Comment:

From my point of view the ActivityDefinition resource will not be used exclusively by decision support solutions but rather from many workflow based products/solutions as well, such as workflow brokers, activities for medical collaboration, laboratory workflows etc. which may have no decision support component at all.

Even the Scope and Usage chapter of this resource states that:

An activity definition is a shareable, consumable description of some activity to be performed. It may be used to specify actions to be taken as part of an order set or protocol, or it may be used independently as part of a catalog of activities such as orderables.

which shows that the focus of this resource is not just bound to decision support but to many other processes like orders, or planning of workflows.

This resource also uses the patterns for request, event or definition which are created and maintained by the workflow group. Therefore I would propose to move this resource from the decision support group to the workflow group but of course retaining a close coordination when it comes to potential changes for this resource.

Summary:

Proposal to move the ActitvityDefinition resource from the decision support work group to the workflow work group.