Study	Reason for exclusion
Bennion 1985	Results presented include non‐randomised patients. Randomisation technique unclear. Distal grafts included, not intention to treat
Chikiar 2003	Retrospective, non‐randomised study (not an RCT or CCT): retrospective study where data were collected from patient records
Erasmi 1996	The trial was performed in patients having femoro‐popliteal bypass both above and below the knee. Outcomes for the above‐ and below‐knee subgroups were not reported so it was not possible to include the trial
Hamann 1998	Randomisation technique unclear, above‐knee, below‐knee and distal bypasses inseparable (English title states above‐knee but methods talk about below‐knee bypass)
Hobson 1980	Case series, not randomised trial data
Johnson 2000	Inadequate randomisation process. Quote: "the choice between a PTFE and HUV bypass graft was randomized in the operating room, initially to favour saphenous vein." The data were presented as vein versus HUV versus PTFE and was inseparable for analysis
Kreienberg 2002	Bypass to any below‐knee artery, not just popliteal. Randomisation technique unclear
Kumar 1995	Unclear randomisation process. Results never fully published in paper form, only as two abstracts. Data presented as vein versus PTFE versus Dacron and were inseparable for analysis
Lindholt 2011	The trial was performed in patients having femoro‐popliteal bypass both above and below the knee. Outcomes for the above‐ and below‐knee subgroups were not reported so it was not possible to include the trial
Linni 2015	The trial was performed in patients having femoro‐popliteal and more distal bypass. Outcomes for the subgroups of patients with distal anastomosis the above‐knee popliteal or below‐knee popliteal artery were not reported so the study could not be included
Lundgren 2013	The trial was performed in both patients having femoro‐popliteal bypass below the knee and patients having femoro‐distal bypass. Outcomes for the subgroup having femoro‐popliteal bypass alone were not reported
McCollum 1991	Unable to separate above‐ and below‐knee data
Midy 2016	Trial failed to recruit 30% of planned patients, and lost 26% of these to follow up. Results only presented at 5 years follow‐up using an unusual system to impute missing data
Moody 1992	Unable to separate above‐ and below‐knee data
Motta 1989	Above‐knee, below‐knee and distal bypasses inseparable; unclear randomisation
NCT00617279	Trial terminated by sponsor due to slow recruitment. No results available
NCT00845585	Trial withdrawn prior to enrolment of any patients
Robinson 1999	Unable to separate above‐ and below‐knee data. A proportion of both above‐ and below‐knee anastomoses included endarterectomies and or vein cuffs which the study authors concede produced a significant difference in patency without giving detailed subgroup analysis. Unclear randomisation
Robinson 2003	Unable to separate above‐ and below‐knee data. Below‐knee anastomotic site described as 'distal' in some cases without detailed anatomical description. A proportion of both above‐ and below‐knee anastomoses included endarterectomies and or vein cuffs which the study authors concede produced a significant difference in patency without giving detailed subgroup analysis. Unclear randomisation
Schulman 1987	Patients received both above‐ and below‐knee bypass grafts but results presented together. Poor randomisation (month of birth)
Tilanus 1985	Unable to separate above‐ and below‐knee data. Unclear randomisation technique
Veith 1986	Unable to separate above‐ and below‐knee data. Inadequate randomisation (hospital number, card pulling, random number generator)
Watelet 1997	The trial was performed in patients having femoro‐popliteal bypass both above and below the knee. Outcomes for the above‐ and below‐knee subgroups were not reported so it was not possible to include the trial
Zilla 1994	Unable to separate above‐ and below‐knee data, not intention to treat. Inadequate randomisation (random number generator, concealment not stated)

CCT: clinically controlled trial
 HUV: human umbilical vein
 PTFE: polytetrafluoroethylene
 RCT: randomised controlled trial