Hierarchy of evidence for endometriosis diagnosis and surgery.

Without an animal model and a non-invasive diagnosis, the pathophysiology of endometriosis is unclear and information is limited to symptomatic women. Lesions are biochemically variable. Medical therapy cannot be blinded and extensive surgery combines low numbers with variable difficulty and surgical skills. Experience is spread among specialists in imaging, medical therapy, infertility, pain and surgery. Besides the recent changes in interpreting statistical analyses, the limited good-quality evidence increases the importance of clinical experience. Therefore trial design, analysis and judgment of results should be done by experts in the different disciplines of endometriosis, before being translated into guidelines.