Table 3 Trialists’ understanding of core outcome sets (COS)

COS are the minimum that should be measured for specific health or health care area

4

1–5

4

COS are the minimum that should be reported for specific health or health care area

4

1–5

4

All outcomes in the COS should be measured

4

1–5

2

Other outcomes can be measured in addition to outcomes in COS

5

2–5

1

COS can be used in research other than trials (e.g. evidence synthesis, observational studies)

5

3–5

1

COS are relevant to clinical audit and routine care

4

3–5

1

COS can involve input from relevant stakeholders

5

3–5

1

COS require consensus processes in development

5

2–5

1

Development of a COS involves multiple stages

5

4–5

0.75

Understanding of what COS are

4

2–5

1

Perceived importance of COS in clinical trials

3

2–3

1