Table 5. Sensitivity of different sampling efforts to detect S. mekongi and O. viverrini infections.

	Sensitivity of different Kato-Katz thick smear sampling efforts
Helminth species	Baseline survey (n = 90)				Days 28–30 posttreatment follow-up (n = 66)
	1 stool1 smear	1 stool3 smears	3 stools1 smear	3 stools3 smears	1 stool1 smear	1 stool3 smears	3 stools1 smear	3 stools3 smears
	n (%)	n (%)	n (%)	n (‘gold’ standard)	n (%)	n (%)	n (%)	n (‘gold’ standard)
S. mekongi	36 (45.6)	54 (68.4)	65 (82.3)	79 (100)	2 (14.3)	3 (21.4)	8 (57.1)	14 (100)
O. viverrini	74 (83.1)	84 (94.4)	84 (94.4)	89 (100)	2 (18.2)	4 (36.4)	5 (45.4)	11 (100)

Study was carried out among 93 children in primary and secondary schools on Don Long Island, Khong district, Champasack province, Lao PDR in February and March 2007. Sensitivity is compared before (n = 90) and after PZQ administration (n = 66), using the maximum sampling effort as the diagnostic ‘gold’ standard for the following sampling efforts: 1×1 sampling effort examines the first Kato-Katz thick smear only; 1×3 examines the first stool specimen by triplicate Kato-Katz thick smears; 3×1 examines 3 stool specimens by a single Kato-Katz thick smear for each specimen.