Critical Path Network

Revising outcome measures for an established pathway

By Marilyn Hanchett, RN, MA, CPHQ
Clinical Pathway Coordinator
Cindy Enright, RN, MBA
Director of Care Management
Columbia Regional Hospital
Columbia, MO

In 1996, the orthopedic multidisciplinary team of Columbia Regional Hospital developed and implemented a clinical pathway for total knee replacement (TKR). Columbia Regional Hospital is a 100-bed community hospital, which became part of University of Missouri Health Care in 1999. Orthopedics and rehabilitation have traditionally been and remain the highest volume lines of service.

Patient case management is performed by registered nurses using a modified, intensive model that includes social-work support. The case management function emphasizes utilization management, facilitation of the multidisciplinary team approach, and discharge planning. Case managers also serve as primary agents in organizing, revising, and maintaining the institution’s clinical pathways.

Focus on length of stay

 The primary outcome measured during the first phase of this project focused on length of stay (LOS). Following implementation of the new pathway, hospital average length of stay for patients undergoing TKR (DRG 209) has progressively decreased to the current 4.5 days for acute care patients.

There has been no increase in infections, hospital readmissions, or changes in the level of patient satisfaction. Not only has the volume of cases remained high, the hospital has simultaneously achieved a five-star (best) rating by in its 2001 analysis of TKR first surgeries.

The new challenge to case managers has been not only to maintain the established pathway so that it accurately reflects the most current practices but explore alternative outcome measures once LOS had been stabilized within the targeted range. However, case managers quickly realized that differing levels of outcome expectancy among the principal stakeholders in the TKR pathway required a new approach to consensus building in order to sustain the momentum of the project.

The need for a new methodology was recognized when updating potential outcome measures associated with the pathway. Opinions varied widely among the members of the multidisciplinary team, generally reflecting the measurement priorities most closely associated with each role.

In order to focus on broad-based outcome measures and encourage team members to consider data collection beyond their immediate service needs, the literature base on TKR surgery published within the past six years was reviewed. The most frequently cited outcome measures in the published studies were then extracted and compiled for analysis by the team. (See Table 1.)

Table 1: Common Outcome Measures for Total Knee Replacement
This table describes the outcome measures most frequently used in clinical studies specific to total knee replacement. This is not a comprehensive list of all outcome measures reported in the literature.

Outcome Measure


Standard Pre/Post Eval Required


Average-Actual LOS  Compares the LOS of each case to the average of all cases in same category  No  Statistics may be adjusted for comorbidities, severity, and other factors
Average-Actual Charges (or Costs)  Compares charges for each case to the average of all cases in same category No  Organizations are generally more willing to share charge rather than actual cost data
ER Visits and/or Readmission within Six Months of Surgery Measure  Frequency of emergency and/or hospital care for TKR patients  in first six months of DC No  ER/readmissions for other non-TKR surgery problems are not included
Frequency of Pathway Use by Organization Rate of pathway implementation by clinical team; often compared to frequency of variances from the pathway No  Very basic, although common  first measure by organization, most shift quickly to trend analysis of pathway variances
Pre- & Post-Op Knee Scores  Detailed assessment scores for joint function are compared before and after surgery Yes  Short LOS may make any differences reported in these  scores statistically (although not clinically) insignificant
Functional Status Patient’s ability to perform ADLs; some tools may include IADLs Yes  Wide variety of pre/post assessment instruments available
Perceived Health Status  Patient’s personal rating of how well he/she is feeling, responding to treatment, etc. Yes  Wide variety of pre/post assessment instruments available
Patient Satisfaction  Patient’s personal rating of how he/she perceives the overall experience of receiving health care and/or services; often completed by proxy if patient is ill or unable to complete the tool  No  Standardized, validated tool required for benchmarking; often criticized as too "soft" a measure to be meaningful, but considered by customer service experts as essential
Health-Related Quality of Life Patient’s personal rating of how he/she feels about the impact of health or health problems on his or her life  Yes  Generic and specific tools available; specific tools tend to quality yield more "sensitive" results; longitudinal analysis is needed to capture most changes in scores
Incidence of Surgical Site Infection Frequency of wound infection at the surgical site No  Benchmarking and comparative data currently available
Incidence of 
Other Post-Op Complications
Frequency of any other post-op complication  No  Comparative data available from a variety of published sources
Effect of Preadmission Screening and/or Teaching  The impact of comprehensive screening and/or patient education on outcome (usually LOS) of case No  Usually done to cost justify program revisions and/or in conjunction with a special study
Effect of Post-DC Destination  The degree to which DC to another, less-acute setting impacts outcome (usually LOS) of case No 

Used most frequently in international studies with U.S. (e.g., skilled unit, rehab); national data used as the benchmark

The process was led by the case manager, who initially helped the team establish core criteria for outcomes measure selection. It was important that the new criteria support the hospital’s transition from short-term, process-oriented measures, often associated with pathway compliance, to more patient-oriented measures. By first developing a simple yet practical set of selection criteria, the team was able to meet this goal. It was also able to create a conceptual foundation for identification of its key issues as well as team measurement priorities.

