1. A method of improving the determination of a physiological parameter based upon physiological signals, said method comprising the steps of: sensing a physiological signal indicative of the physiological parameter, said physiological signal having a desired portion and an undesired portion, said physiological parameter having a predetermined range of possible values; based upon said physiological signal, determining at least two possible indications of said physiological parameter based on at least two alternative calculations for said physiological parameter; and analyzing said at least two possible indications to determine a resulting indication that likely most closely correlates to the physiological parameter.