| NTA | natural thymocytotoxic autoantibody; nitrilotriacetic acid; Nurse Training Act |
|---|---|
| OAA | Old Age Assistance; Older Americans Act; Opticians Association of America; oxaloacetic acid |
| OBRA | Omnibus Reconciliation Act |
| PDCA | plan-do-check-act |
| PDUFA | Prescription Drug User Fee Act |