The CVI Range – a Bit of History
The CVI Range was developed over a span of years and was driven by the question, how can I conceptualize degrees of CVI? As early as 1990, I began explaining to parents that I thought of CVI as being along a 0-10 continuum where zero represented little or no functional vision and ten represented normal visual function. I used this explanation when I talked with parents, and I noticed that they seemed interested in changes I reported over time. Then, one day a parent asked me to explain what the numbers meant. That was a threshold moment that began the operationalization of the continuum and, the development of the first version of The CVI Range.
The first iteration was a checklist. It was a single sheet with statements that described the unique behaviors of CVI. In 1994-6, I conducted research at the University of Pittsburgh. The research was used to determine whether a set of parent interview questions could correlate with visual behaviors associated with the characteristics of CVI. They did. In fact, the correlation between the responses parents provided and the behavior of their child was highly significant.
So, by 1996, I had a checklist and a valid interview instrument. With the help of my mentor, Dr. James Jan, I began to refine the structure of The CVI Range. A psychometrician generously offered her talents and by 2000, the essential content of Ratings I & II were in place. Further improvements were put in place prior to the publication of Cortical Visual Impairment: An Approach to Identification, Assessment & Intervention (2007) and further minor changes occurred in preparation for the revision of the textbook in 2018. In 2008, AER honored this foundational work with The C. Warren Bledsoe Award.
The CVI Range will likely undergo one more set of updates. The results of the Ingerman CVI Range Study (Borchert, Roman, 2021-) will be used to hone the test to its most reliable and valid format.
Purposes of The CVI Range
There are a number of purposes associated with The CVI Range.
- It is used to describe a present level of functional vision including a broad Phase (I, II, III) and a set of 2 specific scores (Rating I & Rating II)
- It is used to follow changes in functional vision over time
- It is used to guide accommodations and CVI-specific instructional methods
- It is used to create a CVI Schedule to incorporate the principles of CVI into routines across the learning and living day.
- It is used to measure the impact of each of the CVI characteristics
- It is used to determine whether functional vision is adversely affecting access to education
Value of Obtaining Scores
Application of CVI Range in research and practice