--BLFL is declared and no --LOBXFL is declared alongside it

Rule

VAR-002

Category

Variables changed

Basis

Confirmed Traceable to the published specification text cited below.

Detectability

Define-XML conclusive The Define-XML settles this one way or the other. No further evidence is needed to know whether it applies.

Finding type

Impact

Applies to

SDTMIG 3.2, 3.3, 3.4

What changes in v4.0

This dataset declares --BLFL, which Section 4.8 states has been removed from SDTMIG v4.0, and declares no --LOBXFL. Nothing in the Define-XML therefore carries the v4.0 representation of the last observation before exposure for this domain. What the Define-XML cannot show is whether the value exists anywhere else — a conversion pipeline may already compute an equivalent flag without declaring the column, and a study may have had no need of one. VAR-001 reports the removal itself; this rule reports the narrower case where no declared successor sits beside it.

What to do about it

Establish --LOBXFL for this domain: derive it if it does not exist, or declare and populate it if your conversion already computes an equivalent. Either way it is a timing derivation, anchored on the exposure reference start, so it needs EX or EC and agreement on which reference start applies. Do not treat it as a rename of --BLFL — where --BLFL encoded a study-specific analysis baseline, that definition belongs to the SAP and to ADaM's ABLFL and does not transfer. This rule, VAR-001 and CORE-002 are one baseline-transition workstream: they turn on the same reference start and the same baseline definition, so settle those once and work the three together.

What the scan can and cannot see

Both halves are Define-XML facts: --BLFL is declared and no --LOBXFL is declared in the same dataset. Whether the flag was ever derived, and from what, is not visible and is not claimed.