Patients under the care of general internists who score in the top quartile of the American Board of Internal Medicine’s (ABIM) Longitudinal Knowledge Assessment (LKA®) are nearly 8% less likely to receive low-value healthcare services than those treated by lower-scoring physicians, according to a study published in JAMA Internal Medicine. These findings, based on data from 900,000 Medicare beneficiaries, suggest that higher clinician knowledge is directly associated with a reduction in unnecessary tests and interventions, which cost the U.S. healthcare system an estimated $100 billion annually.
Performance Gaps and the Cost of Unnecessary Care
The study, authored by researchers including Jonathan L. Vandergrift of the ABIM, analyzed 7,089 outpatient general internists. It identified a clear performance gap: 28.6% of patients with top-tier physicians received low-value services, compared to 31% of patients under the care of physicians in the bottom performance quartile. The researchers define these low-value services as tests or treatments that provide little to no clinical benefit, such as routine vitamin D testing, head imaging for uncomplicated headaches, and carotid artery disease screening for asymptomatic patients.
Did you know?
If all general internists performed at the level of the top-scoring LKA participants, an estimated 80,000 fewer Medicare fee-for-service beneficiaries would be exposed to low-value medical services each year.
Drivers of Low-Value Testing
The reduction in low-value care was most pronounced in specific diagnostic areas. Patients of high-scoring physicians saw a 16% lower likelihood of undergoing unnecessary diagnostic or preventive testing, an 11% lower likelihood of unnecessary cancer screenings, and a 4% reduction in non-essential imaging. The study highlights two primary drivers of these costs: triiodothyronine (T3) testing for patients with hypothyroidism and prostate-specific antigen (PSA) screening for men aged 75 and older.
According to the authors, PSA testing in older populations is particularly problematic because it often triggers a “cascade” of invasive and expensive follow-up procedures despite rarely leading to actionable findings. While the LKA assessment—which asks 30 questions per quarter over a five-year cycle—appears to correlate with better decision-making, the study notes that even high-scoring physicians still order low-value services for roughly 30% of their patients. This indicates that knowledge is a significant lever, but not the only factor driving clinical behavior.
Future Trends in Physician Certification
The ABIM’s LKA pathway, launched in 2022, serves as an alternative to the traditional one-day, proctored examination. With over 92,000 physicians currently enrolled, the platform provides clinicians with immediate explanations and journal citations after each question. Senior author Bradley Gray, Ph.D., notes that this rigorous assessment provides a “powerful lever” for reducing systemic waste.
Looking ahead, researchers intend to study whether physicians who increase their LKA scores over time subsequently reduce their reliance on low-value services. Future longitudinal studies will examine the full five-year cycle of the LKA to determine if continuous learning leads to sustained improvements in clinical practice and further reductions in healthcare spending.
Frequently Asked Questions
- What is the LKA? The Longitudinal Knowledge Assessment is a flexible, multi-year testing pathway for ABIM-certified physicians that uses quarterly questions to reinforce clinical knowledge.
- What are “low-value services”? These are medical tests or treatments, such as unnecessary PSA screenings or vitamin D tests, that offer little clinical benefit and contribute to the $100 billion in annual waste in the U.S. healthcare system.
- Does higher knowledge guarantee better outcomes? While the study shows an association between high LKA scores and lower use of low-value care, researchers emphasize that systemic factors and policy also play a role in reducing unnecessary costs.
Pro Tip: Physicians can review the specific list of 25 low-value services identified in the JAMA Internal Medicine study to audit their own ordering patterns and align with current clinical guidelines.
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