Table 2.

Representative case descriptions of potential opportunities for improvement for each Diagnostic Error and Evaluation Research (DEER) taxonomy^* domain of the diagnostic process

Diagnostic process phase where opportunities were identified	Case description	Initial diagnosis	Final diagnosis
History	Toddler with multiple hospitalizations for croup and remote history of intubation was admitted with stridor. Diagnosed with croup and required intensive care. Readmitted with recurrent symptoms. On otolaryngology evaluation found to have tracheal stenosis requiring balloon dilation.	Croup	Tracheal stenosis
Exam	Teenager with frequent emergency department visits for moderate persistent asthma presented with cough, tachypnea, and dyspnea. Initial ED exam noted decreased breath sounds but no wheeze. Diagnosed with acute asthma exacerbation but demonstrated limited improvement with bronchodilators. Readmitted with recurrent symptoms. Found to have symptomatic anemia requiring transfusion. Diagnosed with hyperventilation syndrome.	Mild intermittent asthma with (acute) exacerbation	Anemia and Hyperventilation syndrome
Testing	Small for gestational age neonate admitted for hyperbilirubinemia requiring phototherapy. Admission labs demonstrated marked metabolic acidosis. Readmitted soon after discharge with lethargy. Found to be hypoglycemic, hypothermic, with worsening acidosis. Newborn screen was positive for inborn error of metabolism.	Neonatal Physiologic Jaundice	Methylmalonic acidemia
Hypothesis	School aged child admitted with several weeks of headaches, emesis, and weight loss with remote history of minor head injury. Diagnosed with post-concussive symptoms and viral infection. Readmitted with worsening symptoms and new back pain. Imaging and lab testing demonstrated demyelinating disease.	Viral intestinal infection, unspecified	Anti-myelin oligodendrocyte glycoprotein (MOG) associated inflammatory encephalitis
Consults	Adolescent admitted with fever, periorbital edema, headache, back and abdominal pain. Found to have acute kidney injury and hypertension. Diagnosed with viral syndrome. Readmitted with worsening symptoms. Diagnosed with lymphoproliferative disorder.	Viral infection	Multi-centric Castleman Disease
Monitoring	Infant with multiple admissions for insufficient weight gain admitted with vomiting, inconsolability, and dehydration. Found to have hematochezia and hypocalcemia. Diagnosed with viral gastroenteritis. Readmitted soon after discharge with lethargy and required intensive care due to electrolyte derangements, found to have inflammatory bowel disease (IBD).	Infant malnutrition and Gastroenteritis	Very early onset inflammatory bowel disease (VEO-IBD)

No cases were found to have opportunities for improvement in the Access to Care Phase

^*Schiff GD, Kim S, Abrams R, et al. Diagnosing Diagnosis Errors: Lessons from a Multi-institutional Collaborative Project. In: Henriksen K, Battles JB, Marks ES, Lewin DI, eds. Advances in Patient Safety: From Research to Implementation (Volume 2: Concepts and Methodology). Advances in Patient Safety. Agency for Healthcare Research and Quality (US); 2005. Accessed October 23, 2019. http://www.ncbi.nlm.nih.gov/books/NBK20492