Preferred health outcome states following treatment for pulmonary exacerbations of cystic fibrosis.

BACKGROUND: Treatment for pulmonary exacerbations of cystic fibrosis (CF) can produce a range of positive and negative outcomes. Understanding which of these outcomes are achievable and desirable to people affected by disease is critical to agreeing to goals of therapy and determining endpoints for trials. The relative importance of outcomes resulting from treatment of these episodes are not reported. We aimed to (i) quantify the relative importance of outcomes resulting from treatment for pulmonary exacerbations and (ii) develop patient and proxy carer-reported weighted outcome measures for use in adults and children, respectively. METHODS: A discrete choice experiment (DCE) survey was conducted. Participants were asked to make a series of hypothetical decisions about treatment for pulmonary exacerbations to assess how they make trade-offs between different attributes of health. Data were analysed using a conditional logistic regression model. The correlation coefficients from these data were rescaled to enable generation of a composite health outcome score between 0 and 100 (worst to best health state). RESULTS: 362 individuals participated (167 people with CF and 195 carers); of these, 206 completed the survey (56.9%). Most participants were female and resided in Australia. Difficult/painful breathing had the greatest impact on the preferred health state amongst people with CF and carers alike. Avoidance of gastrointestinal problems also heavily influenced decision-making. CONCLUSIONS: These data should be considered when making treatment decisions and determining endpoints for trials. Further research is recommended to quantify the preferences of children and to determine whether these align with those of their carer(s).

Novel method to select meaningful outcomes for evaluation in clinical trials.

BACKGROUND: A standardised framework for selecting outcomes for evaluation in trials has been proposed by the Core Outcome Measures in Effectiveness Trials working group. However, this method does not specify how to ensure that the outcomes that are selected are causally related to the disease and the health intervention being studied. Causal network diagrams may help researchers identify outcomes that are both clinically meaningful and likely to be causally dependent on the intervention, and endpoints that are, in turn, causally dependent on those outcomes. We aimed to (1) develop a generalisable method for selecting outcomes and endpoints in trials and (2) apply this method to select outcomes for evaluation in a trial investigating treatment strategies for pulmonary exacerbations of cystic fibrosis (CF). METHODS: We conducted a series of online surveys and workshops among people affected by CF. We used a modified Delphi approach to develop a consensus list of important outcomes. A workshop involving domain experts elicited how these outcomes were causally related to the underlying pathophysiological processes. Meaningful outcomes were prioritised based on the extent to which each outcome captured separate rather than common aspects of the underlying pathophysiological process. RESULTS: The 10 prioritised outcomes were: breathing difficulty/pain, sputum production/clearance, fatigue, appetite, pain (not related to breathing), motivation/demoralisation, fevers/night sweats, treatment burden, inability to meet personal goals and avoidance of gastrointestinal symptoms. CONCLUSIONS: This proposed method for selecting meaningful outcomes for evaluation in clinical trials may improve the value of research as a basis for clinical decisions.