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  • Measure Summary
  • NQMC:001873
  • Jun 2005
  • NQF-Endorsed Measure

Knee functional status: mean change score in knee functional status of patients with knee impairments receiving physical rehabilitation.

 Focus On Therapeutic Outcomes, Inc. (FOTO).  Patient inquiry®: interactive health analysis®  [CD-ROM]. Knoxville (TN):  Focus On Therapeutic Outcomes, Inc. (FOTO®);  2006.  1 disc.

This is the current release of the measure.

The measure developer reaffirmed the currency of this measure in April 2016.

Primary Measure Domain

Clinical Quality Measures: Outcome

Secondary Measure Domain

Does not apply to this measure


This measure is used to assess functional status of patients who received outpatient rehabilitation through the use of self-report health status questionnaires. Because the measures are taken at intake, during, and at discharge from rehabilitation, change in functional status can be assessed. Measure results are available in Outcomes Profile Reports, which provide 1) information for clinicians to help direct and improve the care of their patients in real time during treatment, and once treatments are complete, 2) a comparison of the clinician's or facility's outcomes and the National Aggregate in the FOTO® Database.


Collection of outcomes following clinical treatment is now commonplace in rehabilitation. (Hart 2002) Clinicians use outcomes to track changes in their patients to assess if the patient is improving with a specific treatment, (Jette & Delitto 1997) if treatment needs to be changed or terminated, (Jette & Jette 1997) and if the patient needs to be referred to another clinician or service. (Jette & Jette 1997) Administrators use outcomes to compare their department's success with other similar departments, to market the department's services, to manage resources required to deliver their clinical services, and to manage their clinicians. (Marino 1997) Researchers analyze outcomes data for a variety of reasons including directing clinical education needs of providers, identifying clinical experts, etc. (Resnik & Hart 2003) The federal government has mandated the collection of outcomes for post-acute rehabilitation in skilled nursing facilities, nursing homes and in patient rehabilitation hospitals, and the government has directed the development of patient assessment instruments designed to collect outcomes in outpatient clinics. (Johnson 2001)

The process of outcomes management is evolving, and now many consider collection of functional status and health and well being the gold standard of outcomes measurement. Patient self-report of health status instruments, which quantify the client's perception of their functional abilities and health and well-being in standardized terms, have been recommended as outcomes tools for effectiveness research studies in rehabilitation. Standardized functional health status measures facilitate assessment of quality and value of clinical care. (Hart 2001)

Evidence for Rationale

Hart DL, Wright BD. Development of an index of physical functional health status in rehabilitation. Arch Phys Med Rehabil. 2002 May;83(5):655-65. PubMed External Web Site Policy

Hart DL. The power of outcomes: FOTO Industrial Outcomes Tool -- Initial assessment. Work. 2001;16(1):39-51. PubMed External Web Site Policy

Jette AM, Delitto A. Physical therapy treatment choices for musculoskeletal impairments. Phys Ther. 1997 Feb;77(2):145-54. PubMed External Web Site Policy

Jette DU, Jette AM. Professional uncertainty and treatment choices by physical therapists. Arch Phys Med Rehabil. 1997 Dec;78(12):1346-51. PubMed External Web Site Policy

Marino MJ. Outcomes management: a new paradigm for leadership. J Rehabil Outcomes Measure. 1997;1(3):58-62.

Resnik L, Hart DL. Using clinical outcomes to identify expert physical therapists. Fort Lauderdale (FL): Institutional Review board for the Protection of Human Subjects, Nov Southeastern University; 2002. 31 p. [70 references]

Primary Health Components

Functional status; physical rehabilitation

Denominator Description

All patients treated at a Focus On Therapeutic Outcomes (FOTO®) participating outpatient rehabilitation clinic for whom both admission and discharge self-report "Knee Functional Status Measure" questionnaires were completed

Numerator Description

The mean of patients' change scores on the "Knee Functional Status Measure"

Type of Evidence Supporting the Criterion of Quality for the Measure

  • One or more research studies published in a National Library of Medicine (NLM) indexed, peer-reviewed journal

