Standardised outcomes in nephrology-haemodialysis (song-hd): Using the delphi method to gain consensus on core outcomes for haemodialysis trials

Despite the growing number of trials in haemodialysis, substantial improvements in mortality and quality of life outcomes remains to be seen (Inrig et al., 2014; Nissenson, 2014). This may be partly explained by problems with the way outcomes are currently measured and reported. The overwhelming heterogeneity of outcomes makes it difficult to compare results across trials (Williamson et al., 2012). Patients have little involvement in the selection of outcomes and thus the omission of patient relevant outcomes can undermine shared‐decision making (Chalmers et al., 2014; Gargon et al., 2014; Ghandi, 2008). Also, outcome selection bias can result in patient harm as adverse events may not be reported. These problems have driven an urgent need to identify standardised outcomes for research that are relevant and important to stakeholders.