Willingness to participate in a randomized trial comparing catheters to fistulas for vascular access in incident hemodialysis patients: an international survey of nephrologists

Krishna Poinen, Matthew J. Oliver, Pietro Ravani, Sabine N. Van der Veer, Kitty J. Jager, Wim Van Biesen, Kevan R. Polkinghorne, Aviva Rosenfeld, Adriane M. Lewin, Mandeep Dulai, Robert R. Quinn

Current guidelines favor fistulas over catheters as vascular access. Yet, the observational literature comparing fistulas to catheters has important limitations and biases that may be difficult to overcome in the absence of randomization. However, it is not clear if physicians would be willing to participate in a clinical trial comparing fistulas to catheters. We also sought to elicit participants' opinions on willingness to participate in a future trial regarding catheters and fistulas. We created a three-part survey consisting of 19 questions. We collected demographic information, respondents' knowledge of the vascular access literature, appropriateness of current guideline recommendations, and their willingness to participate in a future trial. Participants were recruited from Canada, Europe, Australia, and New Zealand. Participants include physicians and trainees who are involved in the care of end-stage renal disease patients requiring vascular access. Descriptive statistics were used to describe baseline characteristics of respondents according to geographic location. We used logistic regression to model willingness to participate in a future trial. We surveyed nephrologists from Canada, Europe, Australia, and New Zealand to assess their willingness to participate in a randomized trial comparing fistulas to catheters in incident hemodialysis patients. Our results show that in Canada, 86 % of respondents were willing to participate in a trial (32 % in all patients; 54 % only in patients at high risk of primary failure). In Europe and Australia/New Zealand, the willingness to participate in a trial that included all patients was lower (28 % in Europe; 25 % in Australia/New Zealand), as was a trial that included patients at high risk of primary failure (38 % in Europe; 39 % in Australia/New Zealand). Nephrologists who have been in practice for a few years, saw a larger volume of patients, or self-identified as experts in vascular access literature were more likely to participate in a trial. Survey distribution was limited to vascular access experts in participating European countries and ultimately led to a discrepancy in numbers of European to non-European respondents overall. Canadian views are likely over-represented in the overall outcomes. Our survey results suggest that nephrologists believe there is equipoise surrounding the optimal vascular access strategy and that a randomized controlled study should be undertaken, but restricted to those individuals with a high risk of primary fistula failure.