MedDRA Web-Based Browser

APPENDIX A. ACRONYMS AND ABBREVIATIONS

Terminology Acronym	Thesaurus Name
COSTART ©	Coding Symbols for a Thesaurus of Adverse Reaction Terms
J-ART	Japanese Adverse Reaction Terminology
MedDRA	Medical Dictionary for Regulatory Activities
WHO-ART ©	World Health Organization Adverse Reaction Terminology

MedDRA Terminology Acronym	Definition
SOC	System Organ Class. The highest level in the hierarchy.
HLGT	High Level Group Term. Groups together HLTs that are related by anatomy, pathology, physiology, aetiology, or function.
HLT	High Level Term. Groups together PTs that are related by anatomy, pathology, physiology, aetiology, or function.
PT	Preferred Term. A single medical concept.
LLT	Lowest Level Term. A synonym, quasi-synonym, or sub-element of a PT.
SMQ	Standardised MedDRA Query. A grouping of MedDRA terms that relate to a defined medical condition or area of interest.

Please refer to the MedDRA Introductory Guide and the SMQ Introductory Guide for a more detailed description of MedDRA terminology definitions.