The Healthcare Effectiveness Data and Information Set (HEDIS) is a set of standardized performance measures that allows consumers and purchasers to reliably compare health plans.1 HEDIS was established by the National Committee for Quality Assurance (NCQA), a health care accreditor that aims to establish scientifically supported health care, to study how well health plans and doctors implement such research-based care and to identify organizations that make patient care better.2 NCQA partners with the Centers for Medicare & Medicaid Services (CMS) to use HEDIS to allow Medicaid, Medicare and commercial health plans to compare their performance and quality of care with other health plans.3 Specifically, NCQA and CMS use HEDIS measures to evaluate Medicare Advantage (MA) plans, which are Medicare health plans offered by private companies including health maintenance organizations (HMOs), preferred provider organizations (PPOs), private fee-for-service plans, Special Needs Plans (SNPs) for individuals with disabling conditions and Medicare Medical Savings Account (MSA) plans.4 HEDIS provides a standard way to compare health care plans across the board, ranging from the various types of Medicare Advantage plans to state-wide Medicaid plans to private commercial health plans.3
According to NCQA, HEDIS includes more than 90 measures across six domains: Effectiveness of Care, Access/Availability of Care, Experience of Care, Utilization and Risk Adjusted Utilization, Health Plan Descriptive Information and Measures Collected Using Electronic Clinical Data Systems.5 Some examples of HEDIS measures include childhood immunization status, emergency department utilization and identification of alcohol and other drug services.6 For most of these measures, the percentage of plans (separated into commercial, Medicare and Medicaid) that submit data to NCQA are listed yearly on the NCQA website.6,7 Given that more than 190 million people are enrolled in health plans that report data using HEDIS,2 consumers can benefit from NCQA’s online transparency.
Due to their ubiquity, HEDIS measures can be used not only by health professionals, health plan administrators and consumers, but also by researchers. For example, a recent study by Hechter et al. used HEDIS measures of treatment initiation and engagement to compare alcohol and other drugs (AOD) use disorder in patients with or without human immunodeficiency virus (HIV).8 Another study by Mosen et al. compared patients who receive dental care to those who do not by using HEDIS measures.9 Meanwhile, Ng-Mak and Rajagopalan used HEDIS measures, such as those for cardiovascular and diabetes screening, to examine quality of care received by individuals with severe mental illness.10 Clearly, researchers use HEDIS measures to evaluate patients and their outcomes.
Nevertheless, it is unclear if HEDIS measures are accurate indicators of quality of patient care and patient outcomes. For example, Harman et al. linked a plan’s HEDIS performance to changes in enrollee health, finding that improved quality of diabetes care can result in better patient health.11 However, Harris et al. found that specification validity (i.e., the ability of a measure to adequately capture care processes and patients) of HEDIS measures was excellent for records from residential and outpatient addiction programs, but more modest and highly variable across non-addiction settings.12 Additionally, one study by Crans Yoon et al. found that compliance with the HEDIS Medication Management for people with Asthma (MMA) measure was not related to improvement in asthma outcomes.13 Thus, though the use of HEDIS measures in research is widespread, it remains to be seen if they can precisely or accurately depict patient outcomes in diverse settings.
Overall, HEDIS provides a standardized way for consumers, health professionals and researchers to compare performance across commercial, Medicare and Medicaid health plans. Given the popularity of HEDIS measures, future research should explore the association between compliance on HEDIS measures and real-life quality of care and patient outcomes across a variety of specialties.
1. Centers for Medicare & Medicaid Services. Healthcare Effectiveness Data and Information Set (HEDIS). July 2017; https://www.cms.gov/Medicare/Health-Plans/SpecialNeedsPlans/SNP-HEDIS.html#targetText=NCQA%20established%20Healthcare%20Effectiveness%20Data,comparison%20of%20health%20plan%20performance.
2. National Committee for Quality Assurance. About NCQA: Learn more about the National Committee for Quality Assurance (NCQA). 2019; https://www.ncqa.org/about-ncqa/.
3. Beaton T. How HEDIS, CMS Star Ratings, CQMs Impact Healthcare Payers. HealthPayerIntelligence News. December 2017.
4. Centers for Medicare & Medicaid Services. Medicare Advantage Plans. 2019; https://www.medicare.gov/sign-up-change-plans/types-of-medicare-health-plans/medicare-advantage-plans.
5. National Committee for Quality Assurance. HEDIS and Performance Measurement. 2019; https://www.ncqa.org/hedis/.
6. National Committee for Quality Assurance. HEDIS Measures and Technical Resources. 2019; https://www.ncqa.org/hedis/measures/.
7. National Committee for Quality Assurance. HEDIS 2019 Data Submission Timeline. 2019; https://www.ncqa.org/hedis/data-submission/hedis-2019-data-submission-timeline/.
8. Hechter RC, Horberg MA, Weisner C, et al. Healthcare Effectiveness Data and Information Set (HEDIS) measures of alcohol and drug treatment initiation and engagement among people living with the human immunodeficiency virus (HIV) and patients without an HIV diagnosis. Substance Abuse. 2019:1–9.
9. Mosen D, Pihlstrom D, Snyder J, Smith N, Shuster E, Rust K. Association of Dental Care with Adherence to HEDIS Measures. The Permanente Journal. 2016;20(1):33–40.
10. Ng-Mak D, Rajagopalan K. Examining quality of care for individuals treated for mental health using the HEDIS mental health quality measures. Current Medical Research and Opinion. 2019;35(1):87–95.
11. Harman JS, Scholle SH, Ng JH, et al. Association of Health Plans’ Healthcare Effectiveness Data and Information Set (HEDIS) Performance With Outcomes Of Enrollees With Diabetes. Medical Care. 2010;48(3):217–223.
12. Harris AHS, Ellerbe L, Phelps TE, et al. Examining the Specification Validity of the HEDIS Quality Measures for Substance Use Disorders. Journal of Substance Abuse Treatment. 2015;53:16–21.
13. Crans Yoon A, Crawford W, Sheikh J, Nakahiro R, Gong A, Schatz M. The HEDIS Medication Management for People with Asthma Measure is Not Related to Improved Asthma Outcomes. The Journal of Allergy and Clinical Immunology: In Practice. 2015;3(4):547-552.