Abstract: An apparatus and method for determining the concentration of a medically significant component of a biological fluid comprise providing a cell supporting a chemistry which reacts with the medically significant component. Placement of first and second terminals of the cell in contact with first and second terminals, respectively, of an instrument permits the instrument to assess the reaction. The instrument determines a first response of the cell to a first signal, and determines based upon the first response whether to proceed with the determination of the concentration of the medically significant component of the biological fluid. If the determination is to proceed, the instrument determines the type of sample that has been applied.

Abstract: An instrument (20) has a well (28a-b) for receiving a dry cell (75), an opening (78) through which a first connector (74) is exposed to the well (28a-b), and a boss (76) adjacent the opening (78). The boss (76) precludes the wrong terminal of the dry cell (75) from engaging the first connector (74) when the dry cell (75) is inserted into the well (28a-b) in incorrect orientation. A second connector (80) includes a base (81), a first leg (82) resiliently connected to and extending away from the base portion, a second leg (84) resiliently connected to and extending away from the first leg (82), and a third leg (86) resiliently connected to and extending away from the second leg (84) and toward the first leg (82). A display (42) for the instrument (20) has a lens (90) having a substantially transparent substrate with a polyurethane coating. The instrument housing has first and second portions.

Abstract: A biosensing meter is provided that determines a value of an analyte in a biological sample. The meter employs an algorithm for determining the analyte value, which value is dependent upon ambient temperature about the biological sample when it is present in a reaction zone. The biosensing meter includes a processor and a temperature sensor. The temperature sensor is positioned within the meter's structure and thereby exhibits a delayed response to changes in the ambient temperature. The meter performs a temperature estimation method to overcome the delayed temperature response. The method commences by the meter repetitively and periodically acquiring temperature readings from the temperature sensor when the biosensing meter is both in an on state and in an off state. When the meter is in the on state, the algorithm estimates the ambient temperature by employing at least two most recent temperature readings and extrapolating therefrom to achieve an ambient temperature estimate.

Abstract: A biosensing meter receives a sample strip that includes electrically isolated sense and excitation electrodes bridged by a reaction zone. When a drop of biological sample fluid is placed in the reaction zone, a plurality of fail/safe tests are performed. A drop size test is performed by a circuit that detects the size of the drop placed in the reaction zone. The circuit both detects that a drop has been placed in the reaction zone and further measures a test current level, after a delay, to determine that the drop size is sufficient to enable hydration of reactants in the reaction zone. Subsequently, during the reaction, a "delta" current change is measured at succeeding sample time. This test measures the difference between succeeding current samples during a measurement time. If each succeeding sample is not less than preceding sample by a delta value, a determination is made that the current is not monotonically decreasing and the test is aborted.