A diabetes management system having a reliable data management scheme is disclosed. The system comprises a plurality of devices, each device performing a different function relating to treatment of diabetes. Each device has a device identifier and generates data records. Each device includes a metadata generator configured to generate a metadata tag for a data record generated by the device. A metadata tag includes the device identifier of the corresponding device, a record identifier, and a source identifier indicating whether the record was originated by a human or the device. The system further includes a diabetes management device. When a device generates a new record, the metadata generator generates a new record identifier and a new metadata tag based on the new record identifier and the device identifier of the device. The first device propagates the new record and the new metadata tag to the diabetes management device.