Variable Naming Fragments

There are two 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, and 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 table below contains a list of 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 ADD LINK Section 3.1, ADaM Variable Conventions. 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.

Num	Fragment	CDISC Notes
1	GRy	Suffix used in names of grouping variables, where "y" refers to the grouping scheme or algorithm (not the category within the grouping). Note that GRy can be abbreviated to Gy when necessary to comply with the variable name length limit of 8 characters. The corresponding numeric version of the variable will use the suffix GRyN (or GyN if the Gy abbreviation is used). For more information on grouping variables see Section 3.1.1, General Variable Conventions. See Table 3.2.2 for examples of grouping variables.
2	FL	Suffix used in names of character flag variables, when the valid values of the variable are Y/null or Y/N/null. The corresponding numeric version of the variable will use the suffix FN. For more information on flag variables, see Section 3.1.1, General Variable Conventions, and Section 3.1.4, Flag Variable Conventions. See Table 3.2.3, Table 3.3.4.3.1, and Table 3.3.8.1 for examples of flag variables.
3	DT	Suffix used in names of numeric date variables. For more information on timing variables, see Section 3.1.2, Timing Variable Conventions. See Section 3.3.3, Timing Variables for BDS Datasets, for examples of timing variables.
4	TM	Suffix used in names of numeric time variables. For more information on timing variables, see Section 3.1.2, Timing Variable Conventions. See Section 3.3.3, Timing Variables for BDS Datasets, for examples of timing variables. Note that although ADaM variable ARELTM ends in TM, it is an exception, and is not a numeric time variable. In addition, the SDTM variables -- ELTM are not numeric time variables.
5	DTM	Suffix used in names of numeric datetime variables. For more information on timing variables, see Section 3.1.2, Timing Variable Conventions. See Section 3.3.3, Timing Variables for BDS Datasets, for examples of timing variables.
6	DTF	Suffix used in names of date imputation flag variables. Note that DTF can be abbreviated to DF to comply with the variable name length limit of 8 characters. For more information, see Section 3.1.3, Date and Time Imputation Flag Variables. See Section 3.3.3, Timing Variables for BDS Datasets, for examples of timing imputation variables.
7	TMF	Suffix used in names of time imputation flag variables. Note that TMF can be abbreviated to TF to comply with the variable name length limit of 8 characters. For more information, see Section 3.1.3, Date and Time Imputation Flag Variables. See Section 3.3.3, Timing Variables for BDS Datasets, for examples of timing imputation variables.
8	DY	Suffix used in names of relative day variables that do not include day 0. For more information on timing variables, see Section 3.1.2, Timing Variable Conventions. See Section 3.3.3, Timing Variables for BDS Datasets, for examples of timing variables.

Additional Fragments that May Be Used in Naming ADaM Variables

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Variable Naming Fragments