Supplementary Material for: Detecting Endometriosis in Adolescents: Why Not Start from Self-Report Screening Questionnaires for Adult Women

<i>Background:</i> Endometriosis in adolescent girls is often diagnosed after a long delay. This diagnostic delay can be associated with more advanced stages of endometriosis and with a higher likelihood of fertility problems at a later age. <i>Material and Methods:</i> A systematic review of literature and quality assessment was performed in order to identify questionnaires that were developed to identify adult women with endometriosis. Based on these questionnaires, specific questions that had been reported to be predictive for endometriosis were selected and included in a newly composed questionnaire with the aim to identify adolescents at risk of developing endometriosis. <i>Results:</i> Based on the literature, we identified 5 questionnaires developed to identify adult women with endometriosis; this questionnaire contained 6 questions that had been reported to be predictive for adult endometriosis. These questions query age of menarche, cycle duration, dysmenorrhea, pain descriptors, dyschezia and urinary symptoms and were combined into a new self-report questionnaire aimed to identify adolescents at risk to develop endometriosis. <i>Conclusion:</i> We developed a self-report questionnaire aimed to identify adolescents at risk to develop endometriosis based on questions from self-report questionnaires that have been reported to identify adult women with endometriosis.