There are multiple definitions:

1. international prognostic index(English)

   • see follicular lymphoma
   • NHL, RCHOP
   • Prognosis

2. interpulse interval(English)

   • DOF, EMG, MUAP, PIF, PP
   • Electrophysiology

3. iliopsoas impingement(English)

   • has been associated with a distinct lesion on the anterior labrum
   • IFL, PIS
   • Musculoskeletal system, Pathology
   • https://doi.org…363546520944147