The Medical Dictionary for Regulatory Activities (MedDRA) is an international classification of medical terminology used by regulatory agencies to describe medical events and issues (for example, adverse conditions) in all phases of the regulatory process (pre/post marketing, data entry, and so on). For a general overview on MedDRA, see the Understanding the Medical Dictionary for Regulatory Activities Pega Community Wiki article.
The MedDRA dictionary is organized with a five-level hierarchy. The highest or broadest level is System Organ Class (SOC), further divided into High-Level Group Terms (HLGT), High-Level Terms (HLT), Preferred Terms (PT) and finally into the most granular Lowest Level Terms (LLT).
System Organ Class (SOC)
High Level Group Term (HLGT)
High Level Term (HLT)
Preferred Term (PT)
Lowest Level Term (LLT)
Pega Foundation for healthcare provides MedDRA codes as one of the code sets in PegaHealthCodes Layer.