title: An image-based method to measure all-terrain vehicle dimensions for engineering safety purposes.
abstract: BACKGROUND
  All-terrain vehicle (ATV) crashes are a serious public health and safety concern. Engineering approaches that address ATV injury prevention are critically needed. Avenues to pursue include evidence-based seat design that decreases risky behaviours, such as carrying passengers and operation of adult-size vehicles by children.
  
  
  OBJECTIVE
  The goal of this study was to create and validate an image-based method to measure ATV seat length and placement.
  
  
  METHODS
  Publicly available ATV images were downloaded. Adobe Photoshop was then used to generate a vertical grid through the centre of the vehicle, to define the grid scale using the manufacturer's reported wheelbase, and to determine seat length and placement relative to the front and rear axles using this scale. Images that yielded a difference greater than 5% between the calculated and the manufacturer's reported ATV lengths were excluded from further analysis.
  
  
  RESULTS
  For the 77 images that met inclusion criteria, the mean±SD for the difference in calculated versus reported vehicle length was 1.8%±1.2%. The Pearson correlation coefficient for comparing image-based seat lengths determined by two independent measurers (20 models) and image-based lengths versus lengths measured at dealerships (12 models) were 0.95 and 0.96, respectively.
  
  
  CONCLUSIONS
  The image-based method provides accurate and reproducible results for determining ATV measurements, including seat length and placement. This method greatly expands the number of ATV models that can be studied, and may be generalisable to other motor vehicle types. These measurements can be used to guide engineering approaches that improve ATV safety design.
authors.affiliation: Department of Emergency Medicine, University of Iowa, , Iowa City, Iowa, USA.
authors.forename: Charles A
authors.initials: CA
authors.lastname: Jennissen
authors.forename: Nathan S
authors.initials: NS
authors.lastname: Miller
authors.forename: Kaiyang
authors.initials: K
authors.lastname: Tang
authors.forename: Gerene M
authors.initials: GM
authors.lastname: Denning
mesh_terms: D000063:Accidents, Traffic / Q000517:prevention & control; D000328:Adult; D017278:Air Bags; D002648:Child; D004867:Equipment Design; D004868:Equipment Failure; D006801:Humans; D015541:Off-Road Motor Vehicles / Q000592:standards*; D012307:Risk Factors; D012449:Safety; D014947:Wounds and Injuries / Q000209:etiology / Q000517:prevention & control*