Table 1.

Identification of Split Specimens by Hierarchical Clustering

population sample		visit 2			visit 4			total
no.	name	no. of urine specimens	no. of split pairs	split pairs identified	no. of urine specimens	no. of split pairs	split pairs identified	no. of urine specimens	no. of split pairs	split pairs identified (%)
14	Aito Town	259	24	24	259	23	23	565	47	97.9
41	Chicago	315	24	23	315	24	23	678	46	95.8
21	Guangxi	278	23	17	278	24	17	603	34	70.8
all three samples		852	71	64	852	71	63	1846	127	88.2