Another common factor used to determine eligibility is the ability of an applicant to access other types of health insurance coverage (e.g., private/employer-based coverage, Medicaid, etc.). States that have established children's health insurance programs separate from Medicaid often require enrollees to be ineligible for Medicaid before being enrolled into their program. This requirement has been established to maximize the number of uninsured children a state can cover in their program while referring Medicaid-eligible children to the state Medicaid program. Nevertheless, the procedures needed to do this may be administratively burdensome especially if they find very few Medicaid-eligible children. For example, a study conducted by the state of Florida showed that only 0.42% of Florida Healthy Kids' enrollees were actually eligible for the state Medicaid program. Florida does not require Medicaid ineligibility, but Healthy Kids does prevent children currently enrolled in Medicaid from concurrently enrolling by cross-referencing each applicant in the current Medicaid beneficiary database.
Although states may have the ability to cross reference their applicants with a current Medicaid beneficiary list, it is difficult for states to clearly identify enrollees' ability to access private insurance. The intention of this restriction is to prevent families from dropping existing private coverage in order to enroll in a state-subsidized program, an effect identified by states as "substitution". Some states, such as Minnesota, have responded to the issue of substitution by requiring a period of uninsurance, a minimum amount of time in which a person has no access to insurance, before they are eligible to enroll in the state program.