Major Diagnostic Categories
The Major Diagnostic Categories (MDC) are formed by dividing all possible principal diagnoses into 25 mutually exclusive diagnosis areas.
The diagnoses in each MDC correspond to a single organ system or etiology and in general
are associated with a particular medical specialty.
Detailed information about MDCs is available from the Centers for Medicare and Medicaid Services.
- MDC 1 to MDC 23 are grouped according to principal diagnoses.
- Patients are assigned to MDC 24 (Multiple Significant Trauma) with at least two significant trauma diagnosis codes (either as principal or secondaries) from different body site categories.
- Patients assigned to MDC 25 (HIV Infections) must have a principal diagnosis of an HIV Infection or a principal diagnosis of a significant HIV related condition and a secondary diagnosis of an HIV Infection.
Detailed information about MDCs is available from the Centers for Medicare and Medicaid Services.
MDC |
Definition |
---|---|
0 | Ungroupable |
1 | Nervous System |
2 | Eye |
3 | Ear, Nose, Mouth, And Throat |
4 | Respiratory System |
5 | Circulatory System |
6 | Digestive System |
7 | Hepatobiliary System and Pancreas |
8 | Musculoskeletal System and Connective Tissue |
9 | Skin, Subcutaneous Tissue, and Breast |
10 | Endocrine, Nutritional, and Metabolic System |
11 | Kidney and Urinary Tract |
12 | Male Reproductive System |
13 | Female Reproductive System |
14 | Pregnancy, Childbirth, and Puerperium |
15 | Newborn and Other Neonates (Perinatal Period) |
16 | Blood and Blood Forming Organs and Immunological Disorders |
17 | Myeloproliferative Diseases and Disorders (Poorly Differentiated Neoplasms) |
18 | Infectious and Parasitic Diseases and Disorders |
19 | Mental Diseases and Disorders |
20 | Alcohol/Drug Use or Induced Mental Disorders |
21 | Injuries, Poison, and Toxic Effect of Drugs |
22 | Burns |
23 | Factors Influencing Health Status |
24 | Multiple Significant Trauma |
25 | Human Immunodeficiency Virus (HIV) Infection |