Method and system for determining analyte levels

A method implemented using one or more processors, comprising:

• determining a rate of change of a monitored analyte level;
• anticipating a change in a direction of the rate of change of the monitored analyte level based at least in part on a change in characteristic information of a medication delivery device including one or more of a medication delivery rate, a medication delivery amount, or a medication delivery time period;
• evaluating received analyte related signals based on the anticipated change in the direction of the rate of change of the monitored analyte level;
• determining an estimated monitored analyte level based at least in part on the received analyte related signals;
• and
• filtering, using a rate variance filter, the received analyte related signals based on the determined rate of change of the monitored analyte level to generate filtered analyte related signals;
• wherein when the change in the characteristic information of the medication delivery device exceeds a predetermined threshold level, adjusting the rate variance filter from a predetermined setting to a modified setting to be responsive to changes in the monitored analyte level after a first predetermined time period lapses.