There are 2 types of reserved variable fragments described in ADaM: those that are reserved as variable suffix fragments and those that may used in naming ADaM variables. The suffix variables must be used as listed; if they appear at the end of a variable name, then the variable must match the fragment definition. The other fragments listed should be used in variable naming if possible but this does not preclude these fragments appearing in a variable name that has a different meaning.
Required Suffix Fragments for Use in Naming ADaM Variables
The following table lists standard suffix fragments (i.e., variable name fragments used as the last part of a variable name) that are required when naming variables in ADaM datasets, as defined in Section 2.9.5, Predefined Standard Variables for ADSL; Section 2.9.6, Predefined Standard Variables for BDS; and Section 2.9.7, Predefined Standard Variables for OCCDS. For these fragments, it is a requirement that the appropriate fragment be used whenever the concept applies and that the fragment is reserved to be used only for the corresponding concept. For example, a variable whose name ends in DT must contain a numeric date, and a variable created to contain a numeric date must have a name ending in DT.
Additional Fragments that May Be Used in Naming ADaM Variables
The following table lists additional standard reserved fragments to use as a guide when naming variables in ADaM datasets. This list should be used in addition to the list of timing fragments defined in Section 2.9.3.5, Variable Naming Fragments, and the fragments defined in the CDISC Non-Standard Variables Registry. It should be noted that some concepts have slightly different fragments in ADaM than in the TIG; the ADaM fragment takes precedence when creating an ADaM variable. When using fragments, the general rule is to use the fragment(s) that best conveys the meaning of the variable within the 8-character limit. This list of fragments is provided as a guideline, not as a requirement.