Today s health care practice presents an ongoing challenge to. Guide to Outcomes Measurement for Patients With Low Back Pain Syndromes

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1 Guide to Outcomes Measurement for Patients With Low Back Pain Syndromes Linda Resnik, PT, PhD, OCS 1 Ed Dobrzykowski, PT, MHS, ATC/L 2 Journal of Orthopaedic & Sports Physical Therapy The Guide for Physical Therapist Practice states that the physical therapist determines the expected outcomes for each intervention and engages in outcomes data collection and analysis. Outcomes tracking provides a systematic way for therapists to monitor treatment effectiveness and efficiency. A familiarity with outcome measures for the patient with low back pain is indispensable for therapists in the outpatient orthopaedic setting, where patients with lumbar pain often comprise the majority of the caseload. The therapist must be able to evaluate and choose appropriate measurement tools and understand the clinical meaning of measurements to successfully employ these instruments. The purpose of this article is to review measurement instruments for patients with low back pain and to offer practical guidelines for selection and use of outcome measures for this population. The reliability, validity, sensitivity to change, and utility of common outcome measures are discussed. An overview of generic, disease-specific, and patient-specific tools is provided with specific commentary on the use of the SF-36, SF-12, Oswestry Questionnaire, Roland-Morris Questionnaire, and patient-specific tools. Practical guidelines for utilizing outcome measures in clinical practice and the overall benefits of outcomes tracking are highlighted. J Orthop Sports Phys Ther 2003;33: Today s health care practice presents an ongoing challenge to healthcare therapists, including physical therapists, to be more accountable and to use resources more wisely in the struggle to balance costs and benefits of care. 67 To manage costs and participate in identifying solutions, each therapist must continually assimilate information from the growing body of research with knowledge of their personal results. Outcomes measurement is a process that describes a systematic method to gauge treatment effectiveness and efficiency in daily clinical practice. 70 Treatment effectiveness refers to the outcome of a treatment during the rigors of ordinary and customary care delivery. 70 Treatment efficiency links utilization (ie, outpatient number of visits or inpatient length of stay) and the costs of care with outcome. There is a growing interest among therapists in using outcome measures to make decisions about individual patients. 6,28,79 This trend is consistent with an evidence-based approach to practice (EBP) and an integral aspect of the American Physical Therapy Association vision statement for In EBP, the final step is evaluation of clinical performance, which can be done through outcomes measurement. 2,69 The Guide for Physical Therapist Practice 2 has clearly delineated the role of outcomes and outcomes measurement in physical therapy, gener- 1 Postdoctoral Research Fellow, Center for Gerontology and Health Care Research, Brown University, Providence, RI. 2 Director, Adult Rehabilitation Services, MultiCare Health System, Tacoma, WA. Send correspondence to Linda Resnik, Brown University, Center for Gerontology and Health Care Research, 2 Stimson Avenue, Providence, RI linda_resnik@brown.edu ating a demand for practical guidance in this area. 2 According to the Guide, The physical therapist integrates the 5 elements of patient/client management (examination, evaluation, diagnosis, prognosis, and intervention) in a manner designed to optimize outcomes. 2 Additionally, the therapist is responsible for measuring treatment outcomes. The Guide states, A physical therapist determines the expected outcomes for each intervention and engages in outcomes data collection and analysis. 2 The language contained within the Guide has helped an increasing number of physical therapists to recognize the importance of outcomes. Many therapists, however, lack the requisite training and experience to successfully incorporate outcome measures into their clinical practice. 6 Therapists have concerns about selection, administration, scoring, interpretation, and documentation of outcomes that must be addressed to facilitate their usage. 6 A familiarity with outcome measures for the patient with low back pain is essential for therapists in outpatient orthopaedic practice, where patients with lumbar spine pain often comprise a majority of the caseload. The therapist must be able to evaluate and choose appropriate outcome measures for the patient population, make inferences about changes in measurement scores that occur during CLINICAL COMMENTARY Journal of Orthopaedic & Sports Physical Therapy 307

