Table 5.
Comparison of results of IDT and ES2G

Statistical values	Altogether	Trees	Grasses/Weeds	Indoors
Sensitivity	68.8%	0	25%	73.3%
Specificity	100%	93.8%	92.3%	100%
Positive predictive value	100%	0	50%	100%
Negative predictive value	16.7%	93.8%	80%	33.3%
Observed agreement (OA)	70.6%	88.2%	76.5%	76.5%
Chance agreement (CA)	63%	88.9%	70.2%	61.2%
*Kappa=(OA-CA)/(1-CA)	0.206	–0.06	0.209	0.39
Agreement interpretation	Slight	Poor	Slight	Fair

Kappa coefficient: ≤0=poor, 0.01~0.20=slight, 0.21~0.4=fair, 0.41~0.60=moderate, 0.61~0.80=substantial, and 0.81~1.00=almost perfect agreement.