Table 4 Associations between the top five most successful recruitment strategies and the sociodemographic variables age, sex (female) and educational attainment (high education) (n = 391)

Recruited via mailing of recruitment flyers and letters (n =  288)

− 1.76

(− 4.29; 0.70)

1.00

(0.60; 1.64)

1.22

(0.76; 1.98)

Recruited via flyers in the supermarket (n = 52)

2.56

(− 0.63; 5.85)

1.91

(0.93; 4.31)

0.72

(0.38; 1.33)

Recruited via media news article (n = 31)

2.33

(− 1.69; 6.44)

1.64

(0.69; 4.51)

0.67

(0.29; 1.45)

Recruited via in-store recruitment (n = 30)

− 0.11

(− 4.19; 4.06)

1.21

(0.52; 3.14)

1.75

(0.81; 3.81)

Recruited via word-of-mouth (n = 24)

− 0.40

(− 4.94; 4.14)

0.51

(0.22; 1.21)

1.01

(0.42; 2.35)