Final Research Report
This project's final research report is expected to be available by July 2023.
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PCORI-Funded Study Examining Treatment Options for Appendicitis Yields Useful Early Results
This PCORI-funded study comparing surgery versus antibiotics for uncomplicated appendicitis released early results that physicians and patients can use when weighing treatment options, especially during the coronavirus pandemic.
Behind The Knife: The Surgery Podcast (October 5, 2020)
In this episode, Principal Investigator David Reed Flum, MD, MPH, and members of his team discuss the early results of the trial. Listen on Apple Podcasts / Spotify
CODA Appendicitis Study
University of Washington
Related PCORI Dissemination and Implementation Project
Article Highlight: At least in the short term, using antibiotics to treat appendicitis worked as well as surgical removal of the appendix for most patients in the CODA trial, as reported in the New England Journal of Medicine. Health outcomes associated with each treatment were similar. More than 70 percent of patients on antibiotics avoided having surgery and missed less time away from work or school in the three months post-treatment. However, nearly 30 percent who received antibiotics ultimately needed surgery. CODA was conducted at 25 sites nationwide and involved a wider range of patients than previous studies, making its results more broadly applicable to typical patients with appendicitis.
Results of This Project
Related Journal Citations
Peer review of PCORI-funded research helps make sure the report presents complete, balanced, and useful information about the research. It also assesses how the project addressed PCORI’s Methodology Standards. During peer review, experts read a draft report of the research and provide comments about the report. These experts may include a scientist focused on the research topic, a specialist in research methods, a patient or caregiver, and a healthcare professional. These reviewers cannot have conflicts of interest with the study.
The peer reviewers point out where the draft report may need revision. For example, they may suggest ways to improve descriptions of the conduct of the study or to clarify the connection between results and conclusions. Sometimes, awardees revise their draft reports twice or more to address all of the reviewers’ comments.
Peer reviewers commented and the researchers made changes or provided responses. Those comments and responses included the following:
- The reviewers noted that to test the effect of appendicolith status on study outcomes the researchers needed to report on the interaction between the status and the treatment group on the outcomes. In response, the researchers explained that they were not looking at the interaction between appendicolith status and treatment group—they were only interested in the outcomes for patients with an appendicolith because these patients are typically excluded from clinical trials on appendicitis treatment.
- The reviewers questioned the researchers’ approach to their power calculations, which seemed to be focused on differences between treatment groups even though this study was described as a noninferiority comparison. The researchers confirmed that this was a noninferiority study and revised statements in their report to clarify.
- The reviewers asked about the participants who refused randomization and were assigned to a concurrent observational study where participants could choose surgery or medication to treat their appendicitis. The researchers edited the report to clarify that they used inverse probability weighting in the observational sample to account for baseline differences between treatment groups. In addition, the researchers compared the observational cohort after adjusting for baseline differences to the randomized cohort and found similar results for study outcomes.
Conflict of Interest Disclosures
- Has Results