The following core criteria were approved by the team:

• The outcome measure must support the hospital’s continuing efforts to maximize operational, financial, and clinical process efficiencies.

• The outcome measure must be based on data which are accurate, available, and accessible.

• The outcome measure must be appropriate for comparative analysis and/or external benchmarking.

• The outcomes measure must be associated with analysis of high-volume, high-risk and/or high-cost care and/or services.

After applying the criteria to the list of potential new outcome measures gleaned from the literature, the case manager then used a multivoting technique popular in quality improvement activities to encourage active participation by all team members.

The results revealed a clear, very strong preference by the team for four specific outcome measures. Analysis of hospital LOS associated with the TKR pathway remained within the top four selected. Added to the list were incidence of surgical site infection, incidence of other postoperative complications, and changes in functional status.

A need for results-based measurement

 It is significant that the measures chosen via the new methodology did not vary substantially from many of the topics studied in the early phases of pathway implementation.

However, unlike the earlier indicators, the criteria-based measures reflected a growing understanding of the need for results-based measurement and deepening appreciation of the need to gather data using reliable and valid tools. (See Table 2.) It was clear from the process that as the team’s knowledge and experience relative to the pathway use increased, so had its understanding of pathway measurement.

Table 2: Progression of Key Outcome Measures Total Knee Replacement Pathway

Examples of outcome measure progression as a pathway moves from the initial phase of implementation and into the maintenance phase of an established clinical tool.

TKR Outcome Measure: Initial, Appropriate for New Pathway  TKR Outcome Measure: Revised, Appropriate for Established Pathway
Short term: Measurable within 30 days  Long(er) term: Trended over 3+ months
Process-oriented with emphasis on compliance with pathway guidelines and specific tasks  Patient-oriented with emphasis on the results or impact of care provided
Reduction in DRG-associated LOS Correlation of targeted LOS to quality of care indicators (e.g., incidence of surgical site infections and/or other complications)
Earlier ambulation, increased activity levels; earlier transfer to rehab  Improvements in disease- and/or joint-specific (as appropriate) functional ability
Patient satisfaction (using hospital-specific tool with limited or no opportunities for benchmarking)  Patient satisfaction (using validated, national tool suitable for benchmarking and specific to hospital unit and/or DRG)
Provision of daily teaching and reinforcement of anticoagulation therapy Incidence of adverse events, including complications, related to anticoagulation therapy

The proposed revisions were presented to the hospital’s utilization review committee, which recommended inclusion of patient satisfaction data. Orthopedic surgeons performing TKRs also reviewed the new outcome measures. The groups served as content experts and provided diversity and objectivity to the final, revised list. This collaboration strengthened the growing consensus regarding outcome measure selection and prioritization for the TKR pathway in 2001. It also dramatically reinforced the need for and effectiveness of consensus building among everyone associated with the pathway.

The project supports the growing base of research, which suggests that as clinical pathways succeed in compressing LOS to the lowest level without jeopardizing quality of care standards, the outcome measures associated with the pathway must expand beyond hospital days/LOS statistics.1

While there is no defined methodology for achieving that, the integrated approach facilitated by the case management team at Columbia Regional Hospital appears to have practical value. Review of current literature, combined with application of case management principles, multidisciplinary teamwork, use of hospital-specific criteria, and collaboration with content experts and physician stakeholders are keys to the success of revising, updating, and expanding the scope of clinical pathways and their associated outcome measures.


1. Stern SH, Singer LB, Weissman SE. Analysis of hospital cost in total knee arthroplasty. Does length of stay matter? Clinical Orthopedics 1995; December(312):36-44. 

Share your pathway successes

Hospital Case Management welcomes guest columns about clinical path development and use. Articles should include any results (length of stay, cost, or process improvements) that use of your pathway has helped achieve and should be from 800 to 1,200 words long. Send article submissions to: Lee Reinauer, editor, Hospital Case Management, P.O. Box 740056, Atlanta, GA 30374. Telephone: (404) 262-5460.