, and review any combination-code or sequencing instructions.

Chapter 15 · Pregnancy, childbirth, and the puerperium

When applicable, verify pregnancy status, trimester, episode, and chapter-specific sequencing rules in the official guidelines.

Chapter 16 · Certain conditions originating in the perinatal period

Confirm the documented perinatal condition and the applicable age/episode guidance.

Chapter 17 · Congenital malformations and chromosomal abnormalities

Code the documented congenital condition and detail; do not infer congenital origin from an adult diagnosis.

Chapter 18 · Symptoms, signs, and abnormal findings

Use symptom codes when appropriate under the official rules; do not substitute a symptom for a documented definitive diagnosis.

Chapter 19 · Injury, poisoning, and other consequences of external causes

Verify injury type, site, laterality, and required encounter character using the official guidelines and Tabular List.

Chapter 20 · External causes of morbidity

These codes add context to an event; check reporting requirements that apply to the payer, state, and setting.

Chapter 21 · Factors influencing health status and contact with services

Confirm the encounter or status is documented and follow any instruction to report an associated condition.

Chapter 22 · Codes for special purposes

Use only when the current code set and official instructions apply to the documented situation.

Chapter summaries are a study map only. The Official Guidelines and current code-set instructions control; annual updates can change requirements.

For CPT code lookup, use a current AMA CPT Professional publication or an employer/vendor platform authorized for your use. This app does not contain AMA-licensed CPT descriptions or verify CPT selection. A book purchase is not, by itself, permission to copy its content into software.

• Check the correct HCPCS release and service-date effective period; a matching code/descriptor does not prove that the service is covered or correctly selected.
• For drug codes, compare the specific drug and dosage unit in the HCPCS descriptor with the medication administration record and billed amount.
• Calculate units only from a documented dose and code-specific unit basis. Review discarded-drug reporting, JW/JZ requirements, NDC details, wastage, and payer policy separately when applicable.
• Do not infer a drug, dose, route, wastage, or number of units from a diagnosis or from a medication list alone.

Chapter 12 covers Medicare physician and nonphysician-practitioner billing and claims-processing requirements. It can help with Medicare billing workflow, but it is not the AMA CPT codebook, does not establish every payer's rules, and does not replace the date-specific CPT/HCPCS references.