1. A system for modeling a progression of a disease within a population, the system comprising: a plurality of point-of-care sample processing devices each comprising a programmable fluid transfer device, at least one optical detector, and a communications assembly; a central computing device operably in data communication with said plurality of point-of-care sample processing devices through the communications assembly on each of the sample processing devices, wherein the sample processing devices are positioned at distributed locations physically separate from the central computing device; a computer modeling component configured to generate a model of the progression of the disease within the population based on data received by the central computing device from the sample processing devices and data in (1) a static database component and (2) a dynamic database component and provide modeling results; wherein said central computing device electronically sends at least one protocol for running an assay based at least on said modeling results, to said plurality of sample processing devices without having to provide new sample processing devices to the distributed locations, wherein the protocol comprises at least one fluid transfer instruction to be performed by the programmable fluid transfer device.