In a long-term follow-up study comparing saphenofemoral ligation and stripping with endovenous laser ablation, the groin is examined yearly by duplex ultrasound (DUS) to detect postoperative varicose vein recurrence. Clear criteria are needed for the uniformity of DUS observations. Physicians taking care of the follow-up were evaluated by an intra- and interobserver analysis. DUS films of 22 patients with no recurrence and 22 patients with recurrence of varicose veins were twice interpreted in two sessions. Observations were analysed by a kappa test. Interpretations of DUS by experienced observers show a kappa >7. Improved kappa results were measured over time in our physician in training. In conclusion, the reproducibility of DUS studies performed by the experienced observers of the study is excellent.
Keywords: duplex ultrasound; intra- and inter-observer reproducibility; recurrence; varicose veins.