An output device includes a processor, wherein the processor executes a process. The process includes acquiring information including user identification information, device identification information for identifying a measuring device, a measurement value of each measurement type obtained by the measuring device, and measurement time of the measurement value, from different measuring devices. The process includes identifying information including measurement values associated with the same user identification information and the same measurement type, from the acquired information. The process includes determining whether time-series variation in the measurement values included in the identified information is different between a first measuring device and a second measuring device identified by the device identification information included in the identified information. The process includes outputting a result of difference when the time-series variation in the measurement values is different between the first measuring device and the second measuring device.
