Medical diagnostic devices and methods

A method of operating a blood glucose meter (10), the method comprising: receiving and processing wirelessly transmitted time data with the blood glucose meter; generating a plurality of glucose concentration measurement values ​​from a plurality of tests performed with the blood glucose meter; correlating the plurality of glucose concentration measurement values ​​with particular points in time or time intervals during the day, wherein the correlated plurality of glucose concentration measurements establishes a range of glucose measurement values ​​associated with the particular point in time or interval of time; comparing a subsequently measured blood glucose concentration value derived from a subsequent test performed during the particular point in time or time interval with the range of glucose measurement values ​​associated with the particular point in time or time interval; and alerting a user to perform another test when the subsequently measured blood glucose concentration value falls outside the determined range of glucose measurement values.