2 treatment, and deploy this information for clinical decision making. The purpose of this article is to discuss selection of outcome measures for patients with low back pain and to provide guidance for clinical interpretation of outcomes information in this population. SELECTING AN OUTCOME MEASURE: PSYCHOMETRIC PROPERTIES Therapists must possess a basic understanding of the properties of measurement in order to measure outcomes. During the past decade, the American Physical Therapy Association and the American Congress of Rehabilitation Medicine established standards for the use of tests and measures. 3,40 As a result, there has been increased awareness within the physical therapy community that certain psychometric criteria (reliability and validity) need to be met to determine whether an outcome measure is suitable for clinical and research purposes. 63 More recently, responsiveness has been recognized as an important measurement property. 72,82 Reliable measures are consistent and relatively free from random error. Test-retest reliability refers to the consistency of a test result when administered under the same conditions on more than 1 occasion. 60 Because all measures have some degree of random error associated with their repeated administration, the results of any test will have a certain amount of variability. Measurement error may also be introduced when more than 1 rater is used, because multiple raters may have varying degrees of consistency in their scoring of a measurement. Repeatability of a test when administered by more than 1 rater is called interrater reliability. If a test does not have sufficient interrater reliability and different therapists perform the same measurement, its results would not be meaningful. 68 Reliability ranges from 0 to 1 when measured by intraclass correlation coefficients (ICCs) and 1 to1 when measured by indices such as kappa values. Reliability coefficients below 0.50 are considered to have poor reliability, those from 0.50 to 0.75 to have moderate reliability, and those with values above 0.75 to have good reliability. 60 Although reliability scores of 0.90 or more are considered optimal for use in clinical decision making, 68 some researchers regard scores of 0.70 as acceptable for clinical use. 61 However, there is some disagreement among authorities regarding criteria for acceptable reliability. 31,40,80 The greater any measurement error is, the more difficult it is to ascertain true changes (ie, patient progress) in repeated measurements. Minimum detectable change (MDC) is defined as the minimal amount of change that exceeds measurement error. Differences of opinion exist as to what is the optimal method for calculating the MDC. 28,34,92 One method multiplies the standard error of the measurement (SEM) by the z value for 90% confidence level (z = 1.65) and multiplies this value by the square root of 2. 12,75 From a statistical perspective, the patient is considered to have changed only when the difference between the previous score and the current score exceeds the MDC associated with the measurements. 76 Therefore, if the MDC of a particular test is 6 points, a retest difference of more than 6 points would be necessary to be reasonably confident from a statistical perspective that any real change had occurred. The MDC may not be constant across all scores of a test and different degrees of error may exist depending upon where each score falls on the measurement scale. 71 Numerous terms have been used to describe the MDC, including statistically meaningful change, smallest detectable difference, minimum reliable change, and minimally metrically important change. 28 A measure must first be reliable before validity is addressed. Validity is an indication that the measurement actually gauges the concepts that it intends to measure. 60 Other authors have written extensively about the general concepts of validity, which include criterion-based, construct, content, concurrent, and predictive validity. 60 Criterion-based validity addresses the comparison of the measurement to a different measurement of the same construct that has known validity or is considered a gold standard of measurement. 65,68 Construct validity refers to the theoretical foundation supporting the procedures used in a test or measurement. 63 Content validity refers to the measurement s inclusion of relevant elements or substance of the construct to be tested. 68 For example, in patients with low back pain, it is important that measures under consideration contain items pertaining to function, activities of daily living, and occupation or work. Determination of the validity of functional scales has historically relied heavily on the concept of construct validity because in many instances no criterion standard exists for assessing change in health status. 12 Support for construct validity is gauged by the extent to which a measure yields results consistent with the theory underpinning the measurement. Criterion-based validity refers to the degree to which the measure correlates with another criterion that is measured at the same time. 65 Predictive criterion validity is the degree to which the measure is able to predict an important event. 68 Measures with known predictive validity assist clinicians in making statements about expected outcomes or prognoses. Thus measurements with predictive validity can be useful in both treatment and discharge planning. 86 Measurement instruments must be able to detect change when it has occurred and to remain stable when change has not occurred. These properties are 308 J Orthop Sports Phys Ther Volume 33 Number 6 June 2003

