Table 4.

Agreement statistics estimation (kappa coefficient and Bowker symmetry test) comparing species-specific DNA amplification by PCR and LAMP for both Qiagen- and LAMP-PURE–extracted DNA for Schistosoma mansoni

Comparison of diagnostic tests	Kappa coefficient		Bowker’s symmetry test*
	Degree of agreement	95% CI	Symmetry of disagreement	P-value†
PCR-Qiagen vs. LAMP-Qiagen	0.38	0.17–0.58	18	0.0001‡
PCR-Qiagen vs. PCR_LAMP-PURE	−0.08	−0.25–0.09	0	1.0000
PCR-Qiagen vs. LAMP_LAMP-PURE	0.30	0.08–0.51	5.26	0.0218‡
LAMP-Qiagen vs. LAMP_LAMP-PURE	0.01	−0.17–0.19	2.58	0.1083

LAMP-PURE = loop-mediated isothermal amplification-Procedure for Ultra Rapid Extraction; PCR = polymerase chain reaction.

* Bowker’s symmetry test = this test checks for symmetry in two-way tables and the test decision is based on a χ² approximation of the distribution of the test statistic.

† α level was set at 0.05.

‡ Significant. P-values are highlighted in bold.