Table 1 

Algorithm summary performance statistics for false alarm rates approximating 0.005^{†} 

Algorithm 
false alarm rate 
median (mean) sensitivity 
Day 1 sensitivity 
Day 2 sensitivity 
Days 1–7 sensitivity 
CARL 
median (mean) timeliness^{‡} 
median (mean) adjusted timeliness^{‡} 


EARS C1 
0.0049 
1 (0.53) 
0.13 
0 
0.13 
1.0 
18.5 (54.6) 
34.0 (78.8) 
EARS C2 
0.0042 
1 (0.53) 
0.33 
0 
0.33 
1.0 
0.0 (24.1) 
32.0 (71.1) 
EARS C3 
0.0049 
1 (0.60) 
0.40 
0 
0.40 
1.0 
0.0 (17.9) 
32.0 (68.1) 
NBC 7day 
0.0049 
1 (0.87) 
0.2 
0.07 
0.40 
2.0 
12.0 (16.3) 
14.0 (18.5) 
NBC 14day 
0.0049 
1 (0.93) 
0.2 
0.07 
0.33 
1.6 
9.5 (13.9) 
11.0 (15.2) 
NBC 28day 
0.0049 
1 (1.00) 
0.27 
0.07 
0.60 
2.9 
5.0 (8.5) 
5.0 (8.5) 
NBC 56day 
0.0042 
1 (0.93) 
0.13 
0 
0.27 
3.0 
14.5 (19.1) 
14.0 (18.8) 
pvalue^{¥} 
 
0.0002 
 
 
 
 
0.71 
0.008 


^{†}Test threshold that produced a false alarm rate ≤ 0.005 ^{‡}Detection on the first outbreak day is equivalent to a timeliness of 0 days ^{¥}Friedman rank sum test CARL: Conditional Average Run Length – conditional on the detection of the outbreak during the first 7 days EARS: Early Aberration Reporting System NBC: Negative binomial cusum with an out of control state defined as 2 standard deviations greater than the mean 

Watkins et al. BMC Medical Informatics and Decision Making 2008 8:37 doi:10.1186/14726947837 