| OHI | Occupational Health Institute; operative hypertension indicator; oral hygiene index; Oral Hygiene In... |
|---|---|
| AAA | abdominal aortic aneurysm/aneurysmectomy; acne-associated arthritis; acquired aplastic anemia; acute... |
| AAAI | American Academy of Allergy and Immunology |
| AACIA | American Association for Clinical Immunology and Allergy |
| ACAAI | American College of Allergy, Asthma and Immunology |