title: The Diagnosis and Management of Patients with Renal Colic across a Sample of US Hospitals: High CT Utilization Despite Low Rates of Admission and Inpatient Urologic Intervention.
abstract: OBJECTIVE
  Symptomatic ureterolithiasis (renal colic) is a common Emergency Department (ED) complaint. Variation in practice surrounding the diagnosis and management of suspected renal colic could have substantial implications for both quality and cost of care as well as patient radiation burden. Previous literature has suggested that CT scanning has increased with no improvements in outcome, owing at least partially to the spontaneous passage of kidney stones in the majority of patients. Concerns about the rising medical radiation burden in the US necessitate scrutiny of current practices and viable alternatives. Our objective was to use data from a diverse sample of US EDs to examine rates of and variation in the use of CT scanning, admission, and inpatient procedures for patients with renal colic and analyze the influence of patient and hospital factors on the diagnostic testing and treatment patterns for patients with suspected renal colic.
  
  
  METHODS
  We conducted a retrospective cohort study of adult patients who received a diagnosis of renal colic via a visit to an ED at 444 US hospitals participating in the Premier Healthcare Alliance database from 2009-2011. We modeled use of CT, admission, and inpatient urologic intervention as functions of both patient characteristics and hospital characteristics.
  
  
  RESULTS
  Over the 2-year period, 307,612 patient visits met inclusion criteria. Among these patients, 254,211 (82.6%) had an abdominal CT scan, with 91.5% being non-contrast ("renal protocol") CT scans. Nineteen percent of visits (58,266) resulted in admission or transfer, and 9.8% of visits (30,239) resulted in a urologic procedure as part of the index visit. On multivariable analysis male patients, Hispanic patients, uninsured patients, and privately insured patients were more likely to have a CT scan performed. Older patients and those covered by Medicare were more likely to be admitted, and once admitted, white patients and privately insured patients were more likely to have a urologic intervention. Only hospital region was associated with variation in CT rates, and this variation was minimal. Region and size of the hospital were associated with admission rates, and hospitals with more practicing urologists had higher intervention rates.
  
  
  CONCLUSIONS
  In this dataset, the majority of patients did not require admission or immediate intervention. Despite this, the large majority received CT scans, in a cohort representing 15-20% of all US ED visits. The CT rate was minimally variable at the hospital level, but the admission rates varied 2-fold, suggesting that hospital-level factors affect patient management. The high rate of CT usage coupled with the low rate of immediate intervention suggests that further research is warranted to identify patients who are at low risk for an immediate intervention, and could potentially be managed with ultrasound alone, expectant management, or delayed CT.
authors.affiliation: Department of Emergency Medicine, Baystate Medical Center, Springfield, Massachusetts, United States of America.|Tufts University School of Medicine, Boston, Massachusetts, United States of America.|Center for Quality of Care Research, Baystate Medical Center, Springfield, Massachusetts, United States of America.
authors.forename: Elizabeth M
authors.identifier: http://orcid.org/0000-0003-3661-4023
authors.initials: EM
authors.lastname: Schoenfeld
authors.affiliation: Center for Quality of Care Research, Baystate Medical Center, Springfield, Massachusetts, United States of America.
authors.forename: Penelope S
authors.initials: PS
authors.lastname: Pekow
authors.affiliation: Center for Quality of Care Research, Baystate Medical Center, Springfield, Massachusetts, United States of America.
authors.forename: Meng-Shiou
authors.initials: MS
authors.lastname: Shieh
authors.affiliation: Duke Clinical Research Institute and Division of Urologic Surgery, Duke University School of Medicine, Durham, North Carolina, United States of America.
authors.forename: Charles D
authors.initials: CD
authors.lastname: Scales
authors.affiliation: Tufts University School of Medicine, Boston, Massachusetts, United States of America.|Center for Quality of Care Research, Baystate Medical Center, Springfield, Massachusetts, United States of America.|Department of Internal Medicine, Baystate Medical Center, Springfield, Massachusetts, United States of America.
authors.forename: Tara
authors.initials: T
authors.lastname: Lagu
authors.affiliation: Tufts University School of Medicine, Boston, Massachusetts, United States of America.|Center for Quality of Care Research, Baystate Medical Center, Springfield, Massachusetts, United States of America.|Department of Internal Medicine, Baystate Medical Center, Springfield, Massachusetts, United States of America.
authors.forename: Peter K
authors.initials: PK
authors.lastname: Lindenauer
mesh_terms: D000328:Adult; D003657:Decision Making; D004635:Emergency Medicine / Q000379:methods; D004636:Emergency Service, Hospital; D005260:Female; D064368:Healthy Volunteers; D006760:Hospitalization; D006801:Humans; D007297:Inpatients; D007669:Kidney Calculi / Q000175:diagnosis / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009398:Nephrology / Q000379:methods; D010343:Patient Admission; D010358:Patient Participation; D056844:Renal Colic / Q000175:diagnosis* / Q000000981:diagnostic imaging*; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000706:statistics & numerical data*; D016896:Treatment Outcome; D014463:Ultrasonography; D014481:United States; D014572:Urology / Q000379:methods*