Intervention: Rectal barostat test. All participants will have the rectal barostat test, but the order of tests will be clinical trials

A comparison of two medical devices that assess how people sense the need to empty their bowels

This study compares two ways to check how your body senses needing to empty your bowels. It uses two devices, an elastic balloon and a non-elastic one, to see if they give the same diagnosis for common bowel problems like constipation or urgency. This helps improve diagnosis and treatment.