Abstract: The techniques described herein relate to computerized methods and apparatus for determining a dose injected into a user by one or more medication delivery devices. Data is accessed that is indicative of an injection event group that includes one or more injection events associated with one or more medication delivery devices. The injection event group is processed to determine the dose injected into the user based on one or more of whether the injection event is associated with a medication delivery device change, a dose size of one or more of the injection events, a position of one or more of the injection events in the injection event group, and/or a time period between one or more injection events to a next injection event in the injection event group.