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. 2014 Jul 10;14:381. doi: 10.1186/1471-2334-14-381

Table 1.

Performance of different detection algorithms with sensitivity of 100% to detect influenza (UrgIndex-hospitalisation and ICD10-consultations)

Time series
Detection algorithms
Outbreaks periods
Non-epidemic periods
    Mean timeliness (days) Number of days with false alarms N = 1094 Specificity (%)
UrgIndex - hospitalisations
C2, k = 0.08, 1d
−7.5
327
70.1
 
C2, k = 0.08, 3d
−3.3
226
79.3
 
C2, k = 0.1, 1d
−15.3
247
77.4
 
C2, k = 0.1, 3d
5.0
155
85.8
 
C3, k = 0.08, 1d
−58.3
817
25.3
 
C3, k = 0.08, 3d
20.3
739
32.4
 
C3, k = 0.08, 5d
−13.3
589
46.2
 
C3, k = 0.1, 1d
18.3
745
31.9
 
C3, k = 0.1, 3d
−18.3
658
39.9
 
C3, k = 0.1, 5d
−13.3
589
46.2
 
C3, k = 0.5, 1d
0.5
230
79.0
 
C3, k = 1, 1d
5.5
78
92.9
ICD10 – consultations
C1, k = 0.07, 1d
−18.3
151
86.2
 
C1, k = 0.07, 3d
−11.5
127
88.6
 
C1, k = 0.07, 5d
−7.8
115
89.5
 
C1, k = 0.1, 1d
−18.3
148
86.5
 
C1, k = 0.1, 3d
−7.8
122
88.4
 
C2, k = 0.07, 1d
−19.8
147
86.6
 
C2, k = 0.07, 3d
0.5
135
87.7
 
C2, k = 0.07, 5d
2.5
125
88.6
 
C2, k = 0.1, 1d
−13.5
143
86.9
 
C2, k = 0.1, 3d
0.8
131
88.0
 
C2, k = 0.1, 5d
2.8
121
88.9
 
C3, k = 0.07, 1d
−32.3
172
84.3
 
C3, k = 0.1, 1d
−32.3
168
84.6
 
C3, k = 0.1, 3d
−15.8
151
86.2
 
C3, k = 0.1, 5d
−11.3
154
87.0
  C3, k = 0.5, 1d 9.8 74 93.2

C1, C2, and C3 refer to the three different moving average calculations of CUSUM statistics (C1-mild, C2-medium, C3-ultra).

k is the detectable difference to the mean used to the calculation of CUSUM statistics.

Negative mean timeliness: first day signal before the outbreaks beginning, on average.

Positive mean timeliness: first day signal after the outbreaks beginning, on average.