Table 1

Participation and positivity rates in the first screening round and minimal detectable difference in positivity between rounds 1 and 2 at a power of 80%.

Number invited

Participation rate % (95% CI)

Positivity rate % (95% CI)

Detectable decline of positivity rate (in % after screening)


Amsterdam

Block A

25,121

18.0 (17.5-18.5)

2.9 (2.5-3.5)

Block A versus block B

0.9

Block B

114,937

16.8 (16.6-17.0)

3.7 (3.5-4.0)

Block A versus block C

1.2

Overall

140,058

17.0 (16.8-17.2)

3.4 (3.8-0.2)

Round 1 to round 2

0.5


Rotterdam

Block A

17,929

14.8 (14.2- 15.3)

6.2 (5.3-7.2)

Block A versus block B

1.4

Block B

89,877

15.3 (15.0-15.5)

4.9 (4.5- 5.2)

Block A versus block C

1.8

Overall

107,806

15.2 (15.0-15.4)

5.1 (4.7-5.4)

Round 1 to round 2

0.8


South Limburg*

Block A

13,124

11.0 (10.5-11.5)

5.1 (4.1-6.4)

Block A versus block B

1.9

Overall (only block A in first round)

Round 1 to round 2

1.2


* with application of a selection based on risk scores

van den Broek et al. BMC Infectious Diseases 2010 10:89   doi:10.1186/1471-2334-10-89

Open Data