Each observation can be described by a series of variables, corresponding to a row in a dataset or table.
Each row of the dataset represents a single observation and each column represents one of the variables.
Each dataset or table is accompanied by metadata definitions that provide information about the variables used in the dataset.
The set of Qualifier variables can be further categorized into five sub-classes: For example, in the observation, 'Subject 101 had mild nausea starting on Study Day 6,' the Topic variable value is the term for the adverse event, 'NAUSEA'.
The Identifier variable is the subject identifier, '101'.
In SDTM only the name, label, and type are listed with a set of CDISC guidelines that provide a general description for each variable used by a general observation class.
Comments are included as necessary according to the needs of individual studies.SDTM (Study Data Tabulation Model) defines a standard structure for human clinical trial (study) data tabulations and for nonclinical study data tabulations that are to be submitted as part of a product application to a regulatory authority such as the United States Food and Drug Administration (FDA).The Submission Data Standards team of Clinical Data Interchange Standards Consortium (CDISC) defines SDTM.The presence of an asterisk (*) in the 'Controlled Terms or Format' column indicates that a discrete set of values (controlled terminology) is expected to be made available for this variable.This set of values may be sponsor-defined in cases where standard vocabularies have not yet been defined (represented by a single *) or from an external published source such as Med DRA (represented by **).The Timing variable is the study day of the start of the event, which captures the information, 'starting on Study Day 6', while an example of a Record Qualifier is the severity, the value for which is 'MILD'.