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Patient-reported Outcomes

Implementation of Patient-reported Outcome Measures in Total Knee Arthroplasty

Ayers, David C. MD

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Journal of the American Academy of Orthopaedic Surgeons: February 2017 - Volume 25 - Issue - p S48-S50
doi: 10.5435/JAAOS-D-16-00631
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Patient-reported Outcomes and Knee Arthroplasty

Total knee arthroplasty is a successful surgical procedure that provides sustained pain relief and improved physical function to many patients plagued with advanced osteoarthritis. As patients undergo this elective surgery to relieve pain and improve physical function, measures of pain and function before and after surgery are important to assess improvements. Patient-reported outcome measures (PROMs) are validated, standardized patient questionnaires used to measure a patient's pain, physical function, and quality of life. Different types of PROMs exist; some include global scores that summarize physical and emotional functions (eg, SF-36, PCS, and MCS, PROMIS Global),1,2 and others are joint-specific and focus on the replaced joint to assess pain, stiffness, and function (eg, Western Ontario and McMaster Universities Osteoarthritis Index, HOOS, and KOOS).35 Although, historically, PROMs have been mostly used in research, they have now moved into clinical practice to measure an individual patient's pain and function before and after surgery.6 Electronic, internet-based platforms are now available that provide turn-key solutions for PROM collection. The use of PROM is in keeping with the Institute of Medicine Vision for the 21st century7 that includes the use of information technology to support patient-centered, evidence-based decisions. Meanwhile, health care in the United States is moving from a volume-driven system to a value (=quality/cost)-based reimbursement system, where quality (the numerator of the value equation) can be measured using PROMs.

PROMs Move Into Clinical Practice

PROMs have emerged as a key player in the rise of value-based bundled payments reimbursement systems. Orthopaedic surgeons in the United States will obtain reimbursement by reporting PROMs for their total joint arthroplasty patients. The Centers for Medicare and Medicaid Services (CMS) first initiated a voluntary reporting program, the Physician Quality Reporting System (PQRS), which provided an incentive payment for satisfactory reporting of patient-reported outcome data on quality measures for Medicare TKR patients.8 Recently, CMS has launched a pilot program called the Comprehensive Care for Joint Replacement (CJR), the first mandatory bundled payment initiative; CJR began in April 2016 in hospitals within 67 geographic areas.9 Under this initiative, hospitals will receive payments based on quality metrics and patient satisfaction, in which PROMs figure predominantly, for all their total joint arthroplasties. Voluntarily submitting PROM data improves the hospital's quality score and can increase the revenue generated from joint arthroplasty.

Private insurers took notice, and the pay for Performance Quality Reporting is already being used by commercial insurance companies. For instance, Blue Cross of Massachusetts is currently paying hospitals a bonus for the collection of preoperative and 9- to 12-month postoperative PROMs for TKA and THA patients.10 PROM data are also currently used for negotiations and discussions with insurance companies, and between Accountable Care Organization (ACOs) and referring doctors as a measure of quality.

PROM Collection in a Busy Practice

Many physicians worry about collecting PROMs in a busy practice. They know that old-fashioned paper and pencil is unsustainable, and also they cannot wait for Electronic Medical Record (EMR) systems to add PROM capability. How PROMs are introduced into routine use in office practice is critical to the success of the PROM collection process and to completion rates.6 To successfully integrate PROMs in practice, the process needs to be efficient, so no added burden is placed on the patient, staff, or surgeon; it should be done preferably before the visit (at home or in a dedicated space outside the waiting room) and through electronic collection using tablets or laptops. The process of collecting and scoring PROMs should be invisible to surgeons and should not slow down the patient's flow and turnover. The surgeon's involvement in the process should be similar to the “surgeon champion,” sharing with the patient the importance of participation and informing the staff that it is a routine part of clinical practice, not a research project.

To be successful, PROMs must produce value for the visit from which the data are collected. For instance, real-time scoring allows the use of data at the visit through, for example, a Computerized Adaptive Testing-Item Response Theory (CAT-IRT)-enabled electronic collection and scoring system.6 PROM data are then actionable for shared decision making regarding treatment and results of the previous treatment. PROMs can then become a part of routine clinical care, beyond their use for research purposes.

PROM Use Through the Example of FORCE-TJR

Functional and Outcomes Research for Comparative Effectiveness in Total Joint Replacement (FORCE-TJR) has emerged as a leader in the orthopaedic community in PROM collection, interpretation, and analysis.6,11,12 In addition, FORCE-TJR has established U.S. national norms for 30- and 90-day complication rates and PROMs at 6 and 12 months after TJR.

