Hi Jennifer,
Both variables may be used for linking records in RS and TR domains. More often it's done by --LNKID variables.
SD1337 is an implementation of CDISC SDTM rule CG0024.
CDISC rule CG0022 is about --LNKGRP variable and covered by SD1338.
Kind Regards,
Sergiy
Pinnacle 21 ID is SD1337. This rule doesn't seem right, because the link between RS and TR is through --LNKGRP not LNKID, this is stated in RS assumption 5.