Abstract: An apparatus and method for flow and temperature analysis during collection of a urine sample, and for simultaneously maintaining the urine sample sterile. A disposable vessel for collecting the urine is mounted on a commode adapter, and includes a variable capacitor, with a capacitance value which varies with the amount of urine in the vessel. The variable capacitor forms a part of a capacitance bridge. A microprocessor controlled by a clock is used to periodically sample the varying capacitance value as fluid flows into the vessel, and thereby determine the flow rates of the fluid. A tube is provided which communicates with the interior of the vessel for drawing off a sterile sample of the urine for laboratory analysis, and a drain is provided which is operable without contacting the urine. Temperature sensing means are provided for detecting the temperature of the fluid as a function of time, comprising a thermistor or an infrared optical sensor.