Table 3 The methods used to elicit the margin including the opinion-seeking method, review of evidence base, and guidelines used

Methods used

Opinion seeking without evidence base

7 (17.1)

Evidence based without opinion seeking

11 (26.8)

Opinion seeking and evidence based

17 (41.5)

Neither opinion seeking nor evidence based

6 (14.6)

Used opinion seeking methods

24/41 (58.5)

Opinion seeking stakeholder^ab

Clinicians only

4 (16.7)

Patients only

1 (4.2)

Clinicians and patients

2 (8.3)

Clinicians, patients and researchers

1 (4.2)

Clinicians and researchers

12 (50.0)

Research team

2 (8.3)

Missing

2 (8.3)

Opinion seeking recruitment method^ab

Convenience

12 (50.0)

Relevant mailing lists

4 (16.7)

Convenience and contacting key experts

4 (16.7)

Via a patient and public involvement panel

3 (12.5)

Unclear

1 (4.2)

Opinion seeking method used^ab

Direct questioning

14 (58.3)

Delphi approach

1 (4.2)

Threshold for clinical efficacy

7 (29.2)

Trade-off/elicitation methods

2 (8.3)

Implementation of the opinion seeking method^ab

Survey only

6 (25.0)

Face to face meetings only

10 (42)

Face to face meetings and focus groups or interviews

5 (20.8)

Survey, face to face meeting and focus group

1 (4.2)

Missing

2 (8.3)

Used evidence synthesis methods

28/41 (68.3)

Used systematic review of RCT^b

Yes

9 (32.1)

No

9 (32.1)

Not available at the time of design

8 (28.6)

Missing

2 (7.1)

Evidence used to justify the margin^b

Systematic review or meta-analysis of all relevant RCTs

8 (28.6)

Observational studies or non-RCTs

4 (14.3)

Reviewed multiple RCTs

10 (35.7)

Evidence from one RCT

2 (7.1)

Missing

4 (14.3)

Used guidelines^b

22/41 (53.7)

Guidelines used^b

EMEA 2006

4 (18.2)

FDA 2010

4 (18.2)

ICH E10

1 (4.5)

ICH E9

2 (9.1)

Missing

11 (50.0)