EP23.25: Simple rules versus expert opinion: a meta‐analysis comparing performance of methodical assessment to subjective assessment for evaluating adnexal masses

To compare the diagnostic performance of a binary methodical assessment, IOTA Simple Rules (SR), and expert subjective assessment (SA) in evaluating for malignancy in known adnexal masses. The MEDLINE database was used to search for primary data comparing techniques for assessing known adnexal masses for malignancy. To account for recent advances in ultrasound technology and the evolving medical knowledge regarding the presentation of adnexal masses, the search was limited to articles published between 2016 and 2024. Inclusion criteria involved adnexal masses which had been evaluated by an expert sonographer using the SR model for methodical assessment or by an experienced physician using subjective assessment. Of 204 articles found in the original search, 19 were included in this meta-analysis. The results for 6,012 adnexal masses were extracted and compared. All masses were ultimately confirmed by postoperative pathology which represents the true outcomes in this study. Masses that did not fit into either category (benign or malignant) using SR were classified as malignant. SA exhibited a sensitivity of 89.4% and a specificity of 96%, while SR assessment demonstrated a sensitivity of 86.3% and a specificity of 90.5%. The p-values for sensitivity comparison and specificity comparison were 0.0065 and <0.001 respectively. With alpha set at 0.05, these results indicate that SA had significantly higher sensitivity and specificity compared to SR assessment. These findings raise questions about the potential influence of diagnostic criteria like simple rules on the subjective assessment of adnexal masses by physicians. The significantly higher sensitivity and specificity observed with the SA group suggest the possibility that clinicians may subconsciously utilise diagnostic criteria similar to simple rules when subjectively assessing adnexal masses via ultrasound. Further research is warranted to explore this phenomenon and its implications for clinical practice.