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Psychometric development of Crash Scene Sketch

Crash Scene Sketch – research development

The current form of the Crash Scene Sketch is here.

Strategy: link to the widely used Clock Drawing Test – Drawing tasks have a long history in neurology and neuropsychology.  Clock drawing emerged as one of several drawings in the Boston Diagnostic Aphasia Exam – Non-Aphasia battery in 1972.  In 1994 a whole book devoted to Clock Drawing was published.

 There are numerous scoring approaches, but the one developed by Barbara Freund seems to be most frequently used by Driver Rehabilitation Specialists (DRSs).  She has published an interesting article entitled, “In My Car the brake is on the right,” which associates clock drawing with wrong pedal errors.  

There is an “Executive Clock Drawing Test” which has sub-tests – CLOX1 (drawing) and CLOX2 (copying).  In contrast to copying, drawing requires considerable executive function.  By comparing drawing to copying we can measure executive function, which is central to safe driving. (Indeed, the driver is, in effect, the Chief Executive Officer of the vehicle.)

Extending this approach to the task of sketching out a collision event allows us to assess executive function in a more face valid and, therefore, convincing manner.

Goal:  Establish a psychometric foundation, so that the Crash Scene Sketch can become a test.

  1. Finalizing the text
  2. In the present version, should we indicate that it is a left (right in the UK +) turn? I am inclined to make this change.
  3. Scoring system like Freund did for Clock Drawing
  4. Goal: develop a task that most drivers can do nearly perfectly
  5. Establishing norms for drivers
    1. Age based??  (No, but may wish to have this information)
    2. How do we collect norms because it is not part of our usual work?
    3. Do we need IRB approval?  Which IRB?
    4. Sampling considerations
  6. Establishing reliability
    1. Scorer
    2. Test-re-test
  7. Establishing validity
    1. Concurrent validity, e.g., does it agree with
      1.  Clock Drawing? 
      2. Other tests
    2. Predictive validity –
      1. does it agree with (a) Behind the Wheel (BTW) assessment, (b) future driving, (c) future crash record?
      2. Does it agree with overall recommendation for driving?
      3. Can we identify, based on this, scoring criteria for passing and failing?


  1. ADED involvement
    1. Maybe repeat the ADED-NE seminar and announce in News Brake with a specific structured “ask” to collaborate by
      1. Submitting data both norms and clinical
      2. More active engagement, leading to a material product – along the lines of the Snellgrove Maze – which could at least be published in News Brake.
  2. Without ADED involvement
  3. Would we need external funding?  Sources?