The main disadvantage of Medicare Advantage from a beneficiary perspective is probably that the wide-open provider choice of traditional Medicare is restricted, at least in HMO-style designs. This could limit access or quality, but there isn’t any research suggesting this is actually the case. More concerns have been raised as some MA plans market “narrow” network designs, which further limit provider choice or provide much richer benefits for a more select group of providers. Research in Health Affairs looks at how prevalent these designs have actually become and in particular what their effect on primary care access might be. (HA Article) MA plan provider directories have many errors, so the researchers used Part D drug data to infer the size of primary care networks. They looked at years 2011 to 2015 to see if there was a change in the number of narrow network plans over time, and in the number of beneficiaries covered by such plans. They looked at networks for MA plans available to individuals, not those marketed to employer retiree groups, and they didn’t include special needs plans. They defined the breadth of a network by assessing the percent of physicians in a county service area that were included.
A narrow network plan was one with less than 30% of the county’s primary care doctors; a medium breadth network had 30% to 69% and a broad network had 70% or more of primary care physicians. Due to sample size issues, only MA plans with a relatively significant membership ended up being included. This may understate the use of narrow networks, as those plans might have smaller enrollment, since they would primarily appeal to people who already had a relationship with the physicians in the network. Narrow network plans were rare throughout the study period; comprising 2.7% of the market in 2011 and only 1.8% in 2015. Broad network plans made up 80.1% of all plans in 2011 and 82.5% in 2015. A number of plans that had a narrow network in an earlier year, broadened it by later years, while broad network plans basically never narrowed their network. In 2011 broad network plans 54% of enrollment, but that rose to 64% by 2015. Narrow network plans tended to occur in urban and wealthier areas and in areas with more doctors. More competition tended to be associated with more narrow network plans. In general, the study does not support concerns that Medicare Advantage plans have narrow networks that might affect access or quality.