CDISC ODM 1.3.0

(Source: CDISC Web site http://www.cdisc.org/odm)

The CDISC ODM standard facilitates the archival and interchange of the metadata and data for clinical research. ODM is a vendor-neutral, platform-independent format for the interchange and archival of clinical study data. ODM includes the clinical data and its associated metadata, administrative data, reference data, and audit information. All of the information that needs to be shared during setup, operation, analysis, and submission, as well as for long-term retention as part of an archive, is included in ODM.

CDISC ODM, Version 1.3.0, December 15, 2006

The SAS Clinical Standards Toolkit 1.4 supports this CDISC ODM 1.3.0 functionality:

As a general rule, the SAS representation of the CDISC ODM standard is patterned to match the XML element (data set) and attribute (column) structure of odm.xml. For example, consider this XML extract:

<ClinicalData StudyOID="P2006-101" MetadataVersionOID="101.01">
 <SubjectData SubjectKey="1000" TransactionType="Insert">
  <StudyEventData StudyEventOID="101.Screen">
   <FormData FormOID="101.DEMOG">
    <ItemGroupData ItemGroupOID="101.DM">
     <ItemDataString ItemOID="101.USUBJID">101-01-01</ItemDataString>
     <ItemDataString ItemOID="101.SEX">F</ItemDataString>
    </ItemGroupData>
   </FormData>
  </StudyEventData>
 </SubjectData>
</ClinicalData>

The highly structured nature of CDISC ODM data requires that any mapping to a relational format include a large number of data sets, with foreign key relationships to help preserve the intended non-relational object structure. In the SAS Clinical Standards Toolkit, foreign key relationships are enforced when validating the CDISC ODM data sets.

The table metadata for the 66 data sets and the column metadata for the 315 columns in those data sets that comprise the SAS representation of the CDISC ODM 1.3.0 standard are in this folder:

<global standards library directory>/standards/cdisc-odm-1.3.0-1.4/metadata.

Table metadata is in reference_tables.sas7bdat, and column metadata is in reference_columns.sas7bdat.

ODM 1.3.0 SAS Data Sets shows the CDISC ODM 1.3.0 data model that is the foundation for implementation in the SAS Clinical Standards Toolkit. No data set has more than one variable that acts as the key or index for that data set. The key variable name is appended with two asterisks (**). Some data sets do not have a key. A foreign key variable name is appended with two carat characters (^^). A foreign key variable name references the name of the data set for which it is a foreign key. The data set name is referenced within brackets. A required field is marked with an X between brackets, [X]. A required field is a field for which a non-nil and non-whitespace-only value must be provided for any observation in that data set.

Only the ODM data set, which contains valid values for the FileOID, CreationDateTime, and FileType variables, is needed to create a minimal, but valid, CDISC ODM-compliant XML document. This is based on the CDISC ODM standard, which is flexible. All table and column names are case sensitive. They must be specified exactly as shown.

In the SAS implementation of the relational data model, the keys are extended to define a unique record in every SAS data set. For example, a unique record in the EnumeratedItems data set is defined by the variables FK_CODELISTS and CODEDVALUE. These SAS data set keys are in the table metadata in the SAS Reference_Tables data set.

Starting in ODM 1.3.0, there are two forms of the ItemData element, which is the element used by ODM for transmitting clinical data item values. These two forms are untyped and typed. Here is an example of a typed ItemData element:

<ItemDataFloat ItemOID="ItemDef.OID.VS.VSSTRESN" TransactionType="Insert">76</ItemDataFloat>

Here is an example of an untyped ItemData element:

<ItemData ItemOID="ID.AETERM" Value="HEADACHE" />

Both of these data values are stored in the Value variable in the ItemData SAS data set. In the case of typed data, the ItemDataType variable in the ItemData SAS data set has the data type (for example, Float). In the case of untyped data, the ItemDataType variable in the ItemData SAS data set is null.

Typed and untyped data transmission should not be mixed within a single ODM file. However, in the example provided by the SAS Clinical Standards Toolkit, both types are part of the same example for demonstration purposes.

With the production release of the SAS Clinical Standards Toolkit 1.4, the CDISC ODM standard supports reading and representing in SAS a complete odm.xml file, building an odm.xml file, and validating the structure and content of the SAS representation of an odm.xml file. In addition, it validates the structural integrity of the odm.xml file.

It is this set of files, in whole or in part, that defines the CDISC ODM reference standard.