Identifying Individuals with visual impairment in danish healthcare registries
Year: 2026
Type: article
Study design: Observational Study
Abstract: • Question : What criteria can be used to identify individuals with severe visual impairment or blindness (SVI/B) in Danish health registries? • Findings : In this cross-sectional study, we used a capture-recapture method and found that combining data from the Danish Association of the Blind (DAB) and the National Patient Register (NPR) only identifies about 40 % of people living with SVI/B, estimating that the total prevalence of SVI/B in Denmark is approximately 0.32%. • Meaning : The findings of this study indicate that integrating datasets from DAB and NPR provides the most comprehensive cohort for subsequent research. The prevalence of severe binocular visual impairment or blindness (SVI/B) in Denmark has been estimated at approximately 0.2% (12,500 individuals), although the exact number remains uncertain. While international studies have linked blindness to health disparities and reduced quality of life, this has not been thoroughly examined in the Danish context. The aim of this study was to establish a pragmatic registry-based approach for identifying individuals with SVI/B in Danish health registries, thereby enabling future research on health disparities among this population. Register-based cross-sectional study. Individuals with SVI/B identified through the Danish Association of the Blind (DAB) and patients with relevant ICD-codes in the National Patient Register (NPR). Data from NPR and DAB were linked using the unique civil registration number (CPR). Capture-recapture analysis was applied to estimate the total population with SVI/B in Denmark. Among DAB members, 86.4% had eye-related diagnoses recorded in NPR, whereas only 8.6% had diagnostic codes specifically indicating SVI/B. Using NPR data alone, a higher prevalence of individuals with comparable diagnoses was identified. Capture-recapture analysis estimated that 0.32% of the Danish population lives with SVI/B. Neither DAB nor NPR alone captured the entire population of individuals with SVI/B in Denmark, suggesting potential undercounting. However, when combined, these data sources provided a more comprehensive cohort for registry-based research on health and social disparities among individuals living with SVI/B.
Source: AJO International
Authors: Katrine Prisak Jakobsen, Linda Juel Ahrenfeldt, Jakob Grauslund, Lonny Stokholm, Sören Möller
Institutions: University of Southern Denmark, Odense University Hospital
Language: English
Subfield: Epidemiology
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $1,850
Funder: Danmarks Frie Forskningsfond
OpenAlex ID: W7131789367
