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NumConvention
1

To ensure compliance with SAS Version 5 transport file format and Oracle constraints, all ADaM variable names must be no more than 8 characters in length, start with a letter (not underscore), and be composed only of letters (A-Z), underscore ( _ ), and numerals (0-9). All ADaM variable labels must be no more than 40 characters in length. All ADaM character variables must be no more than 200 characters in length.

2

The lower-case letters "w", "xx", "y", and "zz" that appear in a variable name or label in this document must be replaced in the actual variable name or label using the following conventions:

    • The lower-case letter "w" in a variable name (e.g., PHwSDT, PxxSwSDT) is an index for the wth variable where "w" is replaced with a single digit [1–9].
    • The letters "xx" in a variable name (e.g., TRTxxP, APxxSDT) refer to a specific period where "xx" is replaced with a zero-padded two-digit integer [01–99]. The use of "xx" within a variable name is restricted to the concept of a period, and "xx" is not considered an index.
    • The lower-case letter "y" in a variable name (e.g., SITEGRy) refers to a grouping or other categorization scheme, an analysis criterion, or an analysis range, and is replaced with an integer [1–99, not zero-padded]. Truncation of the original variable name may be necessary in rare situations when a two-digit index is needed and causes the length of the variable name to exceed 8 characters. In these situations, it is recommended that the same truncation be used for both the character and numeric versions of the variables in a variable pair.
    • The lower-case letters "zz" in a variable name (e.g., ANLzzFL) are an index for the zzth variable where "zz" is replaced with a zero-padded two-digit integer [01-99]. Note that the "zz" convention represents a simple counter, while the "xx" convention represents a specific period.
    • If an indexed variable is included in a dataset, there is no requirement that the preceding variable(s) in the sequence be included. For example, a dataset might include ANL02FL but not ANL01FL.
3Any variable in an ADaM dataset whose name is the same as an SDTM variable must be a copy of the SDTM variable, and its label, meaning, and values must not be modified. ADaM adheres to a principle of harmonization known as "same name, same meaning, same values." However, to optimize file size, it is permissible that the length of the variables differ (e.g., trailing blanks may be removed). In many cases it makes sense to copy over a variable from an SDTM dataset. For example, the SDTM variable --SEQ may be useful for traceability. However, in other cases, it is also perfectly acceptable, and might be much better, to create an ADaM variable with a meaningful variable name and clear and unambiguous metadata. An SDTM variable may be somewhat meaningless when removed from its SDTM context. For example, the meaning of the SDTM variable DSDECOD may depend on other SDTM variables such as DSCAT and DSSCAT, and ultimately on how the data were collected and mapped to SDTM in a particular study; thus it may be better to create a clearly defined ADaM variable. In any case, whenever values are modified in any way, it is mandatory to do so in an ADaM variable, and it is prohibited to do so in a variable whose name is that of an SDTM variable.
4When an ADaM standard variable name has been defined for a specific concept, the ADaM standard variable name must be used, even if the content of an ADaM variable is a direct copy of the content of an SDTM variable. For example, in the creation of an ADaM dataset based on an SDTM LB dataset, even if AVAL is just a copy of LBSTRESN, the dataset must contain AVAL.
5 For variable pairs designated as having a one-to-one relationship within a specified scope (e.g., within a parameter, within a study), if both variables are present in the dataset and there exists a row in that scope on which both variables are populated, then there must be a one-to-one relationship between the two variables on all rows within the scope on which both variables are populated. The scope noted in this document should be considered the minimum level for the mapping; it does not preclude the producer from using a broader level of scope. For example, if a one-to-one relationship is specified as within a PARAM, the producer may elect to use the same one-to-one relationship across all PARAMs within the dataset or study. In addition, note that "within a parameter" means "within a parameter within a dataset."
6In a pair of corresponding variables (e.g., TRTP and TRTPN), the primary or most commonly used variable does not have the suffix or extension (i.e., N for numeric or C for character). The relevant suffix is used only on the name of the secondary member of the variable pair. For example, in the (TRTP, TRTPN) pair, the primary variable, TRTP, is character, but it is not named TRTPC. Similarly in the (APERIOD, APERIODC) pair, the primary variable, APERIOD, is numeric, but it is not named APERIODN. When a secondary variable is included in the dataset, then the primary variable must also be included. . If both variables of a variable pair are present, there must be a one-to-one relationship between the values of the two variables, as described in Item 5 above.
7In general, if an SDTM character variable is converted to a numeric variable in an ADaM dataset, then it should be named as it is in the SDTM dataset with an "N" suffix added. For example, the numeric version of the DM variable SEX is SEXN in an ADaM dataset, and a numeric version of RACE is RACEN. As stated in item 6, the secondary variable of the variable pair cannot be present in the dataset unless the primary variable is also present. Applying Item 6 to the variable pairs being described in Item 7, the numeric equivalent of the variable cannot be present in the dataset unless the character version is also present. If necessary to keep within the eight-character variable name length limit, the last character may be removed prior to appending the N. Note that this naming scheme applies only to numeric variables whose values have a one-to-one relationship to the values of the equivalent character variables. Note also that this convention does not apply to SDTM date/time ISO8601-formatted character variables converted to ADaM numeric *DT, *TM, and *DTM variables.
8Variables whose names end in FL are character flag (or indicator) variables with at most two possible non-missing values, Y or N (i.e., yes or no). The name of the corresponding numeric flag (or indicator) variable ends in FN. If the flag is included in an ADaM dataset, the character version (*FL) is required but the corresponding numeric version (*FN) can also be included. If both versions of the flag are included, there must be a one-to-one relationship between the values of the two variables, as described in Section 3.1.4, Flag Variable Conventions.
9Variables whose names end in GRy, Gy, or CATy are grouping variables, where "y" refers to the grouping scheme or algorithm (not the category within the grouping). For example, SITEGR3 is the name of a variable containing site group (pooled site) names, where the grouping has been done according to the third site-grouping algorithm; SITEGR3 does not mean the third group of sites. Within this document, CATy is the suffix used for categorization of ADaM-specified analysis variables (e.g., CHGCATy categorizes CHG).
10It is recommended that producer-defined grouping or categorization variables begin with the name of the variable being grouped and end in GRy (e.g., variable ABCGRy is a character description of a grouping or categorization of the values from the ABC variable for analysis purposes). If any grouping of values from an SDTM variable is done, the name of the derived ADaM character grouping variable should begin with the SDTM variable name and end in GRy (GRyN for the numeric equivalent) where y is an integer [1-99, not zero-padded] representing a grouping scheme. For example, if a character analysis variable is created to contain values of Caucasian and Non-Caucasian from the SDTM RACE variable, then it should be named RACEGRy and its numeric equivalent should be named RACEGRyN (e.g., RACEGR1, RACEGR1N). As described in Table 3.1.5.1, Gy can be used as an abbreviated form of GRy when the use of GRy would create a variable name longer than 8 characters. Truncation of the original variable name may be necessary when appending suffix fragments GRy, GRyN, Gy, or GyN.

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