Table 1.
Summary characteristics of COS discussed in interviews
| Characteristics | Published N = 18; number of COS (% of 18) | Ongoing N = 14; number of COS (% of 14) | Total N = 32; number of COS (% of 32) |
|---|---|---|---|
| Methods used (not mutually exclusive) | |||
| Systematic/literature review | 7 (39) | 8 (57) | 15 (47) |
| Delphi | 7 (39) | 10 (71) | 17 (53) |
| Semistructured group discussiona | 10 (55) | 6 (43) | 16 (50) |
| Consensus development conference | 2 (11) | 0 (0) | 2 (6) |
| Nominal group technique | 1 (5) | 0 (0) | 1 (3) |
| Focus groups | 0 (0) | 3 (21) | 3 (9) |
| Survey | 2 (11) | 2 (14) | 4 (12) |
| Unstructured group discussionb | 1 (5) | 0 (0) | 1 (3) |
| Interviews | 0 (0) | 5 (36) | 5 (16) |
| Methods not described | 1 (5) | 2 (14)c | 3 (9) |
| Groups participating in COS development | |||
| Clinical experts | 16 (89) | 14 (100) | 30 (94) |
| Patients | 8 (44) | 12 (86) | 20 (62) |
| Research methods experts | 8 (44) | 7 (50) | 15 (47) |
| Representatives from regulatory authorities (e.g., FDA) | 6 (33) | 2 (14) | 8 (25) |
| Representatives from industry (e.g., pharmaceutical companies) | 5 (28) | 1 (7) | 6 (19) |
| Other (e.g., journal editors) | 1 (5) | 1 (7) | 2 (6) |
| Not described | 1 (5) | 0 (0) | 1 (3) |
| International participants | |||
| Yes (participants from two or more countries) | 11 (61) | 9 (64) | 20 (62) |
| No (participants from one country) | 7 (39) | 5 (36) | 12 (37) |
| Study aims | |||
| Outcomes only | 11 (61) | 12 (86) | 23 (72) |
| Wider trial design issues | 7 (39) | 2 (14)d | 9 (28) |
| How to measure | |||
| What to measure only | 8 (44) | 12 (86) | 20 (62) |
| What to measure + discussion/consideration of how but no recommendation | 4 (22) | n/a | 4 (12) |
| What + how (done together) | 5 (28) | 1 (7) | 6 (19) |
| What + how (done in two stages) | 1 (5) | 1 (7) | 2 (6) |
| Whether COS intended for adults or children | |||
| Both | 1 (5) | 1 (7) | 2 (6) |
| Children | 4 (22) | 3 (21) | 7 (22) |
| Adults | 3 (17) | 10 (71) | 13 (41) |
| Not specified | 10 (55) | 0 (0) | 10 (31) |
| Type of intervention COS intended for | |||
| All | 3 (17) | 8 (57) | 11 (34) |
| Drug | 4 (22) | 0 (0) | 4 (12) |
| Surgery | 0 (0) | 5 (36) | 5 (16) |
| Specific (other) | 3 (17) | 1 (7) | 4 (12) |
| Not specified | 8 (44) | 0 (0) | 8 (25) |
| Number of existing COS/disease category | |||
| Clinical area where more than 5 | 14 (78) | 11 (79) | 25 (78) |
| Clinical area where less than 5 | 4 (22) | 3 (21) | 7 (22) |
| Funding | |||
| Commercial (e.g., drug company) | 3 (17) | 0 (0) | 3 (9) |
| Noncommercial | 7 (39) | 13 (93) | 20 (62) |
| Commercial and noncommercial | 3 (17) | 0 (0) | 3 (9) |
| No funding | 1 (5) | 1 (7) | 2 (6) |
| Not reported | 4 (22) | 0 (0) | 4 (12) |
Abbreviation: COS, core outcome set.
a
Descriptions included workshop, meeting, and roundtable.
b
Descriptions included task force, work group, working group/party, committee, board, and panel.
c
Consensus methods, in addition to systematic review, were not known before the interview.
d
Part of a wider PhD.