title: Support for external validity of radiological anatomy tests using volumetric images.
abstract: OBJECTIVE
  Radiology practice has become increasingly based on volumetric images (VIs), but tests in medical education still mainly involve two-dimensional (2D) images. We created a novel, digital, VI test and hypothesized that scores on this test would better reflect radiological anatomy skills than scores on a traditional 2D image test. To evaluate external validity we correlated VI and 2D image test scores with anatomy cadaver-based test scores.
  
  
  METHODS
  In 2012, 246 medical students completed one of two comparable versions (A and B) of a digital radiology test, each containing 20 2D image and 20 VI questions. Thirty-three of these participants also took a human cadaver anatomy test. Mean scores and reliabilities of the 2D image and VI subtests were compared and correlated with human cadaver anatomy test scores. Participants received a questionnaire about perceived representativeness and difficulty of the radiology test.
  
  
  RESULTS
  Human cadaver test scores were not correlated with 2D image scores, but significantly correlated with VI scores (r = 0.44, P < .05). Cronbach's α reliability was 0.49 (A) and 0.65 (B) for the 2D image subtests and 0.65 (A) and 0.71 (B) for VI subtests. Mean VI scores (74.4%, standard deviation 2.9) were significantly lower than 2D image scores (83.8%, standard deviation 2.4) in version A (P < .001). VI questions were considered more representative of clinical practice and education than 2D image questions and less difficult (both P < .001).
  
  
  CONCLUSIONS
  VI tests show higher reliability, a significant correlation with human cadaver test scores, and are considered more representative for clinical practice than tests with 2D images.
authors: Department of Radiology, University Medical Center Utrecht, Room E01.132, Heidelberglaan 100, 3508 GA, Utrecht, The Netherlands. Electronic address: C.J.Ravesloot@umcutrecht.nl.
authors: Cécile J
authors: CJ
authors: Ravesloot
authors: Department of Radiology, University Medical Center Utrecht, Room E01.132, Heidelberglaan 100, 3508 GA, Utrecht, The Netherlands.
authors: Anouk
authors: A
authors: van der Gijp
authors: Department of Education, Utrecht University, Utrecht, The Netherlands.
authors: Marieke F
authors: MF
authors: van der Schaaf
authors: Department of Radiology, University Medical Center Utrecht, Room E01.132, Heidelberglaan 100, 3508 GA, Utrecht, The Netherlands.
authors: Josephine C B M
authors: JC
authors: Huige
authors: Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands.
authors: Koen L
authors: KL
authors: Vincken
authors: Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands.
authors: Christian P
authors: CP
authors: Mol
authors: Department of Anatomy, University Medical Center Utrecht, Utrecht, The Netherlands.
authors: Ronald L A W
authors: RL
authors: Bleys
authors: Center for Research and Development of Education, University Medical Center Utrecht, Utrecht, The Netherlands.
authors: Olle T
authors: OT
authors: ten Cate
authors: Department of Radiology, University Medical Center Utrecht, Room E01.132, Heidelberglaan 100, 3508 GA, Utrecht, The Netherlands.
authors: Jan P J
authors: JP
authors: van Schaik
mesh_terms: D002102:Cadaver; D004504:Education, Medical, Undergraduate; D004521:Educational Measurement / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D011871:Radiology / Q000193:education*; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires
keywords: Testing; radiological image interpretation; radiology education; volumetric datasets; volumetric images