The Core Outcome Set Taskforce for CF (COST-CF)

The project will develop core outcome sets for clinical studies in cystic fibrosis (CF). CF is a multisystem disease. The COST-CF project will act as an “umbrella registration” with several core outcome sets sitting beneath the umbrella. At present, we envisage that these will include core outcome sets for: pulmonary exacerbations; gastrointestinal problems; and CF related diabetes. This list may expand to address other important clinical trial areas in CF.

Many clinical trials in CF have small numbers of participants and so are underpowered (J Cyst Fibros. 2006;5:13-8). A systematic review of evidence gaps in CF (Thorax. 2019;74:3229-36) found only 30 “known, knowns” vs 148 evidence gaps. One explanation for this large number of evidence gaps is the lack of a COS in CF, which would allow small trials to be combined in meaningful systematic reviews, to guide practice.


Principal Investigator - Prof Alan Smyth

Further Study Information

Current Stage: Ongoing
Date: January 2017 - December 2025
Funding source(s): Currently seeking funding from the UK National Institute for Health Research (NIHR) and other funders

Health Area

Disease Category: Genetic disorders

Disease Name: Cystic fibrosis

Target Population

Age Range: 0 - 100

Sex: Either

Nature of Intervention: Drug, Physiotherapy, Diet and nutrition, Exercise, Other, Psychological & behavioural

Stakeholders Involved

- Charities
- Clinical experts
- Consumers (caregivers)
- Consumers (patients)
- Economists
- Methodologists
- Patient/ support group representatives
- Pharmaceutical industry representatives
- Regulatory agency representatives
- Statisticians

Study Type

- COS for clinical trials or clinical research
- COS for practice


- Consensus meeting
- Delphi process
- Focus group(s)
- Interview
- Other
- Systematic review

Other: We have conducted a James Lind Alliance Priority Setting Partnership exercise (online questionnaire) which has elicited information from people with CF, their family members and from health professionals about research priorities and also outcome measures.

Stage 1. Systematic review to report the range of clinical outcomes and endpoints and (where possible) their validity, reliability and sensitivity to change.
Stage 2. Workshops and online surveys to elicit suggested outcome measures and endpoints from people with CF and the parents of children with CF.
Stage 3. A series of online Delphi surveys to determine which COS domains from stage 1 and stage 2 are most important to stakeholders.
Stage 4. A final workshop (conducted virtually) to agree the COS.
Stage 5. Publication and dissemination.