Improved chromatographic strip binding assay devices are provided for determining the presence or amount of an analyte present in a patient sample. Assay label reagents interact with capture reagents immobilized in a testing region on the strip substrate to generate a visually detectable image indicative of the test result. The test result images include a minus sign (-) to indicate a negative test result for analyte which image is generated if the suspect analyte is absent in the patient sample and a plus sign (+) to indicate a positive test result for analyte which image is generated if the suspect analyte is present or is present at a pre-determined concentration in the patient sample. The immobilized capture reagents responsible for the location and configuration of the test result images are applied to the strip at an angled orientation with respect to the fluid flow direction of the strip to ensure that sharp substantially complete test result images are formed during performance of the assay. The devices provide substantially self-performing assays having inherently clear test results which are not subject to misinterpretation by the skilled or untrained user.