3 called responsiveness and sensitivity to change. The ability of an instrument to detect meaningful change can be evaluated both statistically and clinically. 28 While many use responsiveness and sensitivity to change interchangeably, 15,66 others distinguish between these terms, asserting that sensitivity to change is the ability to detect clinically meaningful change. 12 The MDC is a statistical measure of meaningful change and is related to an instrument s reliability. Statistically significant change may not indicate that the change is clinically meaningful. The ability of an instrument to detect relevant clinical change as judged by an external criterion, a type of construct validity, 68,72,75 is considered by some to be the most important measurement property for evaluating a scale s usefulness in making individual patient decisions. 28,74 Relevant clinical change has also been called the minimally clinically important difference (MCID). For an instrument to be used for individual patient decision making, the clinician should appreciate the amount of change in scale points that must occur before the change may be considered meaningful. 28,76 Although MCID data are not available for many popular instruments, these measurements are being reported with greater frequency in the literature. The MCID of the Patient-Specific Functional Scale, for example, has been reported as 3 points. 11 Thus, a retest difference of more than 3 points on this measure would be necessary to be reasonably confident from a clinical perspective that clinically meaningful change had occurred. While most clinicians would expect that the minimum level of statistical change (MDC) would be less than or equal to the MCID, recent studies have suggested that this is not always the case. 28 Further research on the relationship of these 2 measurements is recommended. 28 When the MDC exceeds the MCID, the clinician may choose either value in decision making. The clinician also needs to be aware that some instruments have floor or ceiling effects and are unable to measure change for patients at the extreme ranges. 66 This occurs if the instrument lacks sufficient scale range and a large proportion of patients score at the very top or bottom. In the ceiling effect, there is little room for patients to show improvement, because they already score at the high end of the scale. In the floor effect, the patient scores at the lower range of the scale and therefore the measurement would be unable to detect a decline in status. 12 It is important for clinicians to choose appropriate instruments for their patient populations and to be aware of reported floor and ceiling effects. OUTCOMES IN PATIENTS WITH LOW BACK PAIN SYNDROMES Defining outcomes that are meaningful to stakeholders is a critical first step in outcomes measurement. A central challenge exists in that the definition of treatment success is dependent upon the perspective of the stakeholder. Each maintains their view on what constitutes a good or a meaningful result of care. From the patient and physician perspective, the good outcome is often considered to be the relief of symptoms. 30,54 Employers believe that a positive outcome is defined by the injured employee s return to work. Payers of health care have yet another viewpoint and regard successful outcomes as cost-efficient patient management and patient satisfaction. 30 Traditionally, physical therapists have utilized changes in physical impairments, such as spinal range of motion, abdominal strength, and straight-leg raise as measurements of treatment progress and success. Studies of physical therapists, however, show that they define good outcomes as the learning of long-term management strategies, relief of symptoms, and improved function. 30 Though these quality-of-life outcomes appear to be valued by members of the profession, many physical therapists do not know how to quantify or measure them. 6 With many types of outcomes and measures to choose from, which should physical therapists utilize in patients with low back disorders and how should they use them? We will now examine these outcome measures in further detail. Return to Work An employee s expeditious return to work after an episode of low back pain is an outcome that is highly valued by patients, employers, payers, and society. Physical therapists frequently include diminished work status among the patient problem list and include return to work as one of the goals of treatment. The measurement of the patient s return to work as an outcome of health care, however, has numerous limitations, which suggests that return to work may not be a valid indicator of improvement in patients with low back pain. 25,35 Because improvement of function and quality of life is not necessarily related to work status, use of return to work as an indicator of treatment success is problematic. There are many instances of patients who have made improvement but are not working for various reasons. Return-to-work status fails to account for economic issues of job availability, homemaker and student status, retirement age, or those patients who remain on the job despite impairment. 7 On the opposite end of the spectrum, some patients never leave work, and others resume work while still experiencing limitations in job roles, productivity, and task performance. In these instances, gross measurement of return-to-work status does not measure on-the-job impact of low back pain. 47 Return to work has been shown to be affected by socioeconomic characteristics, economic incentives, job characteristics, and employment status. 5,21,86 Pa- CLINICAL COMMENTARY J Orthop Sports Phys Ther Volume 33 Number 6 June

