A method for giving a measurement of quality for impedance based respiration monitoring is disclosed. The method comprises attaching a lead to a subject, the lead being connected to a monitor, and receiving a signal from the lead, the lead being used for impedance respiration monitoring； estimating amplitude of cardiovascular artifact, CVA, derived from the signal of the lead； estimating amplitude of respiration derived from the signal of the lead； calculating a quality factor for the lead based on the estimated amplitude of CVA and the estimated amplitude of respiration； and indicating the quality factor for the lead to the user via the monitor.
