Frequently Asked Questions

Do you have questions that aren’t answered here? Contact us at cosmid@uw.edu or (800) 972-4956.


Q: What happens if I decide to not participate in the study?

A: You are not required to join the COSMID trial. No matter what you choose, your doctor and healthcare team will work with you to help you get better.


Q: What does surgery involve? What are the risks?

A: During surgery, the part of the colon affected by diverticulitis is removed. The remaining ends of the colon are reconnected. Most patients spend 3 to 5 days in the hospital. During this time, doctors and nurses work with patients to control their pain and make sure they can eat and drink before going home.

Potential Risks of Surgery:

  • Any surgery has risks. The most serious and rare problems may include:
    • Infections or bleeding;
    • Leaking from the intestine where part of the colon was removed;
    • Needing a colostomy, where the colon is brought out to the skin to drain into a bag;
    • Damage to areas near the colon such as the tube that carries urine; and
    • Death (very rare).
  • More common problems are infection where the skin was cut and a longer than expected time spent in the hospital.

Despite the risk of problems, surgery is considered safe and is one of the accepted approaches to treating diverticulitis.


Q: How long will I be in the hospital after surgery?

A: Most patients spend 3 to 5 days in the hospital. While you are in the hospital, your doctors and nurses will work with you to control your pain and make sure you are able to eat and drink before you go home.


Q: What about medical management? What are the risks?

A: Medical management may include:

  • Getting regular exercise;
  • Eating a high fiber diet;
  • Taking supplements like fiber and probiotics; and/or
  • Taking certain prescription drugs.

We think of these as tools in a medical management toolbox. Not everyone with diverticulitis will use all of these tools.

Potential Risks of Medical Management:

  • All the tools in the toolbox have been shown to improve symptoms or to lower the chance of diverticulitis coming back, for some people.
  • The tools do not work for everyone.
  • Some insurance companies may not pay for all of the tools.
  • Each of the tools has its own risks. Most risks are small. For example, antibiotics can cause a form of diarrhea called c. diff that can be treated. This does not happen often.

The medical management toolbox is low risk and may make symptoms of diverticulitis better. But it’s not clear if these tools will keep diverticulitis from coming back.


Q: Will COSMID trial participants be paid?

A: We recognize that your time is valuable. COSMID trial participants will be paid each time they complete a study survey. We will also share results of the trial with you once the study is completed.


Q: My treatment will be randomly chosen? What does that mean?

A: If you join the COSMID trial, your treatment will be assigned randomly by a computer. You will have an equal chance of each treatment. Studies like this, called randomized trials, are done when we need the best possible evidence to help doctors and patients decide what is best for them. Both treatment options are commonly used, and both are safe. Neither treatment is experimental.


Q: If I decide to participate in COSMID but don’t like the treatment chosen for me, can I change my mind?

A: You are in charge of your treatment. If you decide you don’t want the treatment that is randomly chosen for you, you do not have to go through with it. We may still want to ask you questions about your experiences with the treatment you do choose, if you tell us that we can contact you.


Q: Where do I have to go for my treatment?

A: You will continue to see your doctor while you participate in the COSMID trial. You and your doctor will make decisions about your treatment together. The COSMID trial team will contact you to ask about your experiences and feelings about your treatment.


Q: How often will you contact me?

A: We will send you surveys to complete every 3 months for 3 years after your treatment.