4 tients whose jobs require a high physical workload are less likely to return to work following back injury. 27,32,41,44,83 Return to work has been associated with sex, age, and time off from work, 8,50,53 as well as time before beginning treatment. 37 Social factors such as marital status and number of children have also been shown to be associated with the rate of return to work. 32,46 Some authors have reported a relationship between return to work and workers compensation status. 4,5,8,84 Physical Impairments The physical therapist s reliance on impairment to assess the outcomes of health care reflects the belief that impairments are the cause of the patient s low back pain and disability and that treatment directed towards these impairments will reduce the patient s pain and disability. 7 Impairments are defined as abnormalities of structure or function, as indicated by signs and symptoms. 2 There are several limitations of using impairments as outcome measures, including lack of standardization of impairments, 26,49,81 and poor reliability of commonly used impairment measurements. 22,43,48,53,61,85 Physical impairment and physical functioning appear to be separate constructs that do not necessarily have a clear linear relationship. 38 Furthermore, some measurements of impairment are not correlated with patient function or disability, bringing into question their meaningfulness as outcome measures. For example, range of motion, and straight-leg raise have been shown to have a poor correlation with disability. 33,57 Further research is needed to determine which measurements of impairment are reliable and valid and may predict the risk for functional limitation and disability. As reliable and valid physical impairment measures are identified, the clinician should consider their use with patients with low back pain syndromes. Health-Related Quality of Life (HRQL) In the literature and within the clinic, the term health-related quality of life is often used interchangeably with the terms functional status, health status, and health outcomes. 14,39 HRQL instruments measure multiple domains of health that often include physical, psychological, emotional, and social dimensions. 38 HRQL instruments are typically questionnaires that patients complete to report their experience of what activities they can do, how often they can do them, and the level of difficulty they have in performing them. HRQL instruments have been widely recommended as an outcome measurement for patients with low back pain. 16,17,23,38 A common misperception among therapists is that patients responses to HRQL questionnaires are subjective and unreliable because patients are reporting their subjective experiences. Therapists have a tendency to view objective clinical measurements of impairment as more reliable. In fact, just the opposite may be true. HRQL instruments have been studied extensively and their reliability and validity are well established, 14,24,29,45,51,52,58,76,78,87 whereas many measurements of physical impairments have been found to be lacking in reliability and validity. 6,48,55,81 COMMON HRQL INSTRUMENTS HRQL instruments are classified as generic, condition specific, or patient specific. Generic instruments are designed for broad use in a variety of patient populations. Condition-specific instruments are designed for use in specific patient populations, such as in patients with low back disorders. Condition-specific instruments have several advantages for the therapist. First, they target specific components of function that are most relevant to the disease or condition and may be more responsive than generic instruments. 59 In addition, many of these instruments can be scored quickly in the clinic and the interpretation of their scores is less complex. Patient-specific measures have been more recently developed to measure activities valued by individual patients. 10 These measures have been suggested for use in patients with low back pain and have been shown to be reliable and valid. 10,79 Because patient-specific scales assess what is most important to each individual patient, they are thought to be particularly suited to measurement of change in the individual patient. 13,79,91 GENERIC INSTRUMENTS SF-36 The SF-36 is among the most researched of the generic HRQL instruments. 62,88 The SF-36 has been studied in populations of patients with low back pain and its reliability and validity have been well established. 82,89 Examples of questions from the SF-36 can be found at the Internet site com. The SF-36 is an approved measure of the Medical Outcomes Trust, a highly regarded clearinghouse for outcome measures with proven psychometric properties and utility. The SF-36 is subdivided into 2 separate health constructs: the physical component summary score (PCS) and the mental component summary score (MCS). 90 Subscales of the SF-36 measure 8 different health concepts including general health, physical functioning, role functioning, bodily pain, mental health, emotional functioning, vitality, and social functioning. 51,52, J Orthop Sports Phys Ther Volume 33 Number 6 June 2003

5 The SF-36 is a self-administered questionnaire that takes the patient 5 to 10 minutes to complete. Information can be collected on paper forms, optical scan forms, direct computer data entry, or voice data entry. There are 2 versions: an acute version (7-day recall) and standard version (30-day recall). Translations have been made in 12 countries, although in the United States, the only official version is in English. The majority of subscales of the SF-36 have been shown to be responsive to change in patients with low back pain and sciatica. 82 Specific subscales of the SF-36, including bodily pain, physical-functioning, and role-functioning scales, have been identified by researchers to be consistently responsive to change in the patient with low back pain. 18,37 One of the advantages of using the SF-36 is that standardized scores have been established for various groups of patients, allowing for comparisons between groups of patients. 