Association Between Specialist Office Visits and Health Expenditures in Accountable Care Organizations | Health Care Delivery Models | JAMA Network Open | JAMA Network
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    1 Comment for this article
    Equitable Available
    Paul Nelson, M.D., M.S. | Family Health Care, P.C. retired
    Any consideration for the participation by primary health care within health care reform must follow the admonition by Eleanor Roosevelt:  "It's better for everybody when it gets better for everybody." In short, our nation's health care reform strategy does not include provisions for a nationally sanctioned, state by state guided, and locally managed process to assure that primary health care is equitably available to every citizen, zip code by zip code, as adjusted for population density and poverty, community by community.

    Furthermore, the federal distribution of funding for post-graduate medical education must be adjusted, not by research
    economic activities alone, but also by an evaluation of state by state needs for primary physician availability.

    When you are not sure whether or not you are improving, it's always best to be sure that you are taking care of the basics. Primary health care should be -- at least -- equitably available, ecologically accessible, justly efficient and reliably effective for every citizen, community by community.
    Original Investigation
    Health Policy
    July 10, 2019

    Association Between Specialist Office Visits and Health Expenditures in Accountable Care Organizations

    Author Affiliations
    • 1Department of Health Policy and Promotion, University of Massachusetts Amherst, Amherst
    JAMA Netw Open. 2019;2(7):e196796. doi:10.1001/jamanetworkopen.2019.6796
    Key Points español 中文 (chinese)

    Question  What is the association between office visits conducted by specialists and health care spending in an accountable care organization?

    Findings  In this cross-sectional study of 620 distinct accountable care organizations, organizations in which 40% to 45% of patient visits were provided by specialists had statistically significantly lower per-beneficiary person-year spending compared with those in which less than 35% or at least 60% of the visits were conducted by specialists.

    Meaning  Some specialist involvement in care processes for patients appears to be necessary for accountable care organizations to lower their costs.


    Importance  Accountable care organizations (ACOs) aim to control health expenditures while improving quality of care. Primary care has been emphasized as a means to reduce spending, but little is known about the implications of using specialists for achieving this ACO objective.

    Objective  To examine the association between ACO-beneficiary office visits conducted by specialists and the cost and utilization outcomes of those visits.

    Design, Setting, and Participants  This cross-sectional study obtained data on 620 distinct ACOs from the Centers for Medicare & Medicaid Services Shared Savings Program Accountable Care Organizations Public-Use Files from April 1, 2012, to September 30, 2017. Generalized estimating equation models were used for analysis of ACOs, adjusting for ACO-beneficiary health status, Medicare enrollment groups, ACO size, and proportion of participating specialists.

    Exposures  Specialist encounter proportion, the percentage of office visits provided by a specialist, was categorized into 7 discrete groups: less than 35%, 35% to less than 40%, 40% to less than 45% (reference group), 45% to less than 50%, 50% to less than 55%, 55% to less than 60%, and 60% or greater.

    Main Outcomes and Measures  The primary outcome was total expenditures (given in US dollars) per assigned beneficiary person-year. The secondary outcomes were total numbers of emergency department visits, hospital discharges, skilled nursing facility discharges, and magnetic resonance imaging orders.

    Results  In total, the data set included 1836 ACO-year (number of participation years per ACO) observations for 620 distinct ACOs. Those ACOs with a specialist encounter proportion of 40% to less than 45% had $1129 (95% CI, $445-$1814) lower per-beneficiary person-year spending than did ACOs in the lowest specialist encounter proportion group and had $752 (95% CI, $115-$1389) lower per-beneficiary person-year spending compared with ACOs in the highest specialist encounter proportion group. Monotonic decreases in emergency department visits, hospital discharges, and skilled nursing facility discharges were observed with increasing specialist encounter proportion. Conversely, monotonic increases in magnetic resonance imaging volume discharges were observed with increasing specialist encounter proportion.

    Conclusions and Relevance  These findings suggest that an ACO’s ability to reduce spending may require sufficient involvement in care processes from specialists, who seem to complement the intrinsic primary care approach in ACOs.