FORCE-TJR, centered at the Orthopedics and Physical Rehabilitation, University of Massachusetts Medical School, is a national, prospective cohort of more than 25,000 TJR patients from more than 150 surgeons. Parallel to the current U.S. surgical practice, 75% of FORCE-TJR patients are enrolled from community-based surgeons, including fellowship-trained and general orthopaedists in urban and rural locations, and from teaching and nonteaching hospitals. Patients are enrolled from six geographically diverse high-volume centers and a representative sample of community orthopaedic practices across 28 states stratified by geography (eg, urban/rural) and clinical volume to ensure a balanced representation of diverse patients and practices.

Participating surgeons invite all TJR patients, and data are gathered from both surgeons and patients during preoperative encounters. Patients are followed at routine intervals (eg, 6 months, 12 months, and annually following surgery) directly by the FORCE research staff for the collection of patient-reported outcomes. Approvals for participation in FORCE-TJR were obtained from the respective Institutional Review Board (IRB), and all participants signed a consent allowing direct contact for future assessments.

FORCE-TJR cohort inclusion criteria consist of electively scheduled primary and revision knee and hip arthroplasty, both unilateral and bilateral, hip resurfacing, and unicompartmental knee arthroplasty. Exclusion criteria include emergent knee/hip arthroplasty for acute fracture, cancer, or other reason. Nonsurgical patients are not included.

Measures and Data Collection

FORCE-TJR collects preoperative, baseline data from patient questionnaires completed during a preoperative encounter. Patient’s self-reported data include demographic information (age, sex, race, marital status, education, insurance, household income, smoking status, height, body mass index (BMI), Charlson comorbidity score, and musculoskeletal comorbidity (pain in the lumbar spine and nonoperative knee and hip joints)). In addition, all patients complete a standardized patient PROM before and after surgery, including the Hip Disability and Osteoarthritis Outcome Score (HOOS) or Knee Injury and Osteoarthritis Outcome Score (KOOS), the global function measure using the Short Form 36 (SF-36) Physical Component Score (PCS), and emotional health using the SF-36 Mental Component Score (MCS). Postoperative joint pain, function, and occurrence of any adverse event or revision are assessed at 6 months, 12 months, and annually following surgery.

Both patients and surgeons have been enthusiastic participants. FORCE-TJR's PROM collection rate is exceeding 85% when U.S. regional registries have struggled with post-TJR response rates in the 20–30% range. In addition, participating surgeons value PROM data. FORCE-TJR established national norms and risk-adjustment models and provides web-based confidential quarterly reports to all participating surgeons. Surgeons have access to patient mix, showing how their patient risk factors compare to others; PROMs can help determine the most optimal timing of surgery for an individual patient. Surgeons have access to data regarding their total joint arthroplasty patients' outcomes such as pain, function, quality of life, and adverse events/readmissions. Surgeons can compare their patients to patients at other sites within FORCE-TJR on pre-TJR pain and function, and on key risk-adjustment factors. Finally, surgeons can use the data to manage bundled payment programs (Bundled Payments for Care Improvements (BPCI), CJR) and other value-based contracts.

Risk-adjusted Outcomes

As CMS started public-reporting readmission,13 risk-adjusted outcomes are important for several reasons. They may drive patient volume since the publicly reported performance data have the potential to direct patients to “top-rated” physicians and hospitals. In addition, risk-adjusted outcomes may spur an ongoing competition as to who is going to have the lowest complication rate, lowest 30-day readmission rate, and the highest PROMs. Risk-adjusted outcomes also have the potential to drive reimbursement. With the implementation of financial penalties at the hospital level, with built-in bundled payment initiatives such as CJR, ACO providers are at risk for total medical expense. Another reason risk-adjusted outcomes are important is to ensure fair comparisons across hospitals and surgeons with regards to outcomes, readmission, and complications. In addition, hospitals differ in managing their patients they treat according to the patient's orthopaedic and medical complexity. In fact, risk adjustment makes comparing hospital outcomes or surgeon outcomes fair, and without them, surgeons and hospitals dealing with the most difficult cases would be at a disadvantage with regard to publicly reported outcomes and reimbursement.14 Lack of risk adjustment threatens patient access, eventually leading to reluctance on the part of surgeons and hospitals to treat those who need it the most. Patient access for complex cases would be significantly limited.

In summary, PROMs have moved into clinical practice as U.S. health care transitions from a volume- to a value-based reimbursement system. Electronic, internet-based platforms are now available to provide turn-key solutions for PROM collection. Successful systems provide real-time, CAT-enabled PROM scoring, so the data are actionable for that visit and become part of routine clinical practice. The FORCE-TJR example demonstrates that PROM collection can be efficient and successful with postoperative collection rates exceeding 85% in more than 200 centers.


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Copyright 2016 by the American Academy of Orthopaedic Surgeons.