Salz 1980.

Methods	Study design: double blind randomised cross‐over study. Method of randomisation: assigned at random.
Participants	Country: Germany. Setting: not stated. Number randomised: 29, treatment group 13, control group 13. Age: mean age males 69.0, mean age females 64.4. Sex: 11 males and 18 females. Inclusion criteria: Patients with PAD (stage IIb according to Fontaine) in both legs. Exclusion criteria:not stated.
Interventions	Treatment: 40 mg standardised Egb 761 two times daily 2 tablets. (Rökan®). Control: placebo. Duration: two times 6 week cross‐over study.
Outcomes	Walking distance: ACD and ICD assessed by walking with 2 steps per second; Ratschow‐test; maximal time of toe‐standing; temperature of the skin; laboratory parameters.
Notes	Only the first study period (6 weeks) before the cross‐over is considered. Funding: Not stated.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Patients were assigned to the trial according to a random code van 1 to 30 in a consecutive way.
Allocation concealment (selection bias)	Unclear risk	Insufficient information.
Blinding (performance bias and detection bias) All outcomes	Unclear risk	Insufficient information.