Results Summary

What was the research about?

Appendicitis occurs when the appendix, a small part of the intestine, gets infected. Without treatment, the appendix can burst, and infection can spread. Two ways to treat appendicitis are surgery and antibiotics. Surgery removes the appendix, and patients have no chance of getting appendicitis again. But it may take one or two weeks to get better. Antibiotics may work to treat the infection. But if the infection comes back, patients may need surgery later.

In this study, the research team looked at how many children with appendicitis who took antibiotics did not need surgery within one year. They also compared children’s quality of life and how many days of activities they missed when treated with antibiotics or surgery.

What were the results?

One year after they went to the hospital,

  • 67 percent of children who took antibiotics hadn’t needed surgery.
  • On average, children who took antibiotics missed 7 days of activities; children who had surgery missed 11 days.
  • Quality of life was not different between the two groups after one year. But children who took antibiotics had better quality of life one month after they left the hospital.

Who was in the study?

The study included 1,068 children ages 7–17. They received treatment for appendicitis at one of 10 children’s hospitals in the Midwest. Of these children, 83 percent were White, 7 percent were Black, and 11 percent were another race; 10 percent were Latino. The average age was 12, and 62 percent were boys.

What did the research team do?

A doctor from the research team met with children and their caregivers in the hospital to talk about the two treatments; 370 chose antibiotics and 698 chose surgery. Children treated with antibiotics got them by IV at the hospital for at least 24 hours. They also took antibiotics for six days after they got home. Children treated with surgery had surgery within 12 hours. They got IV antibiotics before surgery to prevent infection from the surgery but not to treat appendicitis. They didn’t take antibiotics after surgery.

Children and caregivers filled out surveys when leaving the hospital and one month, six months, and one year later. Surveys asked about quality of life and how many days of activities children missed after treatment. The research team looked at health records to see how many children treated with antibiotics had surgery later.

Patients, caregivers, nurses, doctors, patient educators, and health insurers helped with the study.

What were the limits of the study?

At one year, the research team could contact about three-quarters of children and caregivers. Children and caregivers chose treatment instead of treatment being assigned by chance. Children were from one area of the country, and most were White. Results may differ if more people filled out all the surveys, researchers assigned treatments by chance, or children had diverse backgrounds.

Future research could look at antibiotic treatment and surgery in a diverse group of children. Researchers could also study the results of treatment for a longer time.

How can people use the results?

Doctors, patients, and caregivers can use these results when choosing treatment for children with appendicitis.

Final Research Report

View this project's final research report.

Journal Citations

Article Highlight: More than 70,000 children in the United States have surgery each year to treat appendicitis. As reported in JAMA, a PCORI-funded study found that among children with uncomplicated appendicitis, nonsurgical treatment with antibiotics was successful in more than half of those patients, and compared with surgery initiated shortly after hospital admission, was associated with significantly fewer disability days. However, the results after one year did not meet the threshold success rate specified at the outset of the study.

Peer-Review Summary

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 expressed concern about the inconsistent acceptable threshold for establishing the efficacy of nonsurgical treatment; at one point in the report the researchers indicated that the threshold would be a 70 percent success rate for nonsurgical treatment, but in their conclusions the researchers wrote that nonsurgical treatment should be offered when the success rate was more than 50 percent. The researchers explained that in the absence of prior research establishing an acceptable threshold, they used the 70 percent success rate to interest surgeons in study participation. The researchers changed the conclusions to say that the data do not support a success rate that exceeds the preset 70 percent threshold.
  • The reviewers questioned the report’s description of success and failure at the one-year follow-up point in the study. The reviewers could not identify whether the researchers had included recurrent appendicitis within one year as part of the failure group even though it was more likely that an appendectomy between initial hospitalization and one year postdischarge was caused by recurrent appendicitis rather than the initial condition. The researchers confirmed that their definition of failure of nonoperative treatment at one year included initial in-hospital failures and suspected recurrent appendicitis. The researchers also added data to the report on negative appendectomy rate, which came from not identifying appendicitis at surgery by histology.
  • The reviewers noted that there was an unexpectedly high rate of loss to follow-up in the study and asked for what might explain this and whether the high rate of dropping out posed a risk for selection bias that might have affected the outcomes. The researchers said the high dropout rate may reflect the fact that appendicitis tends to be a time-limited disease and families participating in the study may have lost interest in participating further once the condition resolved. The researchers acknowledged that the high dropout rate could have introduced selection bias but said they believed the bias would equally affect both arms of the study.
  • A reviewer questioned whether it was necessary to have a nonrandomized trial design and asked the researchers to justify conducting a patient-choice trial in this population. The researchers acknowledged that other groups have performed randomized controlled trials even with patients who have treatment preferences, but said that in studies of children with appendicitis, less than 40 percent of eligible patients enrolled and those who enrolled disproportionately represented those who preferred a nonsurgical intervention, which was not offered outside the trial setting. The researchers felt that their pragmatic study design enrolled a broader population than otherwise would have participated and therefore leads to more useful estimates of the effectiveness of nonsurgical versus surgical treatment of appendicitis.

Conflict of Interest Disclosures

Project Information

Peter C. Minneci, MD, MHSc
The Research Institute at Nationwide Children's Hospital
Comparing the Effectiveness of Treating Pediatric Appendicitis with Antibiotics Versus Surgery

Key Dates

April 2016
February 2021

Study Registration Information


Has Results
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Populations Populations PCORI is interested in research that seeks to better understand how different clinical and health system options work for different people. These populations are frequently studied in our portfolio or identified as being of interest by our stakeholders. View Glossary
Intervention Strategy Intervention Strategies PCORI funds comparative clinical effectiveness research (CER) studies that compare two or more options or approaches to health care, or that compare different ways of delivering or receiving care. View Glossary
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Last updated: March 14, 2024