Table 2 Characteristics of sample size estimations used in malaria CRTs stratified by outcome measure: prevalence or incidence. There were a total of 65 sample size estimations, 34 based on incidence outcomes while 31 based on prevalence outcomes

Desired power (%)

 80–90

59

90.8

29

85.3

30

96.8

 90–100

6

9.2

5

14.7

1

3.2

Significance level (%)

 10

1

1.5

0

0.0

1

3.2

 5

60

92.3

32

94.1

28

90.3

 2.5

2

3.1

1

2.9

1

3.2

 1.67

2

3.1

1

2.9

1

3.2

Cluster heterogeneity measure

 ICC

10

15.4

6

17.6

4

12.9

 Design effect

3

4.6

2

5.9

1

3.2

 k (CV)

52

80.0

26

76.5

26

83.9

Method used to estimate

Cluster heterogeneity

 With data^a

21

32.3

9

26.5

12

38.7

 Without data

44

67.7

25

73.5

19

61.3

Method used to estimate

Control-arm transmission

 With data^a

38

58.5

24

70.6

14

45.2

 Without data

27

41.5

10

29.4

17

54.8

Retrospectively estimated

Cluster heterogeneity

 Yes

13

20.0

5

14.7

8

25.8

 No

52

80.0

29

85.3

23

74.2

Diagnostic used

 PCR

10

15.4

3

8.8

7

22.6

 RDT

29

44.6

17

50.0

12

38.7

 Microscopy

19

29.2

10

29.4

9

29.0

 Mixed

7

10.8

4

11.8

3

9.7

Age range tested (years)

 < 5

15

23.1

8

23.5

7

22.6

 < 10

14

21.5

9

26.5

8

25.8

 < 15

7

10.8

10

29.4

9

29.0

 All ages

29

44.6

11

32.4

10

32.3