Table 1

Diagnostic performance of the scent detection dogs stratified by concert

Session	Detection	SARS-CoV-2 infection status		Total no of presented samples	Prevalence	Diagnostic specificity (Sp)	Diagnostic sensitivity (SE)	95% CI Sp	95% CI SE	Diagnostic specificity (regression model)	Diagnostic sensitivity (regression model)	95% CI Sp (regression model)	95% CI SE (regression model)	Rate of concordant results	Positive predictive value (PPV)	Negative predictive value (NPV)
Session	Detection	Positive	Negative	Total no of presented samples	Prevalence	Diagnostic specificity (Sp)	Diagnostic sensitivity (SE)	95% CI Sp	95% CI SE	Diagnostic specificity (regression model)	Diagnostic sensitivity (regression model)	95% CI Sp (regression model)	95% CI SE (regression model)	Rate of concordant results	Positive predictive value (PPV)	Negative predictive value (NPV)
Concert 1	Yes	6	1	475	0.0189	0.9979	0.6667	0.9879 to 0.9999	0.3542 to 0.8794	0.9996	0.7562	0.9988 to 0.9999	0.5144 to 0.9009	0.9916
Concert 1	No	3	465	475	0.0189	0.9979	0.6667	0.9879 to 0.9999	0.3542 to 0.8794	0.9996	0.7562	0.9988 to 0.9999	0.5144 to 0.9009	0.9916
Concert 2	Yes	8	1	650	0.0154	0.9984	0.8	0.9912 to 0.9999	0.4902 to 0.9645	0.9992	0.8510	0.9974 to 0.9998	0.6242 to 0.9515	0.9953
Concert 2	No	2	639	650	0.0154	0.9984	0.8	0.9912 to 0.9999	0.4902 to 0.9645	0.9992	0.8510	0.9974 to 0.9998	0.6242 to 0.9515	0.9953
Concert 3	Yes	9	0	689	0.0159	1	0.8182	0.9944 to 1	0.5230 to 0.9677	0.9995	0.78753	0.9991 to 0.9997	0.6716 to 0.8704	0.9971
Concert 3	No	2	678	689	0.0159	1	0.8182	0.9944 to 1	0.5230 to 0.9677	0.9995	0.78753	0.9991 to 0.9997	0.6716 to 0.8704	0.9971
Concert 4	Yes	8	0	1026	0.0078	1	1	0.9962 to 1	0.6756 to 1	0.9990	0.87763	0.9913 to 0.9999	0.4412 to 0.9849	1
Concert 4	No	0	1018	1026	0.0078	1	1	0.9962 to 1	0.6756 to 1	0.9990	0.87763	0.9913 to 0.9999	0.4412 to 0.9849	1
All concerts	Yes	31	2	2840	0.0134	0.9993	0.8158	0.9974 to 0.9999	0.6658 to 0.9078	0.9993	0.8158	0.9974 to 0.9999	0.6658 to 0.9078	0.9968	0.7002	0.9996
All concerts	No	7	2800	2840	0.0134	0.9993	0.8158	0.9974 to 0.9999	0.6658 to 0.9078	0.9993	0.8158	0.9974 to 0.9999	0.6658 to 0.9078	0.9968	0.7002	0.9996

PPV and NPV were calculated according to Dohoo et al, assuming a prevalence of 0.2%29