1. A method comprising the following steps: (a) determining a first period of time that an individual has been active based on motion data for a dosimeter worn by the individual and time data associated with the motion data, and (b) reporting the first period of time the individual has been active via a visual display device and/or via saving the first period of time the individual has been active to a storage medium, wherein the dosimeter comprises one or more motion sensors for generating the motion data.