Diagnosis (Dx)

What is diagnosis?

Diagnosis (Dx) is the process of information gathering and clinical reasoning to determine a patient's health problem.

Accurate diagnosis requires a medical professional--whether a nurse practitioner, physician, dentist, etc.--to correlate and identify patterns among signs and symptoms that may not be specific to a particular disease. Diagnosis usually begins following a patient's complaint, or when a clinician notices a deviation from the medical norm in the course of a routine exam.

During diagnosis, a medical professional will consider a patient's clinical history, conduct an interview and physical exam, and perform diagnostic testing. They may consult with other clinicians whose training and experience provide insight into certain diseases and conditions.

Diagnostic codes are used to classify and identify diagnoses associated with patient healthcare utilization and death.

What are diagnostic codes?

Diagnostic codes are combinations of letters and numbers that describe and classify diseases, disorders, symptoms and other reasons for patient healthcare utilization.

Diagnostic codes are used in both medical recordkeeping and billing systems.

The World Health Organization maintains the International Statistical Classification of Diseases and Related Health Problems (ICD), a medical classification list of internationally standardized diagnostic and procedure codes.

The 11th edition of the ICD (ICD-11) was released on January 1, 2022. The United States currently uses the 10th edition with a clinical modification (ICD-10-CM).