Hepp 1992.

Study characteristics
Methods	Study design: double‐blind, randomised Country: Germany Setting: 9 centres Intention‐to‐treat: not mentioned
Participants	Number of participants randomly assigned: 195 (98 pentoxifylline, 97 PGE1) Number of participants analysed: 195 Exclusions postrandomisation: 0 Losses to follow‐up: 0 Age (mean): 65 years Sex: male:female: 2.8:1 Inclusion criteria: PFWD 50–200 m; stable stadium Fontaine IIb for 6 months; diagnosis of stenosis through digital subtraction angiography or conventional angiography of lower limbs; signing an informed consent form; variance of walking distance at beginning < 20% Exclusion criteria: pregnancy; present heart failure; kidney failure; prestenosis (e.g. stenosis of the aorta abdominalis or iliacal arteries); necrosis or rest pain; pulmonary insufficiency; arthrosis; MI within previous 6 months; orthostatic dysregulation and experiencing collapse; severe cardiac rhythm problems; epilepsy
Interventions	Treatment: IV pentoxifylline, 200 mg bid Control: IV PGE1, 40 µg bid Duration: 4 weeks
Outcomes	Primary: mean TWD and PFWD Secondary: side effects
Notes	Treadmill protocol: not specified Mean PFWD and TWD expressed in metres only
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "randomisation list." Comment: no other information provided.
Allocation concealment (selection bias)	Unclear risk	Not mentioned.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Quote: "blind." Comment: no other information provided.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not mentioned.
Incomplete outcome data (attrition bias) All outcomes	Low risk	No incomplete outcome data.
Selective reporting (reporting bias)	Unclear risk	Protocol not available; insufficient information available to permit judgement.
Other bias	Low risk	Study appeared free of other bias.