Procedure designed to correct at least one measured value of a measured variable concerning a medium flowing through at least two measuring tubes, wherein the measured values are captured with a Coriolis measuring device, wherein the Coriolis measuring device has a first group (11.1) of measuring tubes and a second group (11.2) of measuring tubes each with at least one measuring tube to conduct the medium and, for each group, at least one vibration exciter and at least two vibration sensors, wherein each measuring tube is excited to vibrate by means of at least a vibration exciter, and wherein the vibrations of each measuring tube are measured by means of at least two vibration sensors, wherein the measuring tubes of different groups are decoupled from one another, wherein an electronic measuring/operating circuit of the Coriolis measuring device monitors, in each case, at least one of the following measured variables or, in each case, a measured variable which is derived therefrom by means of the first group and the second group: Phase difference between measuring signals of at least two vibration sensors, Resonance frequency, Vibration exciter current amplitude, Measuring tube vibration amplitude, wherein in a first procedural step, a credibility is determined for the at least one measuring tube of the first group and for the at least one measuring tube of the second group on the basis of at least one of the monitored measured variables, characterized in that, if a credibility requirement is not met by at least one of the measured variables monitored by means of the first group or second group of measuring tubes, measured values of the measured variables of the first group or of the second group are determined in a second procedural step depending on corresponding measured values of the measured variables captured by means of the at least one second group or first group. wherein each measuring tube is excited to vibrate by means of at least a vibration exciter, and wherein the vibrations of each measuring tube are measured by means of at least two vibration sensors, wherein the measuring tubes of different groups are decoupled from one another, wherein an electronic measuring/operating circuit of the Coriolis measuring device monitors, in each case, at least one of the following measured variables or, in each case, a measured variable which is derived therefrom by means of the first group and the second group: Phase difference between measuring signals of at least two vibration sensors, Resonance frequency, Vibration exciter current amplitude, Measuring tube vibration amplitude, wherein in a first procedural step, a credibility is determined for the at least one measuring tube of the first group and for the at least one measuring tube of the second group on the basis of at least one of the monitored measured variables, characterized in that, if a credibility requirement is not met by at least one of the measured variables monitored by means of the first group or second group of measuring tubes, measured values of the measured variables of the first group or of the second group are determined in a second procedural step depending on corresponding measured values of the measured variables captured by means of the at least one second group or first group. Phase difference between measuring signals of at least two vibration sensors, Resonance frequency, Vibration exciter current amplitude, Measuring tube vibration amplitude, wherein in a first procedural step, a credibility is determined for the at least one measuring tube of the first group and for the at least one measuring tube of the second group on the basis of at least one of the monitored measured variables, characterized in that, if a credibility requirement is not met by at least one of the measured variables monitored by means of the first group or second group of measuring tubes, measured values of the measured variables of the first group or of the second group are determined in a second procedural step depending on corresponding measured values of the measured variables captured by means of the at least one second group or first group.