A single‐arm trial indirect comparison investigation: a proof‐of‐concept method to predict venous leg ulcer healing time for a new acellular synthetic matrix matched to standard care control

Abstract

Article:Shannon, R and Nelson, A orcid.org/0000-0001-6741-3078 (2017) A single-arm trial indirect comparison investigation: a proof-of-concept method to predict venous leg ulcer healing time for a new acellular synthetic matrix matched to standard care control. International Wound Journal, 14 (4 ReuseUnless indicated otherwise, fulltext items are protected by copyright with all rights reserved. The copyright exception in section 29 of the Copyright, Designs and Patents Act 1988 allows the making of a single copy solely for the purpose of non-commercial research or private study within the limits of fair dealing. The publisher or other rights-holder may allow further reproduction and re-use of this version -refer to the White Rose Research Online record for this item. Where records identify the publisher as the copyright holder, users can verify any specific terms of use on the publisher's website. TakedownIf you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing eprints@whiterose.ac.uk including the URL of the record and the reason for the withdrawal request. Keywords: wound healing; non-healing leg ulcer; acellular synthetic matrix; predictive analytics; propensity score; venous ulcers; evidence network; VenUS I study, VenUS II study, VenUS III study, VenUS IV study 2 Abstract:PURPOSE: To compare data on time to healing from two separate cohorts: one treated with a new acellular synthetic matrix plus standard care and one matched from four large UK pragmatic, randomized controlled trials (venous leg ulcer evidence network). We introduce a new proof of concept strategy to a venous leg ulcer clinical evidence network, propensity score matching and sensitivity analysis to predict the feasibility of the new acellular synthetic matrix plus standard care for success in future randomized, controlled clinical trials. SUBJECTS AND METHODS:Prospective data on chronic, venous leg ulcers from a safety and effectiveness study on an acellular synthetic matrix conducted in one wound center in the UK (17 patients) and three wound centers in Australia (36 patients) were compared retrospectively to propensity score matched data from patients with comparable leg ulcer disease etiology, age, baseline ulcer area, ulcer duration, multilayer compression bandaging and majority of care completed in specialist wound centers (avg. 1 visit per week) with the outcome measures at comparable follow-up periods, from patients enrolled in four prospective, multicenter, pragmatic, randomized studies of venous ulcers in the United Kingdom (the comparison group; venous leg ulcer evidence network). RESULTS: CONCLUSIONS:Results from this study predict a significant effect on healing time when using a new ASM as an adjunct to standard care in the treatment of non-healing venous ulcers in the UK, but results are sensitive to unobserved covariates that may be important in healing time comparison.

A cost-effectiveness analysis of a hydration response technology dressing in the treatment of venous leg ulcers in the UK

“…Transition probabilities for moving patients from unhealed grade 1 progression (HS 2) to healed were based on Panca et al [17]. [20] and assumed to be independent to the underlying treatment. The transition probability for unhealed grade 1 static to unhealed grade 1 deteriorating (HS 3 to HS 4) was based on Walzer et al…”

Health Economics and Outcomes Research of Wound Care: Overview of Methodology

“…For example, PSM was used to compare clostridial collagenase ointment to medicinal honey as an adjunct therapy to selective sharp debridement in patients with stage III/IV pressure ulcers, and to compare patients treated with acellular synthetic matrix plus standard care to standard care for patients with venous leg ulcers. [11][12][13] IPTW uses weights based on the propensity score to create a synthetic sample in which the distribution of measured baseline covariates is independent of treatment. 14 Each individual in the cohort is assigned a weight based on the probability that they would be exposed to the treatment.…”