BACKGROUND: Diagnostic stewardship is the effort to optimize diagnostic testing to reduce errors while avoiding overtesting and overtreatment. Abdominal pain and appendicitis in children are essential use cases. Delayed diagnosis of appendicitis can be dangerous and even life-threatening, but overtesting is harmful. METHODS: We conducted a retrospective cohort study of children aged 5-17 years presenting with abdominal pain to 26 EDs within the Michigan Emergency Department Improvement Collaborative (MEDIC) from May 1, 2016, to February 29, 2024. We defined two outcome measures summarized by ED. First, we describe the cross-sectional imaging:appendicitis visits ratio, defined as the count of ED visits resulting in any cross-sectional imaging (CT or MRI) divided by the count of ED visits with a diagnosis of appendicitis. Second, we describe the delayed diagnosis rate, defined by an ED visit for abdominal pain resulting in a discharge and subsequent return visit with a diagnosis of appendicitis within 7 days. RESULTS: The sample included 120,112 pediatric visits for abdominal pain at 26 EDs
4967 (4.1%) were diagnosed with appendicitis. The cross-sectional imaging:appendicitis visits ratio varied by site, from as low as 0.2 (95% confidence interval [CI] 0.1-0.2) at a pediatric site to as high as 7.9 (95% CI 4.8-16.4) at an urban ED. The proportion of pediatric ED visits for abdominal pain that resulted in an identified delayed diagnosis of appendicitis was 0.1% (141/120,112). All but four sites had fewer than 10 cases of delayed diagnosis across the study period. CONCLUSIONS: In this retrospective cohort study of 120,000+ ED visits for pediatric abdominal pain, we found that the ratio of visits with cross-sectional imaging to diagnosed cases of appendicitis varied widely across EDs. Delayed diagnosis of appendicitis was uncommon. Adherence to best practices and improved imaging quality may hold promise to improve diagnostic stewardship for children with abdominal pain across EDs.