EP23.24: ADNEX versus simple rules: a meta‐analysis comparing the performance of a quantitative test to a binary test for differentiating adnexal masses

To compare the sensitivities and specificities of two IOTA ultrasound models, the quantitative ADNEX test and the binary Simple Rules (SR) test in differentiating between benign and malignant pathology in known adnexal masses. This meta-analysis used the MEDLINE database to find primary articles which compared various models of evaluating adnexal masses for malignancy. To account for recent advances in ultrasound technology, the search was limited to articles published between 2016 and 2024. 204 articles were investigated by one reviewer for adnexal masses which were assessed using ADNEX without CA-125 or SR and confirmed by postoperative pathology. Across the 26 articles which met inclusion criteria, the results of assessments for 9,058 adnexal masses were extracted and compared using ultrasound classification as test outcomes and postoperative pathology as true outcomes. The cutoff value for malignancy using ADNEX was 0.10 for all masses. Masses that did not fit into either category (benign or malignant) using SR were classified as malignant. ADNEX demonstrated a sensitivity of 91.3% and a specificity of 84.1%, while SR exhibited a sensitivity of 86.3% and a specificity of 90.5%. Statistical analysis revealed significant differences between ADNEX and SR in both sensitivity and specificity. The p-value for sensitivity comparison was < 0.00001, indicating that ADNEX had a significantly higher sensitivity compared to SR. Similarly, the p-value for specificity comparison was also < 0.00001, signifying that SR showed significantly superior specificity over ADNEX. These findings underscore the importance of choosing the appropriate ultrasound criteria for the evaluation of adnexal masses. While ADNEX offers higher sensitivity, SR demonstrates superior specificity. Clinicians should consider these differences when selecting the most suitable approach for the diagnosis and management of adnexal masses in clinical practice.