A three-in-one apparatus for analyzing liquids, such as some body fluids, uses labeled molecular affinity binding, such as immunochromatography. The multi-functional diagnostic test device can detect an analyte, such as an antibody or antigen, which may indicate a particular condition. The multi-functional diagnostic test device provides multi-functional formats to apply in multiple different sampling methods, including the “dip”, “cassette” and “collection” formats. The diagnostic test device can accommodate a plurality of test strips, such as 18 test strips for analyzing up to 90 analytes.