Patient-Centered Medical Home Implementation and Improved Chronic Disease Quality: A Longitudinal Observational Study

Ann-Marie Rosland, Edwin Wong, Matthew Maciejewski, Donna Zulman, Rebecca Piegari, Stephan Fihn, Karin Nelson


Objective: To examine associations between clinics' extent of patient-centered medical home (PCMH) implementation and improvements in chronic illness care quality.

Data source: Data from 808 Veterans Health Administration (VHA) primary care clinics nationwide implementing the Patient Aligned Care Teams (PACT) PCMH initiative, begun in 2010.

Design: Clinic-level longitudinal observational study of clinics that received training and resources to implement PACT. Clinics varied in the extent they had PACT components in place by 2012.

Data collection: Clinical care quality measures reflecting intermediate outcomes and care processes related to coronary artery disease (CAD), diabetes, and hypertension care were collected by manual chart review at each VHA facility from 2009 to 2013.

Findings: In adjusted models containing 808 clinics, the 77 clinics with the most PACT components in place had significantly larger improvements in five of seven chronic disease intermediate outcome measures (e.g., BP < 160/100 in diabetes), ranging from 1.3 percent to 5.2 percent of the patient population meeting measures, and two of eight process measures (HbA1c measurement, LDL measurement in CAD) than the 69 clinics with the least PACT components. Clinics with moderate levels of PACT components showed few significantly larger improvements than the lowest PACT clinics.

Conclusions: Veterans Health Administration primary care clinics with the most PCMH components in place in 2012 had greater improvements in several chronic disease quality measures in 2009-2013 than the lowest PCMH clinics.

This article was featured in the October 25, 2022, Lunch and Learn discussion


  • This study was done as part of the VA healthcare system’s national evaluation of its Patient Centered Medical Home rollout
  • The Veterans’ Healthcare System is the largest integrated US health care system. At the time of the study, over 7 million primary care patients were enrolled in the VA, and over 16 million primary care encounters were recorded


  • Research Question: Did VHA primary care clinics with more extensive PCMH implementation have more improvement in chronic disease quality measures?
  • Clinics with Patient Aligned Care Teams (PACT) in place by 2012 had significantly larger improvements in more than half of the chronic disease quality measures examined than clinics with the least PACT implementation. If you spread these changes out over 10 million patients, in the VA about 30% have diabetes, a 1% change corresponds to about 300,000 people with diabetes, newly meeting a quality metric
  • Dr. Rosland mentioned a recently published study that found integrated mental health services improved physical health outcomes. Leung LB, Rubenstein LV, Jaske E, et al. Association of Integrated Mental Health Services with Physical Health Quality Among VA Primary Care Patients. J Gen Intern Med. 2022;37(13):3331-3337. doi:10.1007/s11606-021-07287-2
  • Health systems that invest resources in PCMH and integrated mental health care delivery across all patients could realize downstream improvements in chronic disease quality measures

Ann O’Malley Reaction

  • CPC+ is the largest multi-payer medical home model in the US to date. Its goal is to support primary care through enhanced payments, support to practices, and care delivery requirements to enhance access, continuity, coordination, comprehensiveness, care management and population health practices. It's a five year long model, with CMS, commercial payers, and Medicaid.
  • Over the first four years of the model there were small improvements in some clinical quality metrics. For example, we found increases in Medicare beneficiaries who received all recommended services for diabetes. In females, we saw increases in breast cancer screening.

Discussion Summary

  • Measuring and quantifying the degrees to which practices implement these multifaceted primary care medical home models is tricky. How should we measure primary care quality going forward?
  • There was a discussion about how patients were involved in the PCMH implementation.
  • There was a discussion about how patient centered medical homes prepared practices for the COVID-19 pandemic.
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