52 The clinician who wishes to use SF-36 scores for clinical decision making should evaluate whether a change greater than the MDC or MCID has occurred. Unfortunately, no published data have been reported on the MDC or MCID of the overall SF-36. The publication of more research on this instrument and other instruments based upon the SF-36 will provide the clinician with guidance in individual clinical decision making. SF-12 The SF-12 was developed as an abbreviated version of the SF-36 and contains a subset of 12 items taken from the 8 health concept constructs of the SF The SF-12 evaluates 2 global health constructs: the physical component summary (PCS) and the mental component summary (MCS). 87 The SF-12 was developed to lessen administration time (5 minutes or less), while maintaining acceptable variance explanation. Although it has not been as widely studied as the SF-36, the SF-12 has been found to be reliable and valid. 87 Although the SF-12 PCS scores are useful for making group comparisons, they do not adequately predict SF-36 PCS scores for individual patients, and as such are not recommended for use in individual patient decision making. 62 CONDITION-SPECIFIC INSTRUMENTS Condition- or disease-specific instruments are designed to measure HRQL in specific populations of people. Examples of these instruments include the Roland-Morris Questionnaire (RMQ) and the Oswestry Low Back Pain Disability Questionnaire. Although many other condition-specific instruments have been developed for use with patients with low back pain, this paper will focus only on these 2 instruments because their measurement properties have been studied extensively and both have been recommended for measuring disability related to low back pain. 17 RMQ The RMQ is perhaps the most widely tested of all the disease-specific measures for low back pain. Its reliability, validity, and utility have been well established with this population. 71,76,78 The tool consists of 24 questions related to pain and function. Examples of questions are shown in Table 1. The RMQ takes 5 minutes to complete and only 1 minute to score. The questionnaire is scored on a scale of 0 to 24, with 0 representing no pain and normal function and 24 representing maximum pain and dysfunction. Each item is given a score of either a 1 (agree with statement) or 0 (disagree with statement). Scoring can be done easily by the therapist. The RMQ has been studied extensively. 12,72,76,78 One study reported that 68% of patients with mechanical low back pain had initial RMQ scores of between 7 and 17, 78 although initial scores vary with the specific patient population. Greater scores (ie, those of patients who respond with more perceived limitations) have been reported for patients with radiculopathy and for those with acute versus chronic back pain. 45 Several researchers have calculated that 4 to 5 points are the MDC for this scale. 76,78 A more recent study reported MDC of 8.6 to 9.5 points. 15 An MDC of 5 points represents a change of approximately 20% of the scale range. Reports of sensitivity to change suggest that clinically meaningful change varies depending upon the patient s initial score. For patients with low RMQ scores, clinically important changes occurred with changes that were less than 5 points, and for those with higher initial scores, clinically important changes required a change in the score that was greater than 5 points (Table 2). 64,78 TABLE 1. Examples of questions used in the Roland-Morris Questionnaire. (Scoring: 1 point if patient agrees, 0 points if patient disagrees.) The patient indicates whether they agree or disagree with the statement: I stay at home most of the time because of my back. Because of my back, I try not to bend or kneel down. I only walk short distances because of my back pain. TABLE 2. Minimally clinically important difference for the Roland-Morris Questionnaire (RMQ). 28, points for those with intake RMQ scores of <9 5 9 points for those with intake RMQ scores of points for those with intake RMQ scores of >16 CLINICAL COMMENTARY J Orthop Sports Phys Ther Volume 33 Number 6 June

6 Case Example A 45-year-old woman presents with low back pain and radiating pain in the left leg from the anterior thigh to the knee. She reports that her problem began 2 weeks previously when she bent over to lift groceries from the trunk of her car. The therapist has the patient complete the RMQ prior to the initial evaluation. The therapist scores the questionnaire before beginning the history and evaluation. The initial score on the RMQ is 20 out of 24. The therapist realizes that this score is consistent with other patients with acute symptoms and radiculopathy. 45 The therapist completes the initial evaluation, documents the RMQ score, and establishes a short-term (2-week) goal to decrease the RMQ to 11 out of 24, and a long-term (5-week) goal as 4 out of 24. These scores were chosen because the therapist knows that the reported MCID for the RMQ varies depending upon the initial score. 78 For initial RMQ scores above 16 points, a change of 8 to 13 points is necessary to confidently determine that the patient has made a true change. 78 When the therapist readministers the RMQ at 2 weeks, the score will assist the therapist in evaluating the patient status and the effectiveness of her program. The long-term goal was chosen based on earlier work indicating that the majority of patients who had met their goals in physical therapy had RMQ scores of 4 or below. 