Jensen 2007.

Methods	Site: Femoral to AK popliteal (POPUP study) Study design: RCT Method of randomisation: randomisation envelopes Blinding: unblinded, intention to treat Exclusions post randomisation: 13 (8 Dacron, 5 PTFE) Losses to follow up: 51 (12%)
Participants	Country: Scandinavia Setting: hospital (13 departments) No. of participants: 426 (413 for analysis due to exclusions; 205 PTFE, 208 Dacron) Age (mean): 66 yrs Sex: 152 males, 261 females Inclusion criteria: "chronic lower limb ischaemia" Exclusion criteria: less than 18, pregnant, could not obtain informed consent
Interventions	6 mm PTFE and 6 mm Dacron graft Anticoagulation as per individual centre protocol
Outcomes	Primary patency, secondary patency and limb survival
Notes	No common anticoagulation pathway. Multiple, different surgeons
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Grafts were contained in envelopes, however the randomisation procedure is unclear. Probably done as other papers from this unit clearly use random sequences (Eiberg 2006; Vogt 2007)
Allocation concealment (selection bias)	Low risk	Quote: "Immediately before surgery, the graft material was selected by a pre‐processed sealed envelope. Randomisation was stratified for each centre."
Blinding of participants and personnel (performance bias) All outcomes	High risk	Operative blinding impossible in this type of trial
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Outcome assessors and patients not obviously blinded
Incomplete outcome data (attrition bias) All outcomes	Low risk	No losses, clear life table data
Selective reporting (reporting bias)	Low risk	All stated outcomes reported
Other bias	Unclear risk	Anticoagulation as per individual centre protocol and therefore inconsistent