This invention relates to a method for the rapidly determining the susceptibility of bacteria to antibiotics using histochemical detection of enzyme inhibition by the antibiotic. The spigot end of one pipe which is received within a bell coupler for an adjoining pipe terminates in a small annular bed-forming rib which forms a gasket bed that holds a gasket compressed against a radially extending gasket sealing surface of the bell coupler. Included are mechanisms for \u2018pass through\u2019 third party and insurance reimbursement for interpretive reports, insurance reimbursement for on-line access to pharmacogenetic information at the point of care, tools for market segmentation, and a conversion tool for capturing new subscribers. The data driver circuit includes a feedback capture circuit that captures each digit in substantially the same manner as the data capture circuit, and generates a latch control signal indicative of when each digit is latched. The signal amplitude applied at the first terminal controls optical output amplitude of the laser diode.