Table 5

Pooled participation levels and corresponding 95% confidence intervals for study characteristics

study characteristics

number of studies (n)*

number of participants (n)

mean (%) [95% CI]

incentive

9

11960

33.5%

[33.3% – 33.8%]

no incentive

13

18060

30.7%

[30.5% – 30.9%]

fee

4

4053

32.2%

[31.8% – 32.7%]

no fee

18

26740

31.7%

[31.5% – 31.9%]

education/counselling

10

15022

28.0%

[27.8% – 28.2%]

fitness

6

3914

25.8%

[25.4% – 26.1%]

multi-component

6

11084

43.3%

[42.9% – 43.3%]

physical activity

10

6474

29.2%

[28.9% – 29.5%]

multiple behaviours

12

23546

32.6%

[32.4% – 32.8%]

Robroek et al. International Journal of Behavioral Nutrition and Physical Activity 2009 6:26   doi:10.1186/1479-5868-6-26