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Income-Based Disparities in a Yearly Dental Visit in United States Adults and Children: Trend Analysis 1997 to 2016
Charlotte W Lewis1, Brian D Johnston2, Helen H Lee3
1Department of Pediatrics, University of Washington School of Medicine (CW Lewis, BD Johnston, and CM McKinney), Seattle, Wash; Seattle Children's (CW Lewis, BD Johnston, and CM McKinney), Seattle, Wash.
Objective:
To determine how income-based disparities in a yearly dental visit (the Healthy People 2020 Leading Health Indicator for Oral Health) changed since legislation to expand dental coverage and to compare disparity trends in children and adults.
Methods:
We analyzed Medical Expenditure Panel Survey 1997 to 2016 to determine yearly dental visit rates for US children and adults by family income. We determined measures of income disparity, including the Slope Index of Inequality and the Relative Index of Inequality and examined trends in yearly dental visit, Slope Index of Inequality, and Relative Index of Inequality using joinpoint regression.
Results:
Income-based disparities, absolute and relative, narrowed over time for children. Steady upward trends in yearly dental visit rates were observed for poor and low-income/poor children and no joinpoint was identified that corresponded to legislation expanding dental care coverage for lower income children. Relative income-based disparities in yearly dental visit rates widened for adults over 20 years. After declining for 14 years, yearly dental visit rate increased for poor adults from 2013 to 2016 suggesting a possible positive effect in adult dental care use trends following enactment of the Affordable Care Act.
Conclusions:
In 1997, US children and adults had similar levels of income-based disparity in yearly dental visits, but by 2016, they differed markedly. Trends in income-based disparities in yearly dental visit rate narrowed for children but widened for adults. There are lessons from the expansion of dental care coverage for children that could be applied to improve access to dental care for adults.
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