Avalere Health has found, in a study of 2015 ACA private plan enrollment data, that healthcare.gov outperformed state exchanges on two measures: retention of 2014 enrollees and enrollment of new customers.
To explain the lower retention in states that ran their own exchanges, Avalere floats the possibility* that those states (all but one of which expanded Medicaid) may have had more churn into Medicaid than states using healthcare.gov (where over 70% of enrollees were in states that refused the Medicaid expansion). I'll cite some evidence below that many states that expanded Medicaid did not have low retention in the private plan market. But I do think that Medicaid enrollment may partly explain the second discrepancy -- why state-based exchanges had lower private-plan enrollment growth in 2015 than states on healthcare.gov.
To explain the lower retention in states that ran their own exchanges, Avalere floats the possibility* that those states (all but one of which expanded Medicaid) may have had more churn into Medicaid than states using healthcare.gov (where over 70% of enrollees were in states that refused the Medicaid expansion). I'll cite some evidence below that many states that expanded Medicaid did not have low retention in the private plan market. But I do think that Medicaid enrollment may partly explain the second discrepancy -- why state-based exchanges had lower private-plan enrollment growth in 2015 than states on healthcare.gov.
