Diagnosis of pelvic endometriosis: A systematic review and accuracy meta-analysis of non-invasive tests available in primary care

Abstract

Background: Endometriosis is a chronic, often debilitating condition with a current significant delay from symptom onset to diagnosis with much of this in primary care. Methods: A systematic review and meta-analysis of the primary literature was conducted to investigate the accuracy of symptoms, clinical history and first-line non-invasive tests to predict pelvic endometriosis (PROSPERO: CRD42020187543). We searched Medline, Embase, Web of Science and Scopus from conception (1966; 1972; 1997; 2004 respectively) to September 2022 for primary test accuracy studies assessing non-invasive tests against reference standard diagnosis for endometriosis. Two authors independently conducted data extraction and quality assessment. Grading of evidence was performed using a novel visual pentagon model. Meta-analyses of test accuracy was estimated using bivariate random effects models. Results: The 125 included studies (250,574 participants) showed mixed quality. Studies applying non-surgical (database/self-reporting) reference standard had a greater risk of bias. In 98 studies applying surgical reference standard, summary diagnostic odds ratios for endometriosis were: dysmenorrhoea 2.56 (95% confidence interval 1.99-3.29); pelvic pain 2.56 (1.73-3.74); dyschezia 2.05 (1.36-3.10); dyspareunia 2.45 (1.71-3.52); family history of endometriosis 6.79 (4.08-11.3); nulligravidity of 2.01 (1.62-2.50); body mass index (BMI) ≥30kg/m2 0.37 (0.19-0.68); trans-vaginal ultrasound scan (TVUSS) endometrioma 91.2 (44.0-189); TVUSS invasive endometriosis 26.1 (9.28-73.5); and cancer antigen-125 (CA-125) >35U/mL 16.0 (8.09-31.7). Sensitivity analysis excluding all high-risk studies found concordant results. Conclusions: This meta-analysis collated the performance of non-invasive tests for endometriosis across a comprehensive and geographically varied population. Study quality was mixed, however results were consistent with high-risk studies excluded. These findings will inform future prediction models for triage in primary care.