Search strategy and evidence selection

Search strategy and evidence selection

Search strategy

A search was conducted to identify evidence on the clinical and cost effectiveness of the Gore PROPATEN heparin‑bonded vascular graft.

The strategy was developed in MEDLINE (Ovid). The strategy was devised using a combination of subject indexing terms and free text search terms that described the indication and free text search terms that specifically described the device. No limits were applied to the search.

The strategy was adapted for the following databases: Medline in Process, Embase, Cochrane Library (CENTRAL, CDSR, DARE, HTA, NHS EED), EconLit, Pubmed ('epub ahead of press' search only of key terms), Scopus and Web of Science (Web of Science – Science Citation Index and Conference Proceedings Citation Index‑ Science). Citation tracking in Google Scholar of included studies was also performed. The searches returned a total of 98 references after duplicate removal.

Information supplied by the manufacturer and also the manufacturer's website were checked for relevant studies.

ClinicalTrials.gov and the International Clinical Trials Registry Platform (ICTRP) were searched to identify ongoing or in‑development trials.

Evidence selection

Retrieved results were independently sifted by two researchers using the selection criteria below, and disagreements discussed and resolved.

  • Population: patients with symptomatic peripheral arterial disease in whom a peripheral vascular bypass procedure using a prosthetic graft is clinically indicated

  • Intervention: PROPATEN heparin‑bonded vascular graft (Gore)

  • Comparators: Autologous lower extremity bypass, standard (non‑heparin bonded) prosthetic graft, and other types of heparin‑bonded prosthetic graft

  • Outcomes:

    • procedural complications

    • primary patency rate

    • secondary patency rate

    • amputation rates

    • graft failure

    • graft occlusion

    • infection

    • re‑intervention rates

    • limb salvage rate

    • death

    • heparin‑induced thrombocytopaenia (HIT)

    • perioperative or postoperative bleeding.

Following the first sift, 59 records were removed based on the following criteria:

  • not relevant to selection criteria

  • review articles and conference abstracts.

Full articles were requested for the remaining 36 studies, one of which was not available. Additional studies were provided by the manufacturer.

Due to the abundance of data, it was necessary to further refine the remit. The following criteria were applied:

  • Study design. Due to the large number of relevant studies, only randomised controlled trials and comparative studies were considered for inclusion.

  • Comparator. Of the comparative studies, all those comparing PROPATEN to other types of prosthetic grafts were included. Of those comparing PROPATEN to ASV, multisite studies and studies with more than 200 patients were included.

  • Multiple comparators. One further study was identified by the manufacturer. This was the only 3‑arm study identified (comparing PROPATEN with standard ePTFE graft and ASV).

Ultimately six studies were selected for inclusion in this briefing.