The Impact of the Medicaid Reimbursement Bump on Influenza Vaccination Rates Among US Teens: Evidence from the National Immunization Survey–Teen 2011–2020

Notes. ^aModels adjusted for age (continuous), sex, race/ethnicity, poverty status, mother’s age, mother’s marital status, type of vaccination facility, number of doctor visits in the past year, Medicaid managed care penetration rates (continuous), and state expansion status. Estimates were also weighted using sampling weights and include individual-level random effects. *P < .05.

↵Notes. ^aPer Table 1 in Centers for Medicare & Medicaid Final rule.¹⁹

↵b Information obtained from Medicaid State Plan Amendment (SPA), attachment 4.19-B for each state accessed at medicaid.gov/medicaid/medicaid-state-plan-amendments. For reimbursement frequency, a state could have chosen to adjust its reimbursement schedule to make payment as the service was provided (FFS) or reimbursed a supplemental amount equal to the difference between the Medicaid rate in effect on July 1, 2009 and the minimum payment required either a monthly or quarterly interval. For vaccine administration reimbursement method, a state could have opted to reimburse at the VFC regional maximum or the Medicare reimbursement level.

Notes. ^aThere were missing responses for number of visits to doctors in the past year.

Notes. ^aAn unified reimbursement change category and reimbursement duration was a compiled from information for CPT codes 90460 and 90471 (see Appendix Table 4). We stratified states with smaller reimbursement increases for both CPT codes as smaller reimbursement change states. States with larger increases that extended the reimbursement bump into 2019 for both CPT codes were classified as larger extended reimbursement states. All other states were categorized as temporary reimbursement states.

↵Notes. ^a Adjusted multivariable regression model also includes adjustment for Medicaid vaccination reimbursements (in US$), state fixed effects for states with reliable data (CO, CT, IA, ID, MA, MI, MN, MO, MS, MT, NH, NM, NV, OK, SC, TX, VT, WY). Medicaid Managed Care penetration rates for children in comprehensive Medicaid plans in states with reliable data were obtained from Medicaid and CHIP Payment and Access Commission (MACPAC) reports.³⁰ Medicaid expansion status was determined by whether a state expanded Medicaid in each year between 2014-2019. The models also included state fixed effects (dummy variable for each state) and a random effect at the person level.

↵a Adjusted multivariable regression model also includes adjustment for Medicaid vaccination reimbursements (in US$), state fixed effects for states with reliable data (CO, CT, IA, ID, MA, MI, MN, MO, MS, MT, NH, NM, NV, OK, SC, TX, VT, WY). Medicaid Managed Care penetration rates for children in comprehensive Medicaid plans in states with reliable data were obtained from Medicaid and CHIP Payment and Access Commission (MACPAC) reports.³⁰ Medicaid expansion status was determined by whether a state expanded Medicaid in each year between 2014 and 2019. The models also included state fixed effects (dummy variable for each state) and a random effect at the person level.

^aModels adjusted for age (continuous), sex, race/ethnicity, poverty status, mother’s age, mother’s marital status, type of vaccination facility, number of doctor visits in the past year, Medicaid managed care penetration rates (continuous), and state expansion status. Estimates were also weighted using sampling weights and include individual-level random effects.