73 Oswestry Low Back Pain Disability Questionnaire The Oswestry Low Back Pain Disability Questionnaire has been shown to be reliable and valid for use with patients with low back pain. 9,24,45,79 The Oswestry Questionnaire is self-administered by the patient and takes 5 minutes to complete. It includes 10 sections of questions relating to activities of daily living (ADL) and pain. Each section contains 6 statements that describe an increasing degree of severity relating to a particular activity. These sections are scored from 0 to 5 points. The total raw score is added and multiplied by 2 to provide a percentage of disability. The higher the percentage, the greater the perceived level of disability by the patient (Table 3). Scoring takes about 1 minute. 9,24,28 The Oswestry Questionnaire was first developed in 1980 and has been modified several times. 24 The first change was the removal of a question regarding the use of pain medication and substituting one describing pain severity. 9 The second modification removed a question relating to sex life and replaced it with a TABLE 3. Range of Oswestry Questionnaire scores. 24 * 0 20 minimal disability moderate disability severe disability crippled bed bound or symptom magnifier *Definitions as per Fairbank et al. 24 question regarding changing pain patterns. 9 All 3 versions of the Oswestry Questionnaire are in popular use. Reports of completion errors on Oswestry testing, which show that up to 20% of patient responses to items were left blank and single-response items were answered with multiple responses, have led some to recommend the use of the RMQ over this instrument. 77 Other recent studies utilizing a modified version of the Oswestry Questionnaire did not report problems with low data quality. 15,28 Most authorities consider the 2 measures equally useful and both are recommended for low back pain research. 17 The Oswestry Questionnaire has been shown to be responsive to change in patients with low back pain. 9,24,77,82 While one study reported that the Oswestry Questionnaire was not as sensitive an instrument as the RMQ, 9 another reported that the Oswestry Questionnaire was more sensitive than the RMQ. 15 The SEM for the Oswestry Questionnaire was calculated as 5.4 points and the MCID as 4 to 6 points. 28 While most researchers suggest that a range of 4 to 10 points is necessary to determine significant change, 9,28,77 a recent study reported a MDC of 10.5 to 15 points. 15 PATIENT-SPECIFIC MEASURES A patient-specific measurement has been suggested for use in patients with low back pain and reported to be reliable and valid. 10,79 In practice, the patient is asked by the therapist to select up to 5 main activities which they find difficult to do because of low back pain. Then, the patient is asked to provide a rating of current ability to complete these activities using an 11-point scale ranging from 0 (can t do at all) to 10 (can do fully). Standard use of the test would require reminding the patient of the previously selected activities and scores and then asking the patient to provide a current score. 79 This test is usually administered with significant therapist involvement and takes approximately 15 minutes to administer. Some studies TABLE 4. Minimal detectable change (MDC) and minimum clinically important difference (MCID) of commonly used instruments. Instrument MDC MCID SF-36 Not reported Not reported Roland-Morris 4 5 points 76, points, intake less than 9 28, points, intake , points, intake greater than 16 28, points 15 Oswestry 5 6 points points 9,28,77 6 points 28 Patient-specific 3 points per item 79 3 points per item J Orthop Sports Phys Ther Volume 33 Number 6 June 2003

7 suggest that this instrument may be the most responsive of the HRQL tools, as it specifically addresses problems experienced by the individual patient. 79 Because patients may report up to 5 difficult activities, a total score is not usually calculated. Instead, patient progress is measured by assessing change on each individual item. The minimal detectable change and the minimal clinically important difference are both reported to be 3 points for each identified activity. 79 GUIDELINES FOR USE OF OUTCOME MEASURES There are several methods whereby therapists can begin to utilize outcome measures in their practice. A recommendation is to begin administering diseasespecific or patient-specific instruments as part of routine clinical practice. For therapists who prefer scoring in the clinic, the RMQ or the Oswestry Questionnaire are excellent choices because of their demonstrated reliability, validity, and well-documented sensitivity to change. The following guidelines will assist therapists in using outcome instruments in the clinic: 1) select an instrument with known reliability, validity, and demonstrated sensitivity to change; 2) administer the instrument on intake, reassessment, and upon discharge, and know the suggested time frame for repeat administration; 3) be familiar with the scoring procedure for the instrument; 4) complete the scoring; 5) document the HRQL intake, discharge, and change scores in the patient record; 6) understand the clinical meaning of the range of scores; 7) be familiar with the MDC and MCID for the scale; 8) establish a treatment goal for change of the HRQL score that is greater than the MDC or MCID for the instrument, if these are known; 9) assess changes in HRQL scores and compare to the known MDC for the instrument to determine if true change has been made; 10) track patient outcomes in an organized fashion, ie, using