Methods are disclosed for measuring substrate content in a specimen using a biosensor that includes two pairs of electrodes in a specimen supply path, where the methods include the steps of: (a) a first detecting step for detecting an electrical change in the first pair of electrodes; (b) a second detecting step for detecting an electrical change in the second pair of electrodes after the first detecting step; (c) a judging step for judging a shortage of specimen amount that is needed for measurement, when an electrical change is not detected in the second detecting step within a prescribed period of time after the first detecting step; (d) an indicating step for indicating a shortage of the specimen amount; and (e) a stopping step for stopping measurement of substrate content in the specimen once the shortage of specimen amount is indicated in the indicating step.