Validation of the brain injury associated visual impairment - impact questionnaire (BIVI-IQ)

• Published in: Quality of life research 2024-03, Vol.33 (3), p.777-791
• Main Authors: Hepworth, L. R., Kirkham, J.J., Perkins, E., Helliwell, B., Howard, C., Liptrot, M., Tawana, S., Wilson, E., Rowe, F. J.
• Format: Article
• Language: English
• Subjects: Medicine; Medicine & Public Health; Public Health; Quality of Life Research; Questionnaires; Rasch model; Sociology; Traumatic brain injury; Validation studies; Validity; Visual impairment
• ISSN: 0962-9343; 1573-2649
• DOI: 10.1007/s11136-023-03565-0

Purpose The Brain Injury associated Visual Impairment - Impact Questionnaire (BIVI-IQ) was developed to assess the impact of post-stroke visual impairment. The development of the questionnaire used robust methods involving stroke survivors and clinicians. The aim of this study was to assess the validity of the BIVI-IQ in a stroke population. Methods Stroke survivors with visual impairment were recruited from stroke units, outpatient clinics and non-healthcare settings. Participants were asked to complete questionnaire sets on three separate occasions; the BIVI-IQ at each visit with additional questionnaires at baseline and visit 2. Vision assessment and anchor questions from participants and clinicians were collected. The analysis included assessment of missing data, acceptability, Rasch model analysis, test–retest reliability, construct validity (NEI VFQ-25, EQ-5D-5L) and responsiveness to change. Results 316 stroke survivors completed at least one questionnaire of the 326 recruited. Mean age was 67 years and 64% were male. Adequate fit statistics to the Rasch model were reached ( χ 2  = 73.12, p  = 0.02) with two items removed and thresholds of two adjusted, indicating validity and unidimensionality. Excellent test–retest reliability was demonstrated (ICC = 0.905) with a 3-month interval. Construct validity was demonstrated with a strong significant correlation to the NEI VFQ-25 ( r  = 0.837, p