Cohort profile: The Endometriosis pain QUality aftEr Surgical Treatment (EndoQUEST) Study.

Endometriosis affects reproductive-aged females and varies considerably in terms of symptom presentation, morphologic features, and treatment response. Most studies investigating symptom recurrence after an endometriosis-related surgery have been conducted among adults. The Endometriosis pain QUality aftEr Surgical Treatment (EndoQUEST) Study was established to assess characteristics and biomarkers that are associated with pain remediation and improved quality of life after an endometriosis-related surgery among adolescents and young adults. This paper describes the EndoQUEST methodology, summarizes baseline descriptive factors, and compares characteristics by participant retention status. We enrolled 100 surgically-confirmed endometriosis participants aged 12-23 years who provided questionnaire data on reproductive and behavioral factors, pain characteristics and quality of life at three time points; before surgery, 6 weeks to 26 weeks after surgery, and 1 year after surgery. Among these 100 participants, 88 provided blood and/or saliva at all three time points, while 12 provided blood and/or saliva samples only before surgery and 6 to 26 weeks after surgery. There was little evidence of lost to follow-up at 1 year after surgery due to pain symptoms, as pain and quality of life characteristics were similar between participants who completed the questionnaire 1 year after surgery and those who did not. Analyses utilizing these longitudinal data will advance personalized treatment decision making for adolescents and young adults with endometriosis.