Kiesewetter 1997.

Study characteristics
Methods	Study design: randomised, double‐blind, placebo‐controlled Method of randomisation: not stated Exclusions post randomisation: not stated Losses to follow‐up: not stated
Participants	Country: Germany Setting: university Number: 81 patients Age: mean 59 ± 7 years Gender: 26 M:55 F Inclusion criteria: stage I to II of Wert CVI Exclusion criteria: acute thromboses; ulcus cruris; heart insufficiency; recent venous surgery; venoactive drugs
Interventions	Treatment: 500 mg Buckwheat herb and 30 mg troxerutin. 2 tablets 3 × per day Control: placebo Duration: 84 days Follow‐up: 112 days
Outcomes	Primary Lower leg volume determined by ultrasound of the more affected leg Secondary Symptoms ‐ pain, paraesthesia, cramps, swelling, restless legs, burning feet measured by an ordinal scale (0 to 2)
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "For randomization of patients, the program was 'Rancode' of the company IDV data analysis and experimental design, Gauting, used" Comment: computerised generation of a random sequence generally accepted as a fair method of randomisation
Allocation concealment (selection bias)	Unclear risk	Comment: no information given about methods used for allocation concealment
Blinding (patients)	Low risk	Quote: "The same number of identical‐looking placebo tablets consisting of lactose were given" Comment: Identical placebo ensures double‐blinding
Blinding (study researchers)	Low risk	Quote: "The same number of identical‐looking placebo tablets consisting of lactose were given" Comment: Identical placebo ensures double‐blinding
Blinding (outcome assessment)	Low risk	Quote: "The same number of identical‐looking placebo tablets consisting of lactose were given" Comment: Identical placebo ensures double‐blinding
Incomplete outcome data	Unclear risk	Comment: number of participants in each group described. No information provided about participants who prematurely dropped out of the study
Selective reporting	Low risk	Comment: no published protocol identified, and no differences between outcomes reported in the methods section and those reported in the results section
Other bias	Low risk	Comment: none detected