For in vivo evaluation in sheep, the adherence module was incorporated into a modified IVR design consisting of a standard silicone pod-IVR [18, 19] containing no drug pods with the module inserted into an additional hollow tubular compartment added to span the center of the ring. The central compartment configuration, rather than embedding the electronics module in the outer silicone ring, was used for the initial sheep study to allow facile access to the circuit components during testing. Devices were programmed, powered, and placed in Sleep mode, and then inserted into the central compartment and sealed with silicone adhesive.