Table 2.

Apparent diagnostic performance characteristics of a perfect biomarker as a function of disease prevalence and sensitivity and specificity of an imperfect gold standard

Imperfect Gold Standard Diagnostic Performance	True Disease Prevalence, %	Apparent Sensitivity, %	Apparent Specificity, %	Lower Bound of AUC-ROC	Upper Bound of AUC-ROC	AUC-ROC Assuming Conditional Independence
80% sensitive, 90% specific	5	30	99	0.29	0.99	0.64
	10	47	98	0.46	0.99	0.72
	20	67	95	0.63	0.98	0.81
	40	84	87	0.73	0.98	0.86
	60	92	75	0.69	0.98	0.84
80% sensitive, 80% specific	5	17	99	0.17	0.99	0.58
	10	31	97	0.30	0.98	0.64
	20	50	94	0.47	0.97	0.72
	40	73	86	0.62	0.96	0.79
	60	86	73	0.64	0.96	0.79
25% sensitive, 100% specific	5	100	96	0.96	1.00	0.98
	10	100	92	0.92	1.00	0.96
	20	100	84	0.84	1.00	0.92
	40	100	67	0.67	1.00	0.83
	60	100	47	0.47	1.00	0.74
25% sensitive, 99% specific	5	57	96	0.55	0.98	0.76
	10	74	92	0.68	0.98	0.83
	20	86	84	0.72	0.98	0.85
	40	94	66	0.63	0.98	0.80
	60	97	47	0.46	0.99	0.72
100% sensitive, 25% specific	5	7	100	0.07	1.00	0.53
	10	13	100	0.13	1.00	0.56
	20	25	100	0.25	1.00	0.63
	40	47	100	0.47	1.00	0.74
	60	67	100	0.67	1.00	0.83