MEDICAL NUTRITION TERMINOLOGY AND REGULATIONS IN THE US AND EUROPE: A SCOPING REVIEW BACKGROUND: Medical nutrition (MN) is comprised of parenteral nutrition (regulated in pharmaceutical legislation) and all forms of enteral nutrition that are regulated as "foods for special medical purposes" (FSMP), as defined by the European Commission. Standardized MN terms and definitions are needed to facilitate comparative and cost-effectiveness research of MN in disease management and health outcomes. OBJECTIVES: Conduct a scoping review to identify MN terminology, definitions and regulations in the United States and Europe. METHODS: The ISPOR Nutrition Economics Special Interest Group’s Medical Nutrition Working Group identified 19 MN terms and developed a systematic keyword search and inclusion/exclusion criteria to review relevant literature published from 1/2000 to 8/2015. The following databases were searched: Embase; MEDLINE; Cochrane Clinical Trials Registry; Centre for Reviews and Dissemination; the Cumulative Index to Nursing and Allied Health Literature, as well as pertinent professional and regulatory websites. Two-person teams extracted, reviewed and compared results for accuracy and completeness using a two-step screening process (i.e., title/abstract, then full-text review). RESULTS: Of the 1,687 titles/abstracts identified, 671 full-text articles were reviewed and 473 articles were included in the final analysis, including 222 records from 94 websites. Sixty-five percent of the articles mentioned MN terms, of which less than 35% provided a definition. The most common ICD codes/indications for MN were: symptoms, signs, abnormal clinical/laboratory findings (30%); endocrine, nutritional and metabolic diseases (15%), and digestive system diseases (13%). Less than 5% of the articles referenced a MN regulation, with few (<8%) reporting a health or nutrition economics analysis. CONCLUSIONS: MN terminology is not consistently defined and applied in the literature. This lack of clarity makes it challenging to interpret existing research findings and hampers effective assessment of the impact of MN on health outcomes and disease management.