Assessment tool for visual perception deficits in cerebral visual impairment: reliability and validity

Area of Science:

• Ophthalmology and Vision Science
• Developmental Psychology
• Pediatric Neuro-rehabilitation

Background:

• Accurate assessment of visual impairment in young children is crucial for early intervention.
• Existing tools may not specifically target visual perception deficits related to cerebral visual impairment (CVI).
• The Children's Visual Impairment Test for 3- to 6-year-olds (CVIT 3-6) was developed to address this need.

Purpose of the Study:

• To evaluate the reliability and validity of the Children's Visual Impairment Test for 3- to 6-year-olds (CVIT 3-6).
• To determine if CVIT 3-6 specifically measures visual perception deficits.
• To assess the influence of intellectual abilities and visual acuity on CVIT 3-6 performance.

Main Methods:

• Reliability was assessed using test-retest correlation and intraclass correlation coefficient (ICC) in a validation group (n=59).
• Internal validity was examined via confirmatory factor analysis on a normative sample (n=301).
• External validity was determined by correlating CVIT 3-6 scores with established tests (L94, Beery-VMI, SON-R 2.5-7, SRS) and comparing performance across validation groups (typically developing, CVI, intellectual impairment, simulated impairment).

Main Results:

• The CVIT 3-6 exhibited very good test-retest reliability (r=0.82, ICC=0.80) and confirmed its hypothesized factor structure.
• Strong correlations were found with tests measuring visual perception (L94, SON-R 2.5-7), while weaker correlations were observed with other measures (Beery-VMI, SRS).
• Children with CVI scored significantly lower than other validation groups, indicating specificity for CVI-related deficits.

Conclusions:

• The CVIT 3-6 is a reliable and valid tool for assessing visual perception in 3- to 6-year-olds.
• The test's factor structure aligns with established principles of vision science.
• CVIT 3-6 effectively measures CVI-related visual perception impairments, independent of intellectual abilities or low visual acuity.