database with other variables of interest, such as demographics and those pertinent to stakeholders; 11) analyze outcomes to evaluate treatment effectiveness and efficiency; 12) while a separate informed consent may not be needed for HRQL survey instruments, make sure that your organization s overall privacy notice to all patients (included with the informed consent) includes the use of items such as HRQL questionnaires. PERFORMANCE MEASUREMENT SYSTEMS Many therapists and providers, as a matter of convenience and cost effectiveness, select a vendor with a standard system for performance measurement and benchmarking of individual clinicians, facilities, and organizations. These systems incorporate measures with the appropriate psychometric criteria and utility for the patient population. Performance measurement systems systematize outcomes data collection and management, and offer computerized scoring. Performance measurement systems can be utilized to evaluate many practice areas including treatment effectiveness, HRQL outcomes, patient satisfaction, resource use, and costs. These information management systems can be useful in quality improvement and marketing for both practices and individual therapists. 19,79 The use of a performance measurement system vendor may simplify data collection and reporting and remove some of the burden of instrument selection, scoring, and analysis from the individual therapist. 79 This selection does not eliminate the responsibility of the therapist to possess a thorough understanding of the measures selected. For example, the therapist needs to be certain that all system measures and instruments have demonstrated reliability and validity. Scoring of measures may be completed by computer and the therapist need not calculate the score. However, the therapist needs to appreciate the clinical meaning of scores to establish goals and evaluate patient progress. Performance measurement systems can generate many different types of analyses and reports. Participating providers need to ensure that the required forms and questionnaires are completed in their entirety for the episode of care for both patients and therapists prior to submission for analysis, otherwise the information management reports will be incomplete and invalid. Accrediting agencies such as the Joint Commission on Accreditation of Healthcare Organizations (JACHO) and the Rehabilitation Accreditation Commission (CARF) have required performance measurement for many years. 20,75 Both CARF- and JACHOaccredited facilities are required to track their results. 20 Institutions that utilize outcome measurement, particularly those which participate with a performance measurement system that meets CARF or JACHO approval, will be in a better position to meet accreditation standards. Third party payers are beginning to ask for outcome measurement and it is expected that they will become more sophisticated in their understanding of this arena. As payers become comfortable with the availability of external benchmarks, providers may be required to participate in a process of performance measurement. Medicare and managed care organiza- CLINICAL COMMENTARY J Orthop Sports Phys Ther Volume 33 Number 6 June

8 tions may someday require outcome measurement to gauge cost effectiveness of care. 56 SUMMARY Therapists need to become more familiar with the use of outcome measures for patients with low back pain syndromes and need to consider using these tools in their daily practice. HRQL measures do not replace tests for pathology, impairment, and pain in classification, diagnosis, and intervention selection. But they serve as reliable, valid, and responsive measures of intervention outcome. Therapists can choose between generic, condition-specific, or patient-specific instruments in any combination. HRQL measures can be scored in the clinic or by computer. Specific guidelines for the use of HRQL instruments have been presented in this paper. Tracking mechanisms can run the gamut from simple documentation in the chart to sophisticated reporting and analysis through participation in a performance measurement system. Therapists and facilities that actively utilize, analyze, and interpret outcomes information benefit in many ways. Ultimately patients will benefit when effective and efficient types of physical therapy services are identified and offered. ACKNOWLEDGEMENTS The authors would like to thank Dennis Hart, PT, PhD, for his guidance, Peter Blanpied, PT, PhD, for his formative manuscript review, and Jill Binkley, PT, for her input regarding this manuscript REFERENCES 1. American Physical Therapy Association. APTA House of Delegates Endorses a Vision of the Future. Alexandria, VA: American Physical Therapy Association; American Physical Therapy Association. Guide to Physical Therapist Practice. Second Edition. American Physical Therapy Association. Phys Ther. 2001;81(1): American Physical Therapy Association. Task Force on Standards for Measurement in Physical Therapy. Standards for tests and measurements in physical therapy practice. Phys Ther. 1991;71(8): Atlas SJ, Chang Y, Kammann E, Keller RB, Deyo RA, Singer DE. Long-term disability and return to work among patients who have a herniated lumbar disc: the effect of disability compensation. J Bone Joint Surg Am. 2000;82(1): Baldwin ML, Johnson WG, Butler RJ. The error of using returns-to-work to measure the outcomes of health care. Am J Ind Med. 1996;29(6): Basmajian J. Physical Rehabilitation Outcomes Measures. Baltimore, MD: Williams and Wilkins; Beattie P, Maher C. The role of functional status questionnaires for low back pain. Aust J Physiother. 