Twenty-eight RCTs (16 to 500 patients per study) were included in the review. Most trials randomised limbs rather than individuals. Follow-up ranged from one week to five years. In the quality assessment 83% of studies reported intention-to-treat analysis, 78% reported allocation concealment and absence of selective outcome reporting and 43% reported blinding for the quality assessment. Only seven trials scored "yes" for random sequence generation. There was no evidence of publication bias for all comparisons of primary failure except for endovenous laser ablation versus surgery.
Primary failure: There were no statistically significant differences in failure rate of endovenous laser ablation and radiofrequency ablation compared with surgery. Ultrasound-guided foam sclerotherapy showed twofold higher risk of failure compared to surgery (RR 2.4, 95% CI 1.6 to 3.6; Ι²=22.7%). Comparison of radiofrequency ablation and endovenous laser ablation produced similar results.
Clinical recurrence: No significant difference results were found for the rate of clinical recurrence in endovenous laser ablation and radiofrequency ablation versus surgery.
Venous clinical severity score: There was no statistically significant difference between endovenous laser ablation and surgery for venous clinical severity score.
Postoperative complications: One or more of the endovenous techniques had advantages over surgery in lowering wound infections (RR 0.3, 95% CI 0.1 to 0.8; Ι²=0% for endovenous laser ablation) and haematoma (RR 0.5, 95% CI 0.3 to 0.8; Ι²=9.9% for endovenous laser ablation and RR 0.4, 95% CI 0.1 to 0.8; Ι²= 64.2% for radiofrequency ablation). No significant differences were found for paraesthesia and ecchymosis but there was a higher risk of superficial thrombophlebitis for radiofrequency ablation technique compared to surgery (RR 2.3, 95% CI 1.1 to 5.0; Ι²=8.2%).
Postoperative pain, return to normal activity or work and quality of life: Endovenous techniques were associated with reduced first recorded postoperative pain (MD -0.6, 95% CI -1.1 to -0.2; Ι² =31.7% for endovenous laser ablation and MD -1.6, 95% CI -2.1 to -1.1; Ι²=0% for radiofrequency ablation) and faster return to normal activities or work (MD -4.9 days, 95% CI -7.1 to -2.7; Ι²=86.9% for radiofrequency ablation) compared with surgery. There was no statistically significant difference between endovenous laser ablation and surgery for quality of life.
Further subgroup and sensitivity analyses were reported.