Simple portable device for sampling a whole day's urine and its application to hypertensive outpatients

To simplify 24-hour urine collection for epidemiological and clinical examinations, we devised a portable, semiautomatic urine sampling cup with divided partitions. The cup, 6.6 cm in diameter and 14 cm in height, is double-bottomed and has a pipe-shaped scale and a cock leading to the lower compartment. It is so devised that 1/m of the urine volume excreted into the upper compartment each time remains in the pipe scale, and then comes down into the lower compartment by manipulating the cock. The urine in the lower compartment remains when the urine in the upper compartment is discarded. The cup is carried in a vinyl bag. By repeating this manipulation. 1/m of the total urine excreted during 24 hours can be collected in the small cup (proportional sampling method). When the 24-hour urinary sodium excretion measured by the conventional method and that measured by this method were compared, the correlation coefficient (r) was 0.98, and the average variation was 2.0 +/- 10.8 (SD) mEq (n = 32). Use of this device for outpatients was convenient and enabled counseling on salt intake.