MedicationKnowledge is definitional: It provides knowledge about a medication as it appears in a SmPC or in a medication formulary. It does not speak about an acttual instance of this medication. Likewise, when a medication is linked to a device, it is not a specific instance of the device that is documented, but the kind or model of device. Therefore, MedicationKnowledge.device should reference DeviceDefinition (definition of the model of device) instead of Device (an actual instance of that model).

Change requested: 

MedicationKnowlege.device   0..   Reference(*DeviceDefinition)     replacing Device