Physician Maintenance of Certification Linked to Decreased Health Care Costs

Bradley M. Gray, PhD American Board of Internal Interview with:
Bradley M. Gray, PhD
American Board of Internal Medicine

Medical Research: What is the background for this study? What are the main findings?

Dr. Gray: The American Board of Internal Medicine (ABIM) is committed to evaluating the impact its physician certification programs, including Maintenance of Certification (MOC). That motivated us to investigate the relationship between the MOC requirement and the practice patterns of internists subject to it.

We looked to see whether the original MOC requirement was associated with health care costs and measures of hospitalizations drawn from Medicare claims. Our primary measure of hospitalizations was Prevention Quality Indicators, which were developed by the Agency for Health Care Research and Quality to measure impacts of primary care. These include such things as hospitalizations for an amputation due to diabetic complications. Our health care cost measure included outpatient and inpatient costs.

To examine these associations, we took advantage of a natural experiment that occurred when one group of general internists who originally certified in 1991 were subject to the MOC requirement by 2001, while another group of internists, who originally certified just two years earlier in 1989, were grandfathered out of this requirement.

In essence we can think of the 1991 required group of internists as a group treated by the effects of MOC and the 1989 grandfathered group as a control group in a natural experiment.

We estimated associations with this requirement by comparing outcomes among Medicare beneficiaries treated by the required group of internists before and after the requirement took effect in 2001.

Also before and after the 2001 requirement, we compared this difference to a similar difference in outcomes for a control group of beneficiaries treated by the grandfathered group of internists. At base line before 2001, these beneficiaries had almost identical characteristics and co-morbidities as the beneficiaries treated by the required group of internists.

We did this to account for the natural increase in hospitalizations and health care costs that occur as beneficiaries age, as well as other important factors that might have been coincident with the MOC requirement.

Medical Research: What are the main findings?

Dr. Gray: We found evidence that the MOC requirement was related to about a 2.5 percent reduction in health care costs — on average $167 per Medicare beneficiary per year.

The requirement was also associated with reduced spending on specialty visits (likely resulting from fewer referrals) and reduced spending on imaging and lab testing.

But we did not find evidence that the MOC requirement resulted in either increases or reductions in Prevention Quality Indicators, our primary measure of hospitalizations.

This is not that surprising since other studies have found that prevention quality indicator hospitalizations are much more sensitive to access to care than quality at the point of care. Our study focused on quality at the point of care, since all patients in our study had access to a physician and had Medicare insurance. Despite this, we still felt it was important to see if changes in practice related to MOC might be large enough to trigger measurable associations with these outcomes.

My take on these finding is that the MOC requirement made internists more knowledgeable which meant that they needed to do less testing to reach a diagnosis and did not need to refer as many patient to specialists. All this and likely other things lead to cost saves without a measurable effect on quality of care. In these times of constrained resources, this is an important finding.

Medical Research: What should clinicians and patients take away from your report?

Dr. Gray: A clear implication of our study is that the MOC requirement had positive effects on the way physicians practice Medicine. Just to frame our results, while a $167, or 2.5 percent, reduction in health care costs may seem small for an individual clinician, at the population level these saving can add up to fairly large reductions in costs. Consider that general internists represent 45 percent of all primary care physicians, and internists treat patients of all ages, and that annual health care costs for Medicare program alone at over $500 billion and total health care spending in the trillions. So even a 0.5 percent saving to just the Medicare program, a fraction of what we found, would mean $25 billion dollars in annual savings.

Medical Research: What recommendations do you have for future research as a result of this study?

Dr. Gray: In this study, we focused on the original MOC requirement that applied to internists who initially certified after 1989. The current MOC program includes additional components and is more continuous than the original program, so additional research is needed to examine how these changes might impact the results we report.

Since the results neither rule out nor support an impact of the MOC requirement on quality outcomes, more research is needed that examines other quality indicators that may be more likely to be affected by MOC. This includes examining evidence-based processes of care and intermediate and long-term outcomes as well as indicators related to patient experience and quality of life.


“Association Between Imposition of a Maintenance of Certification Requirement and Ambulatory Care–Sensitive Hospitalizations and Health Care Costs.”