Prospective Multi-center Study of Reliability in Vascular Laboratory Testing of Venous Reflux Phase 1 of the INVEST study (INvestigating Venous Evaluation and Standardization of Testing) Fedor Lurie

Goal: development of standard protocols for noninvasive venous testing Reliability: –Repeatability –Reproducibility –Comparison of methods (agreement) INVEST INvestigating Venous disease Evaluation and Standardization of Testing Sponsored by The American Venous Forum Foundation

Methods Subjects: –A total of 74 participants from 11 centers –Mean age was 50 years (range: 22 to 79) –17 of the participants were healthy volunteers. –57 patients with Ep, Pr, and various combinations of A –Clinical class: C2 – 20 patients C3 – 10 patients C4 – 16 patients C5-6 – 11 patients

Repeatability of reflux time measurements * P 0.05 **P < 0.01

REPRODUCIBILITY ReproducibilityFacilitated Reproducibility 95% LA +/ % LA +/- 0.59

Agreement (%) between interpretations of two replicated studies performed with different methods.

Conclusions Repeatability of duplex ultrasound in detection of venous reflux is high. Reproducibility of this test is sufficient and can be improved by educational intervention. Testing patients at a different time of the day, in different positions, and using different reflux- provoking maneuvers significantly decreases reliability.

Conclusions Standardization of duplex ultrasound protocol can improve reliability. –Reports should include information on: the time of the test the position of the patient the provoking maneuver used. Adopting a uniform criterion of 0.5 sec for pathological reflux can significantly improve the reliability of reflux measurement and interpretation. –The repeated scans can be performed in the same settings, improving reliability.