The COSMID trial is a study comparing two ways to treat a condition called diverticulitis, which is when the small pouches in your digestive tract become inflamed. The two treatments are elective colectomy (a surgery to remove part of the colon) and best medical management (using medicines and lifestyle changes like fiber supplements and probiotics to manage symptoms). The study aims to see which treatment helps improve patients' quality of life more. People can join the main study, where they will be randomly assigned to one of the treatments, or they can join an observational group if they don’t want to be randomized but still want to share their health outcomes.

• The study will take place at multiple locations.
• Participants must be adults and have had at least one episode of diverticulitis.
• Participants will be required to complete surveys and attend follow-up visits.

Before joining, check if you meet the eligibility requirements. Some reasons you might not be eligible include having had previous surgery for diverticulitis or certain medical conditions that make surgery risky.