Hoss 2020.

Study characteristics
Methods	Study design: prospective, randomised, double‐blind, split‐leg, single‐centre clinical trial Method of randomisation: not mentioned Blinding: participant ‐ yes; treating doctor ‐ yes; outcome assessors ‐ yes Power calculation: not mentioned Total number of participants: 30 Total number of procedures: 60 Treatment localisation: leg veins Number of exclusions post‐randomisation: none Number of withdrawals and reasons: none
Participants	Setting: outpatient site Country: USA Gender: women Age: mean 53.6 (32 ‐ 70 years) Inclusion criteria: varicose, reticular or telangiectatic leg veins, or both Exclusion criteria: CEAP class C2 or greater, history of DVT, pregnancy, allergy
Interventions	Treatment 1: sclerotherapy with POL:air ratio 1:2 Treatment 2: sclerotherapy with POL:air ratio 1:4
Outcomes	Efficacy was rated on a quartile percentage scale (1 = 0% – 25%, 2 = 26% – 50%, 3 = 51% – 75%, and 4 = 76% – 100%) Adverse events: erythema, pigmentation,urtication/swelling, ankle/pedal oedema, ecchymosis, ulceration, matting, hyperpigmentation
Funding sources	No details provided
Declarations of interest	None declared
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No details given
Allocation concealment (selection bias)	Unclear risk	No details given
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Both participants and evaluating investigators were blinded to the randomisation schedule
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Both participants and evaluating investigators were blinded to the randomisation schedule
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	No details given
Selective reporting (reporting bias)	Unclear risk	No details given
Other bias	Unclear risk	No details given