Medical care reimbursement in the United States is currently transitioning from a strictly fee-for-service volume basis to a value-modified volume basis. With the passage of the 2015 Medicare Access and CHIP Reauthorization Act (MACRA), programs such as meaningful use, the Physician Quality Reporting System (PQRS), and Value-based Modifier are being combined into the Merit-based Incentive Payment System (MIPS) and Alternative Payment Methods (APMs).

Within these systems, the value of medical care is being assessed by performance measures. Unfortunately, descriptors for performance measures are not always uniformly applied and acronyms for these descriptors can be confusing. This first of three article attempts to clarify the terminology by defining different kinds of measures.

Most performance measures are reported as a rate and include a numerator, denominator, exclusion criteria, and measure logic. Measures can be conceptualized and categorized in various ways including by measure domain, by National Quality Strategy (NQS) priority, or by the measurement setting. The National Quality Measures Clearinghouse has the following five domains for clinical quality measures: process, access, outcome, structure, and patient experience.

Process measures
Process measures determine whether a particular activity that pertains to improved healthcare outcomes has been performed for, on behalf of, or by a patient. An example of a process measure is "Percentage of surgical patients aged 18 years and older undergoing procedures with the indications for a first OR second generation cephalosporin prophylactic antibiotic who had an order for a first OR second generation cephalosporin for antimicrobial prophylaxis" (AAOS Orthopaedic Preferred Specialty Measure Set, PQRS #21: Preoperative Care: Selection of Prophylactic Antibiotic–First OR Second Generation Cephalosporin).

Access measures
Access measures determine whether patient access to appropriate health care is attained in a timely and appropriate manner from a healthcare organization or clinician. An example of an access measure would be "the percentage of members 12 months to 19 years of age who had a visit with a primary care practitioner in the past year."

Outcome measures
Outcome measures assess the results of health care that are experienced by patients, such as clinical events, recovery and health status, experiences in the health system, and efficiency/cost. An example of an outcomes measure would be "the risk-adjusted rate of in-hospital hip fracture among acute care inpatients aged 65 years and older, per 1,000 discharges."

When considering outcomes in general, it is important to make clear distinctions between the following:

• patient-reported outcomes (PROs)
• patient-reported outcome measures (PROMs)
• patient-reported outcomes performance measures (PRO-PMs)

Confusion can occur because "measure" can refer to both patient-reported outcome measure instruments (the tool used to assess outcomes) and patient-reported outcome measure performance measures (the goal sought) (Fig. 1).

PROs are any report of the status of a patient's health condition that comes directly from the patient, without interpretation of the patient's response by a clinician or anyone else.

PROMs are the instrument, scale, or single-item measure used to assess the PRO concept as perceived by the patient, obtained by directly asking the patient to self-report. Examples would be the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form, PROMIS (Patient-Reported Outcomes Measurement Information System), and the Oswestry Disability Index (ODI).

In 2015, the AAOS convened a Quality Outcomes Data (QOD) Work Group and charged it to investigate and evaluate various PROMs. On Feb. 29, 2016, the AAOS Board of Directors approved the QOD work group's recommended list of PROMs. The list includes general quality of life and treatment outcome instruments, as well as specific instruments for foot and ankle, knee, hip, shoulder, elbow, wrist, hand, and spine. See the online version of this article for a link to the list.

PRO-PMs are performance measures based on PROM data aggregated for an accountable healthcare entity. An example would be the Minnesota Community Measurement (MNCM) Total Knee Replacement–Functional Status measure, which assesses the average change between preoperative and one-year (9 to 15 months) postoperative functional status as measured with the Oxford Knee Score. The patient population is adults age 18 and older who underwent a primary total knee replacement between Jan. 1 and Dec. 31, 2013.

Structural measures
Structural measures ascertain whether a healthcare organization or provider has the capability to provide a particular care or service. An example of a structural measure would be the implementation of computerized prescription order entry (CPOE).

Patient experience measures
Patient experience measures document patients' or enrollees' reports of observations of and participation in health care, or assessment of any resulting change in their health. One example of this type of measure is CAHPS (Consumer Assessment of Healthcare Providers and Systems).

Composite measures
Composite measures combine two or more measures, each of which individually reflects quality of care, into a single performance measure with a single score.

Cross-cutting measures
Cross-cutting measures are broadly applicable across multiple clinical settings and eligible professionals (EPs) or group practices within a variety of specialties. The requirement to report cross-cutting measures was added to the PQRS program in 2015 and is triggered if an EP or a group practice bills a face-to-face encounter.

The Centers for Medicare & Medicaid Services defines a face-to-face encounter as an instance in which the EP or group practice billed for services that are associated with face-to-face encounters under the Physician Fee Schedule. This includes general office visits, outpatient visits, and surgical procedure codes; however, telehealth visits are not considered as face-to-face encounters.

An example of a cross-cutting measure is PQRS #131–NQF #0420, Pain Assessment and Follow-Up: Percentage of visits for patients aged 18 years and older with documentation of a pain assessment using a standardized tool(s) on each visit AND documentation of a follow-up plan when pain is present. This measure is in the Communication and Care Coordination NQS Domain, and may be reported using the Claims, Registry or Measure Groups method. The online version of this article has a link to the PQRS cross-cutting list for 2016.

AAOS Orthopaedic Preferred Specialty Measure Set
The AAOS Orthopaedic Preferred Specialty Measure Set was assembled by the AAOS Performance Measures Committee. It lists the 2016 PQRS measures that orthopaedic surgeons can use to comply with current reporting requirements. This set of preferred measures was approved by the AAOS Board of Directors during the 2016 AAOS Annual Meeting. A link to the measure set can be found here.

David R. Chandler, MD, is a member of the AAOS Performance Measures Committee.

Editor's Note: This is one of an ongoing series of articles prepared by the AAOS Performance Measures Committee. For additional information on performance measures, see "CMS and Performance Measure Implementation: Understanding the Impact of the 2-Year Look Back and Capping Out.")

Additional Information:

• Minnesota Department of Health, MN Community Measurement (MNCM). Fact Sheet: Orthopaedic Surgery Outcomes Measures: Total Knee Replacement–Functional Status. Accessed on July 1, 2016.
• What are cross-cutting measures in Physician Quality Reporting System (PQRS) and how do face-to-face encounters trigger possible reporting of a cross-cutting measure? Accessed on July 4, 2016.