Why are there gaps in the artifact number sequences?

As you look down the list of numbered artifacts, you may notice a few gaps. For example, in v3.1 of the TMF Reference Model there is a gap between artifact 05.02.14 and 05.02.17. Where is 05.02.15 and 05.02.16?

In this example, the two “missing” artifacts were included in an earlier version of the Reference Model (up to v2) but were removed when v3 was published. The artifacts were removed when all artifacts related to local laboratories were moved from Zone 5 to Zone 8.

In general, when artifacts are removed during a revision, the remaining artifacts are not renumbered or re-used as that would have a major impact for those companies still using an older version of the Reference Model. Imagine if a CRO was using 05.02.15 for a Delegation of Responsibility Log but the sponsor was using 05.02.18 for the same document. It would make document exchange even more difficult than it is already!!

It has previously only been possible to identify why the gaps exist by comparing previous versions of the Reference Model and looking at the “tracked changes” spreadsheet. Since v3.1 however, we have been publishing Release Notes for the Reference Model so in future, it will be much easier to identify what the changes are for each Reference Model version.