Data Dictionaries and Metadata

Data dictionaries and metadata provide the structured framework for defining, describing, and managing clinical research data throughout the study lifecycle. A data dictionary specifies the characteristics and rules associated with individual data elements, including variable names, definitions, labels, data types, permissible values, coding, validation, and collection requirements, while metadata provides the broader contextual information needed to interpret and manage those data consistently. Together, they establish a common understanding of study data, support database development and quality control, promote standardization and traceability, and facilitate accurate analysis, data exchange, and long-term data reuse.