Appendicitis Study (CODA)

Comparing Outcomes of Drugs and Appendectomy (CODA) is a large-scale randomized clinical trial to evaluate two ways to treat uncomplicated appendicitis—appendectomy and antibiotics—in patients at participating hospitals in Washington and California.

The CODA trial focuses on clinical outcomes—broadly agreed, measurable changes in health or quality of life—as well as the patient-reported outcomes (PROs) that matter most to patients. Results of this study will support an evidence-based approach to appendicitis care and help nearly 300,000 Americans each year make an important healthcare decision about this common condition.


Research reported in this website was funded through a Patient-Centered Outcomes Research Institute (PCORI) Award (1409-24099).

CODA Study by the Numbers

  • Recruiting 1,552 patients
  • 8 participating hospitals
  • Following patients for 2 years to track outcomes