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IMS Reference Materials

To understand the structure of the database and the data items included, three documents are needed:

    Codes List — Identifies all the codes for each coded variable and their meanings.

    Data Dictionary — Defines each variable; contains the variable name, table name, variable definition, units, name of the codes list used, and range check information used in the QC process.

    Schema — Identifies all data elements grouped by the table in which they are found in the database; it contains the variable names, their field location in a record, and their format (numeric, character).

These three documents are in ASCII format and occupy 5 MB of space. To download the zip file (463 KB), click here.



 

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