Health Policy$ense

Sizing Narrow Networks

Analysis of the Breadth of Physician Networks Across All 2014 Silver Plans

There’s been a lot of talk about "narrow" networks in ACA plans, which trade off limited provider coverage for lower premiums. Using a new integrated dataset of physician networks in plans on the federal and state marketplaces, our latest LDI/RWJF Data Brief describes the breadth of physician networks across all silver plans sold in 2014. Using consumer-friendly “t-shirt” sizing, we find that more than 40% of networks can be considered small or x-small, including 55% of networks in HMOs and 25% of PPO networks.

This is the first attempt to help consumers understand the size of the networks they’re buying into. We used publicly available provider directories to gather data on 355 networks offered by 251 issuers in all 50 states and DC. It took a multi-stage cleaning process to standardize and integrate these lists into our dataset, which contains more than 450,000 physicians participating in at least one network, and another dataset with 199,000 non-participating physicians.

We estimated network size based on the fraction of office-based physicians participating in rating areas within a state. We categorized network size into five groups using arbitrary cutoffs that might provide meaningful information to consumers: x-small (less than 10%), small (10%-25%), medium (25%-40%), large (40%-60%), and x-large (more than 60%). The distribution of sizes, overall and by plan type, is shown below:

Chart 1

A consumer might be interested in whether the participation of certain physician specialties was more limited than others. Networks can also be sized by specialty; we found that 36% of primary care networks were small or x-small, compared to 23% of internal medicine subspecialty networks and 59% of oncology networks.

Chart 2

Even more useful to a consumer might be sizing a network within a certain distance, rather than over a state or large rating area. To illustrate, we looked at physician participation rates in the Atlanta, Georgia area, and found that the same network widens or narrows depending on the geographic area chosen:

Chart 3

Intrigued by these data? In the coming months, we plan to make this dataset available to researchers and the public. Researchers, under data use restrictions, will be able to access raw provider data to discover the underlying cost-quality tradeoff, as well as the actual value provided across various plan options. The public dataset will provide policymakers and regulators with detailed information on network size overall, and by specialty.

These data will be meaningful as states implement standards to assure network adequacy. The ACA requires networks to have sufficient numbers and types of providers to deliver services without “unreasonable delay,” though it is left to the states to define what unreasonable means. According to the Commonwealth Fund, states vary in the standards they set based on maximum travel times, appointment wait times, provider-to-enrollee ratios, or extended hours required. New federal rules for 2016 will require plans to publish up-to-date, accurate, and complete provider directories, including information on which providers are accepting new patients, the provider's location, contact information, specialty, medical group, and institutional affiliations. Integrating and standardizing this information into a “Find a Doctor” database comparing network size between plans would far surpass the utility of these online directories.

You can read our Data Brief here.