STUDYID, DOMAIN, and --SEQ are required in all domains based on one of the 3 general observation classes. Each general class domain must also include at least 1 of the following subject identifiers: USUBJID, SPDEVID, POOLID, SPTOBID, or GTREFID (in the GT domain only).

All identifier variables are allowed for any domain based on one of the 3 general observation classes, unless otherwise noted in the Usage Restrictions.

All Observation Classes—Identifiers