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Table 4 Bias of SCR estimates before and after a change in transmission under the assumption of a unknown change point

From: Sample size and power calculations for detecting changes in malaria transmission using antibody seroconversion rate

   

True time point for change in transmission

3 yearsb

5 yearsb

10 yearsb

SCR beforea

SCR aftera

Sample size

SCR before

SCR after

SCR before

SCR after

SCR before

SCR after

0.0969

0.0324

250

368.2

−11.4

549

−23.2

1835.9

−7.1

  

500

34.2

−22.1

47.4

−21.9

998.1

−2.4

  

1000

11.2

−8.2

9.1

−10.7

143.1

−2.4

  

2500

2.5

−5.1

4.4

−3.0

8.4

−1.6

0.0969

0.0108

250

215.5

−9.3

113.8

−17.6

671.3

−10.0

  

500

18.0

−8.2

23.8

−17.0

96.6

−4.1

  

1000

5.9

1.3

5.2

−3.4

27.3

−2.0

  

2500

2.0

4.7

2.1

−2.6

3.2

−1.4

0.0324

0.0108

250

325.3

−14.0

191.9

−26.7

5384.0

−11.2

  

500

66.0

−21.5

25.4

−32.8

1227.1

−7.8

  

1000

13.2

−24.6

13.2

−25.2

126.7

−5.0

  

2500

5.2

−16.6

6.4

−9.5

12.9

−2.8

0.0324

0.0108

250

534.7

20.9

105.9

−29.9

2254.6

−10.2

  

500

59.8

0.6

31.0

−25.2

237.8

−9.4

  

1000

12.6

−8.2

10.6

−11.3

20.8

−7.4

  

2500

4.7

−0.4

4.5

−2.4

4.7

−3.2

  1. aExpected number of events per year
  2. bYears before sampling