Indicators of outcome quality in peripheral arterial disease revascularisations - a Delphi expert consensus

Introduction: Peripheral arterial disease (PAD) affects a continuously increasing number of people worldwide leading to more invasive treatments. Indication to perform invasive revascularisations usually arises from consensus-based recommendations of practice guidelines and from few randomized controlled trials where outcome measures focus mainly on risk factors associated with mortality and morbidity. To date, no broad consensual agreement of experts on valid indicators of outcome quality exists for PAD. Methods: A literature review was conducted to collect indicators of outcome quality from studies of PAD. The Delphi technique was used to achieve a consensual agreement on a set of core indicators. The expert panel of the two-round Delphi approach was formed by leading vascular specialists joining the IDOMENEO study, physician assistants, wound nurses, and patient representatives. Items were scored via a web-based anonymised electronic questionnaire using a five-point Likert-scale. Results: Out of 40 invited experts 30 joined the panel and completed round one. Twenty-four experts completed the second and final round. Forty-three indicators of outcome quality were initially identified and validated by the panel. After two Delphi rounds, 12 indicators (27.9 %) achieved the limit of agreement for relevance and four (9.3 %) for practicability. Major adverse limb events (MALE), major amputation, and major re-intervention (or re-operation) were consented as both highly relevant and practicable. Additionally, major adverse cardiovascular events (MACE), myocardial infarction, stroke or transient ischaemic attack, all-cause death, all re-intervention (or re-operation), wound infection, vascular access-related major complication, walking distance, and Rutherford-classification were consented as highly relevant. Ankle-brachial-index was consented as highly practicable. Conclusions: This Delphi approach of vascular experts identified three indicators as highly relevant and clinically practicable to be recommended as indicators of outcome quality in invasive PAD treatment. Among others, these consented items may help in harmonising future studies and quality benchmarking increasing their comparability, validity, and efficiency.