An automated method for analyzing a plurality of samples within a housing of a self-contained system. The system is loaded with a plurality of samples, after which a first assay is performed on a first sample subset and a second assay performed on a second sample subset. The two assays include exposing the samples to a target capture reagent having a solid support for directly or indirectly immobilizing a target nucleic acid that may be present in one or more of the samples. The two assays may be performed with the same or different target capture reagents and target nucleic acids, but the receptacles for performing the exposing step have substantially identical geometries. Following the exposing step, an amplification reaction for amplifying a region of the target nucleic acid is performed with each sample. The amplification reactions of the two assays are performed in receptacles having different geometries.