title: Reliability of voiding cystourethrogram for the grading of vesicoureteral reflux.
abstract: OBJECTIVE
  The voiding cystourethrogram (VCUG) is a commonly employed radiographic test used in the management of vesicoureteral reflux (VUR). Recently, the reliability of VCUG to accurately grade VUR has been questioned. The purpose of this study is to examine reliability of the VCUG for the grading of VUR in a setting mimicking daily practice in a busy pediatric hospital.
  
  
  METHODS
  Two-hundred consecutive VCUGs were independently graded by two pediatric urologists and two pediatric radiologists according to the International Classification of Vesicoureteral Reflux. A weighted kappa coefficient was calculated to determine inter-rater agreement and a modified McNemar test was performed to assess rater bias. Further assessment for impact on clinical and research decision-making was made for disagreement between grades II and III.
  
  
  RESULTS
  Weighted kappa values reflect strong reliability of VCUG for grading VUR between and among urologists and radiologists ranging from 0.95 to 0.97. There was statistically significant bias with radiologists reporting higher grades. Despite high kappa values, disagreement between raters was not infrequent and most common for grades II-IV.
  
  
  CONCLUSIONS
  VCUG is reliable for grading VUR, but small differences in grading between raters were detected and may play an important role in clinical decision-making and research outcomes.
authors.affiliation: Division of Urology, University of Utah, Primary Children's Medical Center, 30 North 1900 East, Salt Lake City, UT 84132, USA. Electronic address: brock.oneil@hsc.utah.edu.
authors.forename: Brock B
authors.initials: BB
authors.lastname: O'Neil
authors.affiliation: Division of Urology, University of Utah, Primary Children's Medical Center, 30 North 1900 East, Salt Lake City, UT 84132, USA.
authors.forename: Patrick C
authors.initials: PC
authors.lastname: Cartwright
authors.affiliation: Department of Medical Imaging, Primary Children's Medical Center, 100 N Mario Capecchi Dr, Salt Lake City, UT 84113, USA.
authors.forename: Constance
authors.initials: C
authors.lastname: Maves
authors.affiliation: Department of Medical Imaging, Primary Children's Medical Center, 100 N Mario Capecchi Dr, Salt Lake City, UT 84113, USA.
authors.forename: Karin
authors.initials: K
authors.lastname: Hoeg
authors.affiliation: Division of Epidemiology, University of Utah, 295 Chipeta Way, Salt Lake City, UT 84108, USA.
authors.forename: Angela P
authors.initials: AP
authors.lastname: Presson
authors.affiliation: Division of Urology, University of Utah, Primary Children's Medical Center, 30 North 1900 East, Salt Lake City, UT 84132, USA.
authors.forename: M Chad
authors.initials: MC
authors.lastname: Wallis
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003950:Diagnostic Techniques, Urological; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D011859:Radiography; D015203:Reproducibility of Results; D014521:Urethra / Q000000981:diagnostic imaging*; D001743:Urinary Bladder / Q000000981:diagnostic imaging*; D014554:Urination; D014718:Vesico-Ureteral Reflux / Q000000981:diagnostic imaging*
keywords: Classification; Radiology; Reproducibility of results; Vesicoureteral reflux
references.citation: Pediatr Nephrol. 1997 Aug;11(4):455-9
references.pmid: 9260245
references.citation: J Bone Joint Surg Am. 2009 May;91 Suppl 3:99-106
references.pmid: 19411507
references.citation: J Urol. 2012 Oct;188(4 Suppl):1608-12
references.pmid: 22910235
references.citation: J Urol. 2010 Sep;184(3):1134-44
references.pmid: 20650499
references.citation: Biometrics. 1977 Mar;33(1):159-74
references.pmid: 843571
references.citation: Pediatrics. 2008 Nov;122(5):1064-71
references.pmid: 18977988
references.citation: Pediatrics. 2006 Mar;117(3):626-32
references.pmid: 16510640
references.citation: AJR Am J Roentgenol. 1989 Oct;153(4):807-10
references.pmid: 2773738
references.citation: Arch Dis Child. 2008 Mar;93(3):229-31
references.pmid: 17626141
references.citation: J Urol. 2012 Oct;188(4 Suppl):1490-2
references.pmid: 22906646
references.citation: AJR Am J Roentgenol. 1999 Mar;172(3):791-3
references.pmid: 10063884
references.citation: J Urol. 2008 Feb;179(2):674-9; discussion 679
references.pmid: 18082208
references.citation: Pediatrics. 2005 Feb;115(2):426-34
references.pmid: 15687452