Study characteristics
An overview of the included articles, study design, sample size, population characteristics, measurement tools, results and factors correlated to anxiety and depression in endometriosis patients is listed in the appendix S2 [27-73]. We have included 41 studies with a cross-sectional design, three longitudinal cohort studies and three retrospective cohort studies. Most studies (52%) originated from Europe, 26% from the United States of America or Canada, 15% from South and central America. The remaining articles (7%) originated from Asia, Africa or Oceania. Eleven of the included studies were published in the current year 2020.