| PEFR | peak expiratory flow rate |
|---|---|
| PF | pair feeding; peak flow; perfusion fluid; pericardial fluid; periosteal fibroblast; peritoneal fluid... |
| PFG | peak flow gauge; pulsed-field gel electrophoresis |
| PIF | paratoid isoelectric focusing variant protein; peak inspiratory flow; proinsulin-free; prolactin-inh... |
| PIFR | peak inspiratory flow rate |