Veterans Study.
| Methods | Study design: randomised, not blinded Method of randomisation: using a method of stratification to balance two factors: symptoms (claudication vs rest pain); and level of disease requiring treatment (iliac vs femoro‐distal) Exclusions postrandomisation: eight randomised participants in the surgery group were not treated because of an intervening event, and 2 randomised to PTA refused to give consent and were not treated. In addition, eight treated participants withdrew Losses to follow up: 20 | |
| Participants | Country: USA Number of participants: 263 Sex: male Age: mean age 61.5 years (191 participants with IC and 72 CLI; 163 had iliac disease and 100 femoro‐popliteal disease) Inclusion criteria: 1) angiographically demonstrated significant stenosis (≥ 80%) or occlusion, < 10 cm in length in the iliac, superficial femoral, or popliteal arteries; 2) ABI of affected leg 0.9 or less at rest; 3) symptoms in the affected leg of either claudication (less than 2 blocks and preventing daily activities), rest pain, or impending gangrene; 4) considered suitable for treatment by both the vascular surgeon and the radiologist Exclusion criteria: contraindication to a short course of heparin, life expectancy of less than 3 years, medical contraindications to major surgery or unwilling to participate | |
| Interventions | Treatment: bypass surgery (details of the technical performance of the intervention were left to the discretion of the individual surgeon) Control: PTA Duration: median 4.1 years (range 2 to 6 years) | |
| Outcomes | Mortality Treatment failure Primary and secondary patency ABI Amputation rate Subjective measure (Sickness Impact Profile scores) | |
| Notes | This study was supported by the Cooperative Studies Program of the Medical Research Service, Department of Veteran Affairs Central Office, Washington, DC. | |
| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Unclear risk | Quote: "After consent was obtained, the participating hospital contacted the study biostatistician by phone for treatment assignment. Randomization was stratified by center and for each of four disease categories". Comment: Unclear method for randomisation. |
| Allocation concealment (selection bias) | Low risk | Central allocation (see quote above). |
| Blinding (performance bias and detection bias) All outcomes | Low risk | See below. |
| Blinding of participants and personnel (performance bias) All outcomes | Low risk | Most probably no blinding, but the nature of interventions rendered blinding not feasible. |
| Blinding of outcome assessment (detection bias) All outcomes | Low risk | No blinding of outcome assessment, however outcome measures were not likely to be influenced by the lack of blinding. |
| Incomplete outcome data (attrition bias) All outcomes | Unclear risk | Insufficient reporting of attrition/exclusions to permit judgement |
| Selective reporting (reporting bias) | Unclear risk | Insufficient information to permit judgement |
| Other bias | Low risk | No other source of bias was identified. |
ABI: ankle brachial index BP: blood pressure CLI: critical limb ischaemia GP: General Practitioner IC: intermittent claudication m: meter MWD: maximal walking distance NHS: National Health Service PTA: percutaneous transluminal angioplasty PTFE: polytetrafluoroethylene rt‐PT: recombinant tissue plasminogen activator SD: standard deviation SFA: superficial femoral artery SVS/ISCVS: Society for Vascular Surgery/International Society for Cardiovascular Surgery TASC: Trans‐Atlantic Inter‐Society Consensus Document on Management of Peripheral Arterial Disease