| PERK | prospective evaluation of radial keratotomy [protocol] |
|---|---|
| PERS | Patient Evaluation Rating Scale |
| PRAISE | Prospective Randomized Amlodipine Survival Evaluation |
| PRECEDE | predisposing, reinforcing, and enabling causes in educational diagnosis and evaluation [model] |
| PREDICT | Prospective Randomized Evaluation of Diltiazem CD Trial |