Applying cusum-based methods for the detection of outbreaks of Ross River virus disease in Western Australia

Table 3 Descriptive statistics for summary performance characteristics for the EARS and NBC algorithms: receiver operating characteristic area under the curve (AUC) analyses

Algorithm	median (mean) AUC_0–1	median (mean) AUC_0–0.01 ^†	median (mean) AUC_0–0.005 ^‡	median (mean) WtAUC_0–1	median (mean) WtAUC_0–0.01 ^‡
EARS C1	0.995 (0.989)	0.0011 (0.0019)	0.0004 (0.0015)	0.959 (0.968)	<0.0001 (0.0008)
EARS C2	0.996 (0.990)	0.0017 (0.0026)	0.0002 (0.0016)	0.994 (0.978)	0.0002 (0.0013)
EARS C3	0.996 (0.993)	0.0061 (0.0059)	0.0011 (0.0022)	0.991 (0.980)	0.0011 (0.0033)
NBC 7-day	1.0 (0.998)	0.0095 (0.0081)	0.0049 (0.0040)	0.990 (0.979)	<0.0001 (0.0032)
NBC 14-day	1.0 (0.999)	0.0099 (0.0088)	0.0049 (0.0040)	0.988 (0.981)	<0.0001 (0.0026)
NBC 28-day	1.0 (1.0)	0.0095 (0.0092)	0.0049 (0.0047)	0.990 (0.983)	0.0014 (0.0032)
NBC 56-day	1.0 (0.999)	0.0095 (0.0088)	0.0042 (0.0036)	0.977 (0.928)	<0.0001 (0.0018)
p-value^¥	<0.0001	<0.0001	<0.0001	0.046	0.006

^†Evaluated at a false alarm rate ≤ 0.01
^‡Evaluated at a false alarm rate ≤ 0.005
^¥Friedman rank sum test
WtAUC: Weighted AUC using a reference value of 7 days for valid detection
EARS: Early Aberration Reporting System
NBC: Negative binomial cusum with an out of control state defined as 2 standard deviations greater than the mean

ISSN: 1472-6947