Use of and Regional Variation in Initial CT Imaging for Kidney Stones

Published in: Pediatrics, v. 134, no. 5, Nov. 2014, p. 909-915

Posted on RAND.org on November 01, 2014

by Gregory Tasian, Jose E. Pulido, Ron Keren, Andrew W. Dick, Claude Messan Setodji, Janet M. Hanley, Rodger Madison, Christopher S. Saigal

Read More

Access further information on this document at Pediatrics

This article was published outside of RAND. The full text of the article can be found at the link above.

Research Questions

  1. How prevalent is use of computer tomography (CT) as an initial diagnostic for children with kidney stones?
  2. In what regions is CT frequently used in this way?

OBJECTIVE: We sought to determine the prevalence of initial computed tomography (CT) utilization and to identify regions in the United States where CT is highly used as the first imaging study for children with nephrolithiasis. METHODS: We performed a cross-sectional study in 9228 commercially insured children aged 1 to 17 years with nephrolithiasis who underwent diagnostic imaging in the United States between 2003 and 2011. Data were obtained from MarketScan, a commercial insurance claims database of 17 827 229 children in all 50 states. We determined the prevalence of initial CT use, defined as CT alone or CT performed before ultrasound in the emergency department, inpatient unit, or outpatient clinic, and identified regions of high CT utilization by using logistic regression. RESULTS: Sixty-three percent of children underwent initial CT study and 24% had ultrasound performed first. By state, the proportion of children who underwent initial CT ranged from 41% to 79%. Regional variations persisted after adjusting for age, gender, year of presentation, and insurance type. Relative to children living in West South Central states, the highest odds of initial CT utilization were observed for children living in the East South Central US Census division (odds ratio: 1.27; 95% confidence interval: 1.06–1.54). The lowest odds of initial CT were observed for children in the New England states (odds ratio: 0.48; 95% confidence interval: 0.38–0.62). CONCLUSIONS: Use of CT as the initial imaging study for children with nephrolithiasis is highly prevalent and shows extensive regional variability in the United States. Current imaging practices deviate substantially from recently published guidelines that recommend ultrasound as the initial imaging study.

Key Findings

  • CT is frequently used as the initial diagnostic study for children with kidney stones treated at freestanding children's hospitals.
  • CT use varies extensively by region.
  • Current imaging practices deviate substantially from guidelines, which recommend ultrasound as the initial imaging study.

This report is part of the RAND Corporation external publication series. Many RAND studies are published in peer-reviewed scholarly journals, as chapters in commercial books, or as documents published by other organizations.

The RAND Corporation is a nonprofit institution that helps improve policy and decisionmaking through research and analysis. RAND's publications do not necessarily reflect the opinions of its research clients and sponsors.