title: A contribution to situation awareness analysis: understanding how mismatched expectations affect road safety.
abstract: OBJECTIVE
  The aim of the study was to clarify how knowledge elaborated by specific experience may lead to erroneous expectations during interactions between drivers and riders.
  
  
  BACKGROUND
  Situation awareness is partly determined by prior knowledge. Unshared knowledge may cause difficulties in managing driving interactions, but there is still an important gap in the literature devoted to this field of research.
  
  
  METHODS
  There were 226 participants, distinguished according to their vehicle use (for drivers, type of vehicle driven and whether they were exclusive or dual drivers; for motorcycle and scooter riders, the type of powered two-wheeler [PTW] used and its engine size) and their driving experience. Focusing on the most vulnerable users, we studied prior representations to interactions using a series of closed questions on drivers' performance relating to different stages of the interaction process from the perspective both of drivers' self-reflection and of riders' expectations.
  
  
  RESULTS
  Although most drivers are self-confident, their abilities tend to be questioned by riders. Owners of medium or large motorbikes feel that drivers do not assess their approach speed accurately. Similarly, scooter riders doubt drivers' ability to assess the distance that separates them from PTWs. Riders who use medium or large motorbikes are more likely to question drivers' skills in relation to crossing situations. Scooter riders do so more often for overtaking situations.
  
  
  CONCLUSIONS
  The development of shared prior knowledge is essential to prevent accidents and incidents between drivers and riders.
  
  
  CONCLUSIONS
  To help improve effectiveness, we recommend specific ways of embedding each type of road user profile in training, prevention, and research.
authors.affiliation: Université Paris-Est-IFSTTAR (French Institute of Science and Technology for Transport, Development, and Networks), Noisy-le-Grand, France. christophe.munduteguy@ifsttar.fr
authors.forename: Christophe
authors.initials: C
authors.lastname: Mundutéguy
authors.forename: Isabelle
authors.initials: I
authors.lastname: Ragot-Court
mesh_terms: D000063:Accidents, Traffic / Q000517:prevention & control; D000328:Adult; D059031:Anticipation, Psychological; D001334:Automobile Driving / Q000523:psychology*; D001364:Awareness; D006801:Humans; D008297:Male; D011939:Mental Recall; D009049:Motorcycles; D013647:Task Performance and Analysis; D055815:Young Adult