Methods are disclosed for measuring an analyte concentration in a fluidic sample. Such methods further allow one to provide an error code or correct and/or compensate for interferents such as an antioxidant before providing an analyte concentration. The measurement methods utilize information obtained from test sequences having at least one DC block, such as a slow-ramped bi-polar waveform, where a closed circuit condition is maintained during the DC block. The methods use information relating to status of a redox mediator feature during the electrochemical analysis to provide an antioxidant failsafe if the antioxidant is interfering with the analyte concentration. Also disclosed are devices, apparatuses and systems incorporating the various measurement methods.