Additional Information Supporting Need for the Measure

  • Musculoskeletal impairments account for a larger percentage of conditions for which medical care is sought in the United States (U.S.), and a large proportion of the cost associated with this care is related to the disability caused by these impairments. In 1984, Cunningham and Kelsey reported the overall prevalence of musculoskeletal impairments using data from the National Health and Nutrition Examination Survey (NHANES) I. In the U.S., 32.6% of persons between the ages of 25 and 74 years were affected by some type of physician-observed musculoskeletal impairment, and 29.7% of the population had self-reported musculoskeletal impairments. Impairments related to the spine had the highest prevalence. In the National Medical Care Utilization and Expenditure Survey (NMCUES), about 20% of the 1980 noninstitutionalized population reported having a musculoskeletal problem involving the back or joints that resulted in some type of disability or use of the health care system.
  • Out of 318,427 patients who were treated for orthopedic impairments in 2000-2002 in 552 outpatient rehabilitation clinics participating in the FOTO outcomes process in 40 states, 3.6% had hip impairments, 14.6% had knee impairments, and 6.4% had foot/ankle impairments. From a utilization perspective, they received 9.7+7.7 (mean, SD) visits (range 2 to 100 visits) over 36.4+31 (mean, SD) calendar days duration (range 2 to 365 days).
  • In the U.S., 10.9% of all medical office visits are primarily for musculoskeletal pathology or impairments, with 2% of all visits for back symptoms.
  • NMCUES indicated that 13.3% of total charges for treatment of musculoskeletal conditions was attributed to care given by health care professionals other than physicians, including physical therapists. The cost of health care related to the treatment of musculoskeletal impairments accounted for 8% of total health care expenditures in 1980, ranking third among health problems in terms of costs for civilian noninstitutionalized individuals.

Evidence for Additional Information Supporting Need for the Measure

Hart DL. (Director of Consulting and Research, FOTO: Focus on Therapeutic Outcomes, Inc. Knoxville, TN). Personal communication. 2005 Aug 1.  2 p.

Jette AM, Delitto A. Physical therapy treatment choices for musculoskeletal impairments. Phys Ther. 1997 Feb;77(2):145-54. PubMed External Web Site Policy

Jette DU, Jette AM. Physical therapy and health outcomes in patients with spinal impairments. Phys Ther. 1996 Sep;76(9):930-41; discussion 942-5. PubMed External Web Site Policy

Extent of Measure Testing

The Knee Functional Status measure uses an ever expanding item bank of lower extremity functional status items developed by co-calibrating items in existing functional status questionnaires and developing new items using Item Response Theory (IRT) mathematics. Original work analyzed 20 Lower Extremity Functional Scale (LEFS) items. Two items were deleted because factor analytic and model testing results did not support keeping them. The unidimensionality and local independence of the remaining 18 LEFS items and the hierarchical structure, content validity, person reliability and separation were supported. The functional status measure generated using the computerized adaptive testing process were 70% more efficient than using all 20 LEFS items, and the known group construct validity of the CAT measures was supported. Internal consistency reliability was supported as well. Studies are ongoing to expand the item bank by adding more condition-specific items designed to increase or maintain measure precision while reducing respondent burden.

Evidence for Extent of Measure Testing

Hart DL, Mioduski JE, Stratford PW. Simulated computerized adaptive tests for measuring functional status were efficient with good discriminant validity in patients with hip, knee, or foot/ankle impairments. J Clin Epidemiol. 2005 Jun;58(6):629-38. PubMed External Web Site Policy

State of Use

Current routine use

Current Use


Collaborative inter-organizational quality improvement

Decision-making by consumers about health plan/provider choice

Decision-making by health plans about provider contracting

Internal quality improvement


Public reporting

Quality of care research

Measurement Setting

Ambulatory/Office-based Care

Ancillary Services

Hospital Outpatient

Managed Care Plans

Rehabilitation Centers

Professionals Involved in Delivery of Health Services

Allied Health Personnel

Occupational Therapists

Physical Therapists

Least Aggregated Level of Services Delivery Addressed

Individual Clinicians or Public Health Professionals

Statement of Acceptable Minimum Sample Size


Target Population Age

Age greater than or equal to 14 years

Target Population Gender

Either male or female

National Quality Strategy Aim

Better Care

National Quality Strategy Priority

Prevention and Treatment of Leading Causes of Mortality

IOM Care Need

Getting Better

Living with Illness

IOM Domain


Case Finding Period


Denominator Sampling Frame

Patients associated with provider

Denominator (Index) Event or Characteristic

Clinical Condition

Patient/Individual (Consumer) Characteristic

Therapeutic Intervention

Denominator Time Window

Does not apply to this measure

Denominator Inclusions/Exclusions

All patients with knee impairments treated at a Focus On Therapeutic Outcomes (FOTO®) participating outpatient rehabilitation clinic for whom both admission and discharge self-report "Knee Functional Status Measure" questionnaires were completed

