Table 2 Design and context of included studies

Study design

 Cluster RCT

43

53.8%

 Individual RCT

37

46.3%

Country

 North America

51

63.8%

 Europe

23

28.8%

 Rest of the world^a

6

7.5%

Setting

 Primary care

72

90.0%

 Secondary care inpatient

7

8.8%

 Other^b

1

0.01%

Health condition/disease of interest

 Cardiovascular disease

12

15.0%

 General health

11

13.8%

 Cancer

11

13.8%

 Vaccinations

9

11.3%

 Mental health

7

8.8%

 Diabetes

5

6.3%

 Respiratory disease

3

3.8%

 Other^c

22

27.5%