Pilot testing has shown that a new framework—dubbed Endo-STAR—can be used to describe and standardise endovascular interventions for peripheral arterial disease (PAD) within a randomised controlled trial (RCT) protocol and monitor adherence to the protocol over the course of a trial. Ewa M Zywicka (University of Bristol Medical School, Bristol, UK) shared this conclusion during the Prize Session at the recent European Society for Vascular Surgery (ESVS) annual meeting (24–27 September, Kraków, Poland).
Zywicka began by noting that rigorous evaluation of novel lower-limb endovascular interventions is “critically important” to ensure adoption of effective technologies and rejection of those that are ineffective or harmful.
The presenter continued that poor reporting of RCTs limits the evaluation of technologies for lower-limb endovascular interventions, highlighting a recent study in which more than half of RCTs did not adequately describe interventions, and almost 80% did not report any form of standardisation.
The aim of Zywicka and colleagues’ present study, therefore, was to develop a specific framework for describing and standardising endovascular lower-limb interventions within clinical trials.
Zywicka explained to the ESVS audience that the Endo-STAR framework was developed using qualitative research methodology and the Enhancing the Quality and Transparency of Health Research (EQUATOR) methodological framework. The presenter added that trial reports and associated protocols identified in a recent systematic review of endovascular infrainguinal lower-limb RCTs for PAD provided the data for developing the preliminary framework.
Going into more detail about the research methods used, Zywicka detailed that a framework approach to thematic analysis of qualitative data was employed to code and categorise text into steps and components of endovascular infrainguinal interventions.
Subsequently, focus groups were conducted with key international stakeholders such as clinical practitioners—namely vascular surgeons, interventional radiologists, angiologists and cardiologists—trialists, industry representatives and journal editors to refine the framework and consider clarity and feasibility issues. Zywicka noted that the framework was updated based on this feedback, and a consensus between stakeholders was reached via a modified Delphi-style questionnaire.
Finally, Zywicka shared, the framework was refined through cognitive interviews with trialists to test the real-world feasibility of using the Endo-STAR framework in contemporary endovascular RCTs. An online version of the Endo-STAR framework was developed to facilitate implementation and dissemination.
At ESVS, Zywicka informed attendees that the preliminary framework was developed after including data from 112 RCTs evaluating endovascular infrainguinal interventions for PAD.
Zywicka relayed that 24 key stakeholders participated in three focus groups, contributing to the refinement of the framework, and all 24 participants took part in the consensus questionnaire. After the first round of the questionnaire, the presenter continued, an agreement above 85% was reached for each framework section. Ten trialists involved in contemporary endovascular trials took part in pilottesting the framework.
Ultimately, Zywicka reported, the Endo-STAR framework was structured into six main sections: 1) expertise of the professional delivering the intervention, 2) setting/location of the intervention, 3) anaesthesia provided for the intervention, 4) imaging used at the time of the intervention, 5) intervention components: access, crossing the lesion, treating the lesion (including specific steps and details related to all currently available endovascular devices) and closure of the artery, and 6) pharmacological interventions.
In discussion time following Zywicka’s talk, jury member Jon Boyle (Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK) asked how the framework might help in terms of monitoring long-term outcomes of endovascular interventions, to which the presenter responded: “What we are aiming to achieve with this framework is to know what has been done in a trial […] we expect that actually being able to know and clearly describe what was done in a trial can be used to easily compare trials and even potentially compare results in the long term as well.”
