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Assessing Geographic Variation in Strabismus Diagnosis among Children Enrolled in Medicaid
Joshua R Ehrlich1, Rebecca Anthopolos2, Joshua Tootoo2
1Department of Ophthalmology and Visual Sciences, University of Michigan Medical School, Ann Arbor, Michigan; Institute for Healthcare Policy and Innovation, University of Michigan, Ann Arbor, Michigan.
Insights
Strabismus diagnosis rates vary significantly by community for children with Medicaid. Poorer communities had lower diagnosis rates, regardless of race, highlighting access disparities in pediatric eye care.
Area of Science:
- Ophthalmology and Public Health
- Pediatric Eye Care Disparities
- Health Services Research
Background:
- Strabismus, a common pediatric eye condition, requires timely diagnosis and treatment for optimal visual development.
- Variations in healthcare access and utilization can lead to disparities in strabismus diagnosis rates among children.
- Understanding community-level factors influencing diagnosis is crucial for addressing pediatric eye health inequities.
Purpose of the Study:
- To investigate geographic and community-level variations in strabismus diagnosis among children enrolled in Medicaid.
- To identify factors associated with the likelihood of receiving a strabismus diagnosis within different communities.
- To highlight potential disparities in access to pediatric eye care services.
Main Methods:
- Retrospective cohort analysis of children aged 10 years or younger enrolled in Medicaid in Michigan and North Carolina in 2009.
- Utilized Medicaid Analytic Extract database and International Classification of Diseases, 9th Revision, Clinical Modification codes for strabismus identification.
- Employed Bayesian hierarchical spatial probit models to analyze strabismus diagnosis risk across communities (ZIP Code Tabulation Areas).
Main Results:
- In 2009, 1.5% of eligible children in Michigan and 1.1% in North Carolina received a strabismus diagnosis.
- Diagnosis rates were lower for Black and Hispanic children compared to White children in both states.
- Children in poorer communities were less likely to be diagnosed with strabismus, independent of race/ethnicity.
Conclusions:
- A child's likelihood of strabismus diagnosis is significantly associated with their residential community's characteristics.
- Findings underscore the importance of equitable access to eye care services and diagnostic professionals, especially in less affluent communities.
- Addressing community-level disparities is essential for improving timely strabismus diagnosis and treatment in children.
Purpose:
To determine how strabismus diagnosis varies within a given community and across communities among children with Medicaid health insurance.
Design:
Retrospective cohort analysis.
Participants:
Children aged ≤10 years enrolled in Medicaid in Michigan or North Carolina during 2009.
Methods:
Children who met the study inclusion criteria were identified from the Medicaid Analytic Extract database, which includes claims data for all children enrolled in Medicaid throughout the United States. Residential location was determined by the last known 5-digit ZIP code for each child, which was linked to the centroid of a ZIP Code Tabulation Area (ZCTA) for geo-referencing and spatial analyses. International Classification of Diseases, 9th Revision, Clinical Modification billing codes were used to identify children diagnosed with strabismus (code 378.xx). Bayesian hierarchical intrinsic conditional autoregressive spatial probit models were used to determine the risk of a child receiving a strabismus diagnosis in communities throughout Michigan and North Carolina. Maps display communities (ZCTAs) where the 95% credible intervals for the spatial random effects estimates do not cross zero, allowing for identification of locations with increased and decreased strabismus diagnosis risk relative to other communities in the states.
Main Outcome Measures:
Likelihood of receiving a diagnosis of strabismus.
Results:
In 2009, among 519 212 eligible children in Michigan, 7535 (1.5%) received ≥1 strabismus diagnosis, and in North Carolina, 5827 of 523 886 eligible children (1.1%) were diagnosed with strabismus. In both states, the proportion receiving a strabismus diagnosis among black (0.9% in Michigan; 0.7% in North Carolina) and Hispanic (1.1% in Michigan; 0.8% in North Carolina) children was lower than the proportion for white children (1.8% in Michigan; 1.6% in North Carolina). Children living in poorer communities in both states were less likely to be diagnosed with strabismus independent of their race/ethnicity.
Conclusions:
A child's likelihood of being diagnosed with strabismus is associated with characteristics of the residential community where he or she resides. The findings of this study highlight the importance of ensuring that children who live in less affluent communities have access to the necessary services and eye care professionals to properly diagnose and treat them for this condition.
