Patent ID: 8275437

Claim:
A system for monitoring glucose concentration in a host, the system comprising: a substantially continuous glucose sensor configured to produce sensor data indicative of a glucose concentration in a host; and a receiver configured to receive the sensor data from the substantially continuous glucose sensor and receive reference data from an in vitro single point glucose monitor, the reference data indicative of a measured glucose concentration in a biological sample from the host, wherein the receiver comprises: a processor module; and a computer readable memory comprising: instructions configured to cause the processor module to determine a rate of change of the glucose concentration in the host at a time corresponding to the measured glucose concentration in the biological sample; instructions configured to determine whether the rate of change is within a range of rates of change delimited by maximum normally sustainable rates of change of glucose in humans; instructions configured to cause the processor module to calibrate the sensor data, wherein the instructions are configured to allow the processor module to calibrate the sensor data using the reference data when the rate of change is within the range, but not allow the processor module to calibrate the sensor data using the reference data when the rate of change is outside the range instructions configured to cause the processor module to determine a time lag between the sensor data and the reference data based at least in part on the determined rate of change; and instructions configured to cause the processor module to form a matched data pair by matching one or more sensor data points of the sensor data with one or more data points of the reference data using the determined time lag, wherein calibrating the sensor data is based at least in part on the matched data pair.