| NFS | National Fertility Study; no fracture seen |
|---|---|
| NHS | Nance-Horan syndrome; National Health Service; National Hospice Study; normal horse serum; normal hu... |
| NNIS | National Nosocomial Infections Study |
| NWTS | National Wilms' Tumor Study |
| PAS | para aminosalicylate; Parent Attitude Scale; patient administration system; patient appointments and... |