Development and validation of a Vein Assessment Tool (VAT).

OBJECTIVE: To assess the face validity and the inter-rater reliability of the Vein Assessment Tool (VAT) for classifying veins according to their level of intravenous insertion difficulty.

DESIGN: Prospective observational study.

PARTICIPANTS: Eight nurses and two radiographers from the Medical Imaging Department and five nurses from the Haematology Day Patient Unit of a large tertiary hospital.

INTERVENTION: Assessments of veins in the upper limb were undertaken independently by nurses from two departments of a major tertiary hospital.

MAIN OUTCOME MEASURE: Level of inter-rater agreement assessed using intraclass correlation coefficients (ICC).

RESULTS: A total of 125 independent assessments were made by 15 nurses. The mean percentage agreement between raters from Medical Imaging was 84% (SD 10.7; range 60% to 100%) and between raters from Oncology was 92% (SD 17.9; range 60% to 100%). The inter-rater reliability was very high for the ten medical imaging raters 0.83 (95% confidence interval CI = 0.61 - 0.95) and for the Oncology raters 0.93 (95% CI = 0.77-0.99).

CONCLUSION: The Vein Assessment Tool (VAT) has been validated by a sample of nurses with cannulating experience. Following broader testing it may be useful for research studies or by nurses who wish to objectively describe the condition of a vein for clinical purposes.