| NI | neuraminidase inhibition; neurological improvement; neutralization index; no information; noise inde... |
|---|---|
| PEI | Patient Exit Interview; phosphate excretion index; physical efficiency index; polyethyleneimine |
| PRI | Pain Rating Index; phosphate reabsorption index; phosphoribose isomerase; placental ribonuclease inh... |
| PSI | posterior sagittal index; problem solving information; prostaglandin synthetic inhibitor; psychologi... |
| RRI | recurrent respiratory infection; reflex relaxation index; relative response index |