Patient less than 14 years of age

Patients unable to communicate in English, Spanish, Hebrew, Arabic, Russian, or French, or patient does not have a translator/proxy who can communicate in English, Spanish, Hebrew, Arabic, or Russian


Patient factors addressed

Numerator Inclusions/Exclusions

The mean of patients' change scores on the "Knee Functional Status Measure"


Numerator Search Strategy

Fixed time period or point in time

Data Source

Patient/Individual survey

Type of Health State

Functional Status

Instruments Used and/or Associated with the Measure

Focus On Therapeutic Outcomes (FOTO) Knee Functional Status Measure

Measure Specifies Disaggregation

Does not apply to this measure




Weighted Score

Interpretation of Score

Desired value is a higher score

Allowance for Patient or Population Factors

Analysis by subgroup (stratification by individual factors, geographic factors, etc.)

Risk adjustment devised specifically for this measure/condition

Description of Allowance for Patient or Population Factors

Measure outcomes are risk-adjusted by care type, impairment type, severity, acuity, age, and surgical history.

Also, Focus On Therapeutic Outcomes (FOTO®) offers participants the option of adding custom reports to their standard outcomes profile. Some common sorts for these custom reports are by clinician, referral source, payment source, or International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) code.

Standard of Comparison

External comparison at a point in, or interval of, time

External comparison of time trends

Internal time comparison

Original Title

Knee functional status measure.

Measure Collection Name

Patient Inquiry® Software


Focus On Therapeutic Outcomes, Inc. - For Profit Organization


Focus On Therapeutic Outcomes, Inc. - For Profit Organization

Funding Source(s)

Focus On Therapeutic Outcomes, Inc. (FOTO) was solely responsible for funding the research used to develop the Knee Functional Status measure.

Composition of the Group that Developed the Measure

The research team that developed and tested the Knee Functional Status measure was led by Dennis L. Hart, PT, PhD, Director of Consulting and Research, FOTO, Knoxville, TN. Other members of the research team included: Ying-Chih Wang, OT, PhD, Research Assistant, FOTO, Knoxville, TN and Post Doctoral Fellow, Sensory Motor Performance Program, Rehabilitation Institute of Chicago, Chicago, IL; Paul W. Stratford, PT, MS, Professor, School of Rehabilitation Science and Department of Clinical Epidemiology and Biostatistics, McMaster University, Ontario, Canada; and Jerome E. Mioduski, MS, Programmer, FOTO, Knoxville, TN.

Financial Disclosures/Other Potential Conflicts of Interest

Dr. Hart is an investor in and an employee of Focus On Therapeutic Outcomes, Inc. (FOTO). Dr. Wang and Mr. Mioduski are employees of FOTO. Mr. Stratford received no financial rewards and will receive no financial rewards from his work in the projects associated with the development and testing of this measure. Therefore, Mr. Stratford has no financial interests or conflicts of interest in FOTO or the outcomes FOTO collects.


National Quality Forum

NQF Number


Date of Endorsement

2012 Oct 4

Measure Initiative(s)

Physician Quality Reporting System


This measure was not adapted from another source.

Date of Most Current Version in NQMC

2005 Jun

Measure Maintenance


Date of Next Anticipated Revision


Measure Status

This is the current release of the measure.

The measure developer reaffirmed the currency of this measure in April 2016.


 Focus On Therapeutic Outcomes, Inc. (FOTO).  Patient inquiry®: interactive health analysis®  [CD-ROM]. Knoxville (TN):  Focus On Therapeutic Outcomes, Inc. (FOTO®);  2006.  1 disc.

Measure Availability

Source available for purchase from the Focus On Therapeutic Outcomes, Inc. (FOTO®) Web site External Web Site Policy.

For more information, contact FOTO® at Phone: 800-482-3686.

Companion Documents

Focus On Therapeutic Outcomes, Inc. (FOTO). Patient Inquiry™ demo tour [version 5.0]. Knoxville (TN): Focus On Therapeutic Outcomes, Inc. (FOTO®); 8 p.

NQMC Status

This NQMC summary was completed by ECRI on August 18, 2005. The information was verified by the measure developer on August 26, 2005.

This NQMC summary was retrofitted into the new template on May 10, 2011.

The information was reaffirmed by the measure developer on April 25, 2016.

Copyright Statement

This NQMC summary is based on the original measure, which is subject to the measure developer's copyright restrictions.

For more information, contact FOTO, Inc., phone: 800-482-3686; e-mail:; Web site: External Web Site Policy.

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