The present invention provides a hand-held device of the type useful to perform an in vitro immunodiagnostic assay for an analyte of interest. In embodiments of the invention, the device incorporates a carrier for conducting the assay which comprises an array of pads including a sample pad, a narrow detection pad for detecting analyte, and a bridging pad coupled in flow communication therebetween. The device is provided with a housing adapted to deliver sample onto the carrier as a linear band having a width greater than the detection pad. In combination, these features yield a device that retains the sensitivity required for diagnostic accuracy, yet is improved in terms of cost and ease of manufacture.