Medical Coding Books FAQs

• CPT® – Current Procedural Terminology
• ICD-9-CM – International Classification of Diseases, ninth revision, Clinical Modification.
• HCPCS – Healthcare Common Procedure Coding System
• ICD-10-CM – International Classification of Diseases, tenth revision, Clinical Modification
• ICD-10-PCS – International Classification of Diseases, tenth revision, Procedure Coding System

CPT® codes are used to describe the procedure or treatment the patient actually received.
ICD-9 and ICD-10 codes are the diagnostic codes and describe the patient’s medical condition or symptoms.
HCPCS codes are used to identify products, supplies, and services such as ambulance services and durable medical equipment, prosthetics, orthotics, and supplies (DMEPOS) when used outside a physician's office.

Learn more about the different code sets.

The three core coding books mentioned above are used in physicians’ offices, facilities, and payer organizations to perform accurate coding. The CPT® and HCPCS Level II code books are universal for both physicians and hospital organizations; the ICD-10 book is chosen based on the type of organization where you work or plan to work. If you work for a physician office or free-standing or facility-affiliated outpatient facility, you will only need the ICD-10-CM code book to document diagnoses. Inpatient facilities need both the ICD-10-CM and ICD-10-PCS books. The CM is used to document diagnoses that will be used to determine the patient’s diagnostic related grouping (DRG); the PCS book is used to document procedures performed in hospitals. You may also choose to add the Procedural Coding Expert book to your set of core books. This book contains the official AMA CPT^® codes and descriptions, CMS’ rules and guidelines, Relative Value Units (RVUs), HCC codes, and other valuable features, but excludes the AMA’s rules and guidelines. The Procedural Coding Expert book is a great supplement to your AMA CPT® book.

Every October 1, the upcoming year's ICD-10-CM and ICD-10-PCS code books are implemented for the following 12 months. All other codebooks such as CPT^® and HCPCS Level II are implemented in the healthcare industry every January 1.

View a full list of allowed reference materials for all AAPC exams.

Since the code sets for each coding book are updated every year, it's essential for coders to have the current year’s books to ensure accurate performance. Reporting wrong codes can lead to denied claim submissions and substantial penalization. It's clearly very important to get an education on the annual code set updates and to obtain new code books every year.

All AAPC exams are based on the current calendar year's code sets, so we strongly suggest you use the current year's books. The previous calendar year’s books may be used on an exam, but you would be at obvious disadvantage doing so. The upcoming year's books are not allowed for exam use. The exams are updated every January for the new code sets.

In other words, all exams administered in 2018 are based on the 2018 code sets, and we strongly recommend using the 2018 code books. Code books from 2017 may be used on the 2018 exams, but doing so is not ideal. Code books from 2019 may not be used on 2018 exams.

The expert version of ICD-9-CM and HCPCS Level II code books is the highest quality version and loaded with the most additional information. These books are enhanced with unique features often including additional tables and crosswalks, code alerts, icons and appendices, definitions, rules, and references. All these features help coders to eliminate costly errors and code more accurately and efficiently. The expert version is also equipped with spiral binding which makes it easier to use.

The next year's code books typically become available for preorder in March or April of each year. The ICD-9 and ICD-10 books ship in September, CPT® ships in October, and the HCPCS Level II and Procedural Coding Expert ship in December.

We have posted information and resources for the different code books on the individual code books' respective web pages.