There are multiple definitions:

1. incidence rate ratio(English)

   • a relative difference measure used to compare the incidence rates of events occurring at any given point in time. Sometimes called an incidence density ratio or incidence rate ratio
   • ASTS, NIH, ACL, ACLR, RTS, aIRR
   • Epidemiology, Ratio-based metric
   • https://doi.org…43.2011.03878.x
   • https://doi.org…363546514530088

2. incidence rate reduction(English)

   • MenACWY-TT, MenWVE, IMD, MenACWY, NIP, VE
   • Prognosis, Immunology
   • https://doi.org…15.2023.2251825

3. internal root resorption(English)

   • a particular category of pulp disease characterized by the loss of dentine as a result of the action of clastic cells stimulated by pulpal inflammation
   • Dentistry, Pathology
   • https://doi.org…155/2013/929486