A method of monitoring the properties of a biological or chemical sample. The method comprises: a) carrying out a plurality of different tests on the sample to generate corresponding test data, b) optionally carrying out a preliminary processing of the test data to generate partially processed data, c) storing the test data and/or partially processed data; d) causing a processing system to analyse a user-defined selection of the test data or partially processed data to generate result data relating to one or more properties of the sample; and e) subsequent to step (d), receiving a second user-defined selection of the test data or partially processed data, different from the first selection, and causing the processing system to analyse the second user-defined selection of the test data or partially processed data to generate second result data relating to one or more properties of the sample different from the properties corresponding to the first user-defined selection