In the field of CVI professionals, the three main formal CVI assessments include the CVI Range by Dr. Christine Roman Lantzy, the Preverbal Visual Assessment (PREVIAS), and the Visual Assessment Scale (VAS). The categories of visual behaviors contained in assessment questions can vary slightly depending on the assessment being used but are generally comparable to those on the other assessments. Although very similar, each tool also has unique features that set it apart. Here is an overview.
The visual characteristics or behaviors they screen for as well as the primary purpose of each is summarized as follows.
CVI Range
Visual Characteristics:
- Color preference
- Need for movement
- Visual latency
- Visual field preference
- Difficulties wit visual complexity
- Light-gazing
- Difficulty with distance viewing
- Atypical visual reflexes
- Difficulty with visual novelty (newness)
- Absence of visually guided reach
CVI Range Overall Purpose:
To give a picture of student’s current level of functioning and aid in the selection of appropriate supports by placing them in one of three phases focused on progression towards resolution of CVI behaviors.
PREVIAS
Visual Domains:
- Visual attention
- Visual communication
- Visual-motor coordination
- Visual processing
PREVIAS Overall Purpose:
To place infants in or outside of normal visual development parameters and screen for potential CVI in order to prevent later misdiagnosis as the baby grows.
VAS
Characteristics:
- No visual curiosity
- Looking away when reaching for or handling objects
- Short and fleeting visual behavior
- Variable visual behavior
- Inability to use vision simultaneously with other senses
- Looking is tiring
- Familiar gives better visual behavior and recognition
- Prefers auditory over visual stimuli
- Staring into light sources
VAS Overall Purpose:
Diagnostic tool for evaluating the basic visual functioning skills of children and adults with profound intellectual and multiple disabilities (PIMD) so as to give an indication of the direction of intervention for visual rehabilitation.