1. Indiana University Emergency Medicine Residency, Indianapolis, Indiana, USA.
2. Research Institute, Children's Hospital Colorado, Aurora, Colorado, USA.
3. Department of Radiology, Children's Hospital Colorado, University of Colorado School of Medicine, Aurora, Colorado, USA.
4. Department of Pediatrics, Children's Hospital Colorado, University of Colorado School of Medicine, Aurora, Colorado, USA.
5. Department of Biostatistics and Informatics, Colorado School of Public Health, Aurora, Colorado, USA.