Using Medicaid Data to Improve Childhood Lead Poisoning Prevention Program Outcomes and Blood Lead Surveillance.

CONTEXT: Wisconsin-specific data revealed that not all Medicaid providers were testing children appropriately for blood lead levels and not all blood lead tests were reported to the Department of Health Services, Childhood Lead Poisoning Prevention Program. The Medicaid program requires blood lead screening for all Medicaid-enrolled children at specific ages. Wisconsin state law requires reporting of all blood lead test results. Projects were implemented to encourage appropriate testing for Medicaid-enrolled children and improve blood lead surveillance. METHODS: Medicaid billing data were linked to blood lead data to identify Medicaid-enrolled children who had not received the required tests. Medicaid provider report cards were distributed annually from 2006 to 2011 to inform providers of their compliance with federal testing requirements and of the names of children within their practice who had not been tested. Blood lead tests billed to Medicaid but not in the blood lead database were identified and billing providers were contacted to obtain the test report. RESULTS: The number of children tested increased from 81 834 children per year in 2006 to 106 003 children per year in 2010. Testing of Medicaid-enrolled children increased by 31% from 2006 to 2010. The percentage of Medicaid-enrolled children receiving an age-appropriate test increased from 46% in 2004 to a high of 55% in 2010. There were 9035 blood lead tests identified in the Medicaid billing data that had not been reported from 2007 to 2015. There were 468 billing providers who had unreported tests. All sites with unreported tests were contacted, 84% of test results were obtained, and 14% of test records could not be retrieved. Outpatient clinics accounted for the majority of all unreported tests (72%) and irretrievable test records (74%). DISCUSSION: Childhood lead poisoning prevention programs can effectively utilize Medicaid data to increase testing and improve blood lead surveillance. Primary health care providers should ensure that Medicaid-enrolled children in their care receive the age-appropriate tests. Many Wisconsin health care providers lack awareness of blood lead test reporting requirements. Outpatient clinics account for the largest proportion of unreported tests and highest priority should be given working with these sites to improve reporting practices.

Quantile regression in environmental health: Early life lead exposure and end-of-grade exams.

Conditional means regression, including ordinary least squares (OLS), provides an incomplete picture of exposure-response relationships particularly if the primary interest resides in the tail ends of the distribution of the outcome. Quantile regression (QR) offers an alternative methodological approach in which the influence of independent covariates on the outcome can be specified at any location along the distribution of the outcome. We implemented QR to examine heterogeneity in the influence of early childhood lead exposure on reading and math standardized fourth grade tests. In children from two urban school districts (n=1,076), lead exposure was associated with an 18.00 point decrease (95% CI: -48.72, -3.32) at the 10th quantile of reading scores, and a 7.50 point decrease (95% CI: -15.58, 2.07) at the 90th quantile. Wald tests indicated significant heterogeneity of the coefficients across the distribution of quantiles. Math scores did not show heterogeneity of coefficients, but there was a significant difference in the lead effect at the 10th (ß=-17.00, 95% CI: -32.13, -3.27) versus 90th (ß=-4.50, 95% CI: -10.55, 4.50) quantiles. Our results indicate that lead exposure has a greater effect for children in the lower tail of exam scores, a result that is masked by conditional means approaches.