Grimm 2001.

Methods	Study design: single centre, randomised controlled trial with 2 parallel groups. No power calculation.
Participants	Country: Germany Sample size 53: 32 males, 21 females Mean age (SE) years: experimental group 70.5 (9.8) years, control group 68.1 (8.4) years Inclusion criteria Intermittent claudication. Femoro‐popliteal lesion at least 1cm distal to the common femoral artery bifurcation with normal mid and distal popliteal artery. Lesion: stenosis > 70% of vessel diameter and < 5cm in length. Exclusion criteria Lesion > 5cm, multifocal disease, occlusions not negotiated by guidewire, mid‐popliteal disease or poor run off, fresh thrombus or contraindications for surgery or anticoagulation.
Interventions	Experimental group: balloon angioplasty and Palmaz stent, n=30 Control group: balloon angioplasty, n=23
Outcomes	Primary outcome: arterial restenosis Secondary outcomes: maximum walking distance, number of additional procedures, ABPI Follow‐up regime: clinical examination and duplex scan at 3, 6 and 12 months followed by annual review thereafter for both groups. Experimental group participants in addition each underwent angiography at 6 months. Primary and secondary patency rates after 12, 24 and 39 months in both groups. Maximum follow‐up period of 39 months for both groups.
Notes	Recruitment period: not stated Only experimental group offered peri‐operative i.v. heparin bolus of 5000 units and 1g aspirin. All patients received i.v. heparin for 24 hours after the procedure and 100mg/d aspirin for the remainder of their lives. Mean follow up: experimental group 20.9 months, control group 29.1 months.
Risk of bias
Bias	Authors' judgement	Support for judgement
Adequate sequence generation?	Unclear risk	"The written result of the randomization was sealed in an envelope, which was numbered according to the patient's number".
Allocation concealment?	Unclear risk	Sealed envelopes. Not clear if opaque envelopes. The envelope was opened after diagnostic angiography.
Blinding? All outcomes	High risk	There was no mention of blinding.
Incomplete outcome data addressed? All outcomes	Unclear risk	Intention‐to‐treat analysis not stated. Losses during follow‐up period were given but no information given on the statistical handling of missing data.
Free of selective reporting?	Low risk	All measures of technical and clinical success reported.
Free of other bias?	Low risk	No significant difference between groups of baseline risk factors or clinical status.