International Endometrial Tumor Analysis (IETA) terminology for the evaluation of endometrial color flow and vascular pattern in women with abnormal uterine bleeding – a reproducibility study among ob-gyn ultrasound subspecialists in a tertiary training hospital

Abstract

BACKGROUND: The International Endometrial Tumor Analysis (IETA) group developed a catalog of standardized terms to describe findings that may be associated with uterine pathology. However, there is a lack of reliability studies for these descriptors in the literature. OBJECTIVE: The objective of this study was to estimate interobserver and intraobserver reliability with regard to the IETA group descriptors for endometrial vascular characteristics in women with abnormal uterine bleeding. MATERIALS AND METHODS: Five nonexpert and five expert raters assessed stored still images of transvaginal ultrasound examinations obtained from 68 women with abnormal uterine bleeding and endometrial thickening. Endometrial vascularity was evaluated using the IETA group descriptors for color flow and vascular pattern. Interobserver agreement was estimated by comparing the assessments of the nonexpert and expert raters. Intraobserver agreement was estimated by repeating the raters’ assessment after 4 weeks. Interrater agreement to the subjective assessment of an expert investigator was also computed. RESULTS AND CONCLUSION: The reproducibility of assigning IETA color score is good regardless of the degree of expertise of the rater, although the experts displayed better interobserver reliability (κ = 0.74 vs. 0.57) and intraobserver reliability (κ = 0.84 vs. 0.63). However, the reproducibility of describing IETA vascular patterns is significantly worse for both expert and nonexpert raters in both interobserver reliability (experts κ = 0.49 vs. 0.34) and intraobserver reliability (experts κ = 0.65 vs. 0.42). Both expert and nonexpert raters exhibited acceptable agreement with the reference standard, with experts performing better for both color score (κ = 0.79 vs. 0.70) and vascular pattern (κ = 0.63 vs. 0.44).