Table 2 Study duration, number of study visits, percentage of male participants of the study, and details of recruitment and retention numbers (n.d indicates that no data was available in the published literature)

Amin et al. 2023 [38]

3 years

F

9^a

50%

n = 93; parent study

n = 75; Questionnaire

n = 19; Interview

80.1% Questionnaire

16.1% Interview

Cheraghi et al. 2021 [39]

20 years

Ret & F

5

42.39%

n = 4,395

n.d^#

55% > 60 years

67% 40–59 years

57% 20–39 years

Crichton et al. 2012 [57]

1 year

Rec, Ret & F

3

27%

n = 20; 18–71 years

n = 10

50%

Goldberg et al. 2006 [42]

11 years

F

11

73%

n = 8,550; 40–45 years

n = 6,277; 45–50 years

n.d^*

n.d

Gourash et al. 2022 [48]

5 years

Rec, Ret & F

6

21.4%

n = 527

n.d^*

n.d^*

Green et al. 2018 [40]

Study launched in 2010^b

Rec

3^c

43.7%

n = 3,315

n = 1,172

35.4%^#

Griffith Fillipo et al. 2022 [49]

13 weeks

Ret & F

3

14%

n = 19; low incentive

n = 11; high incentive

n = 30

100%

Hamberger et al. 2000 [50]

Recruitment duration: 6 years 2 months, Study duration: 16 weeks

Rec, Ret & F

16

100%

n = 534

n = 150; 25–34 years

n = 49; < 25 years

n = 76; ≥ 35 years

28% 25–34 years

9.2% < 25 years

14.2% 35 years

Irvine et al. 2017 [41]

5 months

Rec, Ret & F

96

100%

n = 69

n = 59

85.5%

Janus et al. 1997  [51]

4 years

Ret

4

50%

n = 209

n = 135

64.6%

Kannisto et al. 2017 [44]

1 year

Rec, Ret & F

24-300^d

49.17%

n = 560

n = 227

41.0%^e

Kelfve et al. 2017 [45]

43 years

F

7

15.2%

n = 172

n = 134^f

41.4% 77–87 years

Lee et al. 2009 [61]

6 years

Rec

3

100%

n = 3,963

n = 3,369

38.7% 40–49 years

45.0% 50–59 years

43.2% 60–69 years

34.4% > 70 years

Limmroth et al. 2023 [47]

1 year

Rec, Ret & F

5

34%

n = 21

n = 21

100%

Markanday et al. 2013 [58]

10 years

Rec

3^g

50.8%

n = 2,296

n = 1,540

67.1%

Méjean et al. 2014 [43]

10 years

Rec & Ret

11-120^h

24.1%

n = 3,929

n = 1,531

24.1%

Oleske et al. 2007 [52]

1 year

F

5

79.3%

n = 360

n = 168

83.6% 47.1 ± 6.7 years

Olmos-Ochoa et al. 2019 [53]

6 months

Rec, Ret & F

24 or 30ⁱ

Overall Study: 93.9%

Sub Study: 83.3%

n = 260

n = 40

n.d^j

n.d^*

Pogue et al. 2022 [54]

2 years

Rec, Ret, F

6

25.5%

n = 324

n.d^k

n.d^k

Rose et al. 1976 [36]

12 years

Rec & Ret

n.d^l

100%

n = 2,280

n = 2,028

88.9%

Schilling et al. 2023 [37]

1 year

Rec & Ret

12

74.02%

n = 4,371

n.d^*

n.d

Snow et al. 2007 [55]

11 years

Ret & F

6

62.4%

n = 3,327

n = 2,749

82.6%

Ullman et al. 1998 [56]

16 years

Rec & Ret

4

37.6%

n = 207

n = 201

97.1%

vanWees et al. 2019 [46]

2 years

F

4

19%

n = 324

n = 206

63.6%