Table 1 Key characteristics of RDS recruitment methodology in the Rural Opioid Initiative by study

Personal network size used as a seed selection criterion

1/7

No

Yes^a

No

No

No

No

No

Total number of seeds

562

53

48

50

51

45

42

273

 Non-generative seeds

251 (45%)

38 (72%)

24 (50%)

13 (26%)

13 (25%)

23 (51%)

18 (43%)

122 (45%)

 Seeds with ≥5 waves

46 (8%)

1 (2%)

4 (8%)

6 (12%)

11 (22%)

3 (7%)

4 (10%)

17 (6%)

 Wave size range, median (range)

1 (0-14)

0 (0-5)

0.5 (0-13)

1 (0-11)

1 (0-14)

0 (0-13)

1 (0-7)

1 (0-11)

Coupons per recruiter^b

3-7

6

3

3-4

3-7

4-5

3-4

3-5

Incentive for participation^c

$20-40

$40 for completing the survey

$45 for completing the survey and rapid testing

$40 for completing the survey

$20 for completing the survey and rapid testing

$25 for completing the survey

$25 for completing the survey

$20 for completing the survey and rapid testing

Incentive for recruitment

$10-20

$20 per eligible referral

$10 per eligible referral who enrolled

$20 per eligible referral who enrolled

$10 per eligible referral who completed all study activities

$10 per eligible referral

$10 per eligible referral

$10 per eligible referral who enrolled

Duplicate participants identified

20

2

3

0

0

3

1

14

 Downstream recruits of duplicates

31

7

0

0

0

6

0

18