Method of operating an automatic analysis apparatus and automatic analysis apparatus

A method of operating an automatic analysis apparatus for determining a parameter of a sample liquid, which depends on a concentration of at least one analyte in the sample liquid, based on a first measurement variable detected by the automatic analysis apparatus, wherein the automatic analysis apparatus comprises a measurement unit including an optical measuring transducer, the method comprising:

• providing a reaction mixture comprising the sample liquid in the measurement unit;
• detecting a first measured value of the first measurement variable using the optical measuring transducer, wherein the first measurement variable is at least one of an extinction, transmission, and intensity of light transmitted through the reaction mixture;
• when the detected first measured value indicates that the concentration of the at least one analyte in the reaction mixture is outside a measuring range of the automatic analysis apparatus for accurately detecting the first measurement variable, detecting a measured value of a second measurement variable of the reaction mixture using the optical measuring transducer, wherein the second measurement variable is an optical density of the reaction mixture, wherein the second measurement variable is different than the first measurement variable, and wherein the detecting of the second measurement variable has a greater measuring uncertainty than the first measurement variable;
• subsequently diluting the provided reaction mixture with a dilution liquid as a function of the detected measured value of the second measurement variable;
• and
• subsequently detecting a second measured value of the first measurement variable;
• and
• determining the parameter in the sample liquid based on the detected second measured value of the diluted reaction mixture via a measuring and control electronics of the automatic analysis apparatus such that the parameter is determined with greater accuracy than when based on the first measured value.