Table 2: Performance of the unadjusted Amsterdam Score.

Parameters shown are for the Amsterdam Score applied to the entire sample (N=757) with missing variables retained. The optimal cut-off using Youden’s index is underlined. +LR, positive likelihood ratio; -LR, negative likelihood ratio.

Cut off	Specificity(%)	Sensitivity(%)	+LR	-LR
≥0	0	100	1	N/A
≥0.9	39.4	98.2	1.62	0.05
≥1.1	48.7	95.5	1.86	0.09
≥1.5	79.9	79.1	3.94	0.26
≥1.6	81.0	78.2	4.11	0.27
≥2	82.8	74.5	4.35	0.31
≥2.4	92.6	65.5	8.82	0.37
≥2.5	93.2	64.5	9.49	0.38
≥2.6	93.8	61.8	10.00	0.41
≥2.7	94.7	60	11.42	0.42
≥2.9	96.6	51.8	15.24	0.50
≥3.1	96.9	51.8	16.76	0.50
≥3.5	97.4	49.1	18.68	0.52
≥3.6	97.7	46.4	20.00	0.55
≥4	98.8	21.8	17.65	0.79
≥4.1	98.8	20.9	16.91	0.80
≥4.2	98.9	20.9	19.33	0.80
≥4.4	99.2	13.6	17.65	0.87
≥4.5	99.4	13.6	22.06	0.87
≥5.1	99.4	10.9	17.65	0.90
≥5.6	99.8	3.6	23.53	0.97
≥5.8	100	3.6	N/A	0.97
≥6	100	2.7	N/A	0.97