A method is provided that allows a subject to be diagnosed as having one of a variety of hypertensive states, including pre-eclampsia, based on the measurement of a plurality of factors including the level of soluble fms-like tyrosine kinase 1, an obesity factor and optionally one or more additional factors, which may be physiological parameters or biomarkers. The bus system includes a network controller adapted to be electrically coupled to each peripheral device and the franking machine, and adapted to permit data communications between each peripheral device and the franking machine, and between each peripheral device. A closure member, positioned within the chamber, is movable to close and open the inlet. The electronic device may have a housing in which the display is mounted. Once hydrostatic testing is complete, the center portion is detached from the end wall of the test cap and removed to allow access to the building drain.