Guidance for Datasets

Data represented in tabulation datasets will include the following per regulatory requirements, scientific needs, and standards in this guide:

• Data as originally collected or received (using controlled terminology where applicable) to support the submission.
• Data from external references relevant to the submission (such as a study protocol).
• Data assigned per conventions in the TIG.
• Data derived per regulatory and TIG conventions.

• Domain datasets based on the SDTM General Observations Classes will be named using the two-character code for the domain or using the applicable four-character code when a dataset is split.
• Supplemental Qualifier datasets will be named using convention SUPP concatenated with the two-character domain code or four-character code when a dataset is split (e.g., SUPPDM, SUPPFA, SUPPFACM).
• All other datasets will be named using the code for the domain or dataset and (e.g., DM, RELREC). 

Descriptive labels per this guide, up to 40 characters, will be provided as data variable labels for all variables, including Supplemental Qualifier variables.

When variable length is referenced in the TIG, this refers to the length in bytes of ASCII character strings.

• The maximum length of character variable is 200 characters which should not be used unless necessary.
• Applicants will consider the nature of the data and apply reasonable, appropriate lengths to variables. For example:
  • The length of flags will always be 1.
  • --TESTCD and IDVAR will never be more than 8, so the length can always be set to 8.
  • The length for variables that use controlled terminology can be set to the length of the longest term.

It is recommended that text data be submitted in text that is all upper case (e.g., NEGATIVE). Exceptions may include long text data (e.g., comment text). Values from controlled terminology or response values for QRS instruments specified by the instrument documentation should be in the case specified by those sources, which may be mixed case.

Missing values for individual data items will be represented by nulls. 

A domain dataset may be split into physically separate datasets to support submission when needed and as allowable by the regulatory authority. The following conventions must be adhered to when splitting domains into separate datasets:

• A domain based on a General Observation Class may be split according to values in variable --CAT. When a domain is split on --CAT, --CAT must not be null.
• The Findings About (FA) domain may be split based on the of the value in variable --OBJ.

To ensure split datasets can be appended back into one domain dataset:

1. 1. The value of DOMAIN must be consistent across the separate datasets as it would have been if they had not been split (e.g., LB, FA).
   2. All variables that require a domain prefix (e.g., --TESTCD, --LOC) must use the value of DOMAIN as the prefix value (e.g., LB, FA).
   3. --SEQ must be unique within USUBJID for all records across all the split datasets. If there are 1000 records for a USUBJID across the separate datasets, all 1000 records need unique values for --SEQ.
   4. When relationship datasets (e.g., SUPPxx, FAxx, CO, RELREC) relate back to split parent domains, the value of IDVAR will be from a variable with unique values for each observation. 

      1. When possible, the variable represented in IDVAR will have values from collected data (e.g., SPID, RECID), but variables with derived values may also be used (e.g., --SEQ).

   5. Permissible variables included in one split dataset need not be included in all split datasets.
      1. For domains with 2-letter domain codes, split dataset names can be up to 4 characters in length. For example, if splitting by --CAT, dataset names would be the domain name plus up to 2 additional characters (e.g., LBHM for LB if the value of --CAT is HEMATOLOGY). If splitting Findings About by parent domain, then the dataset name would be the domain code, "FA", plus the two-character domain code for parent domain code (e.g., "FACM"). The four-character dataset-name limitation allows the use of a Supplemental Qualifier dataset associated with the split dataset.
      2. Supplemental Qualifier datasets for split domains will also be split. The nomenclature will include the additional one to two characters used to identify the split dataset (e.g., SUPPLBHM, SUPPFACM). The value of RDOMAIN in the SUPP-- datasets would be the two-character domain code (e.g., LB, FA).
      3. In RELREC, if a dataset-level relationship is defined for a split Findings About domain, then RDOMAIN will contain the four-character dataset name, rather than the domain name "FA" (e.g., the value of RDOMAIN will be FACM).