1997;43(1): Beissner KL, Saunders RL, McManis BG. Factors related to successful work hardening outcomes. Phys Ther. 1996;76(11): Beurskens AJ, de Vet HC, Koke AJ. Responsiveness of functional status in low back pain: a comparison of different instruments. Pain. 1996;65(1): Beurskens AJ, de Vet HC, Koke AJ, et al. A patientspecific approach for measuring functional status in low back pain. J Manipulative Physiol Ther. 1999;22(3): Binkley J, Stratford PW, Gill C. Interrater reliability of lumbar accessory motion mobility testing. Phys Ther. 1995;75(9): ; discussion Binkley JM, Stratford PW, Lott SA, Riddle DL. The Lower Extremity Functional Scale (LEFS): scale development, measurement properties, and clinical application. North American Orthopaedic Rehabilitation Research Network. Phys Ther. 1999;79(4): Chatman AB, Hyams SP, Neel JM, et al. The Patient- Specific Functional Scale: measurement properties in patients with knee dysfunction. Phys Ther. 1997;77(8): Coons SJ, Rao S, Keininger DL, Hays RD. A comparative review of generic quality-of-life instruments. Pharmacoeconomics. 2000;17(1): Davidson M, Keating JL. A comparison of five low back disability questionnaires: reliability and responsiveness. Phys Ther. 2002;82(1): Delitto A. Are measures of function and disability important in low back care? Phys Ther. 1994;74(5): Deyo RA, Battie M, Beurskens AJ, et al. Outcome measures for low back pain research. A proposal for standardized use. Spine. 1998;23(18): Di Fabio RP, Boissonnault W. Physical therapy and health-related outcomes for patients with common orthopaedic diagnoses. J Orthop Sports Phys Ther. 1998;27(3): Dobrzykowski E. Clinical outcome databases. In: Yeomans SG, ed. The Clinical Application of Outcomes Assessment. Stamford, CT: Appleton and Lange; 2000: 20. Dobrzykowski EA. The methodology of outcomes measurement. J Rehabil Outcomes Meas. 1997;1(1): Dworkin RH, Handlin DS, Richlin DM, Brand L, Vannucci C. Unraveling the effects of compensation, litigation, and employment on treatment response in chronic pain. Pain. 1985;23(1): Egan D, Cole J, Twomey L. The standing forward flexion test: an inaccurate determinant of sacroiliac joint dysfunction. Physiotherapy. 1996;82: Enebo BA. Outcome measures for low back pain: pain inventories and functional disability questionnaires. Chiropr Tech. 1998;10: Fairbank JC, Couper J, Davies JB, O Brien JP. The Oswestry low back pain disability questionnaire. Physiotherapy. 1980;66(8): Feuerstein M, Beattie P. Biobehavioral factors affecting pain and disability in low back pain: mechanisms and assessment. Phys Ther. 1995;75(4): Fitzgerald GK, McClure PW, Beattie P, Riddle DL. Issues in determining treatment effectiveness of manual therapy. Phys Ther. 1994;74(3): Fransen M, Woodward M, Norton R, Coggan C, Dawe M, Sheridan N. Risk factors associated with the transition from acute to chronic occupational back pain. Spine. 2002;27(1): Fritz JM, Irrgang JJ. A comparison of a modified Oswestry Low Back Pain Disability Questionnaire and the Quebec Back Pain Disability Scale. Phys Ther. 2001;81(2): Gatchel RJ, Polatin PB, Mayer TG, Robinson R, Dersh J. Use of the SF-36 Health Status Survey with a chroni- 314 J Orthop Sports Phys Ther Volume 33 Number 6 June 2003

9 cally disabled back pain syndrome: strengths and limitations. J Occup Rehabil. 1998;8: Grimmer K, Sheppard L, Pitt M, Magarey M, Trott P. Differences in stakeholder expectations in the outcome of physiotherapy management of acute low back pain. Int J Qual Health Care. 1999;11(2): Guyatt GH, Feeny DH, Patrick DL. Measuring healthrelated quality of life. Ann Intern Med. 1993;118(8): Haldorsen EMH, Wormgoor MEA, Bjorholt PG, Ursin H. Predictors for outcome of a functional restoration program for low back patients: A 12 months follow-up study. Eur J Phys Med Rehab. 1998;8: Hazard RG, Haugh LD, Green PA, Jones PL. Chronic low back pain: The relationship between patient satisfaction and pain, impairment, and disability outcomes. Spine. 1994;19(8): Hebert R, Spiegelhalter DJ, Brayne C. Setting the minimal metrically detectable change on disability rating scales. Arch Phys Med Rehabil. 1997;78(12): Hunter SJ, Shaha S, Flint D, Tracy DM. Predicting return to work. A long-term follow-up study of railroad workers after low back injuries. Spine. 1998;23(21): Infante-Rivard C, Lortie M. Prognostic factors for return to work after a first compensated episode of back pain. Occup Environ Med. 1996;53(7): Jette DU, Jette AM. Physical therapy and health outcomes in patients with spinal impairments. Phys Ther. 1996;76(9): ; discussion Jette AM. Outcomes research: shifting the dominant research paradigm in physical therapy. Phys Ther. 1995;75(11): Jette AM. Using health-related quality of life measures in physical therapy outcomes research. Phys Ther. 1993;73(8): Johnston MV, Keith RA, Hinderer SR. Measurement standards for interdisciplinary medical rehabilitation. Arch Phys Med Rehabil. 1992;73(12-S):S3 S Krause N, Dasinger LK, Deegan LJ, Rudolph L, Brand RJ. Psychosocial job factors and return-to-work after compensated low back injury: a disability phasespecific analysis. Am J Ind Med. 2001;40(4): Landis JR, Koch GG. The measurement of observer agreement for categorical data. Biometrics. 1977;33(1): Laslett M, Williams M. The reliability of selected pain provocation tests for sacroiliac joint pathology. Spine. 1994;19(11): Leavitt F. The physical exertion factor in compensable work injuries. A hidden flaw in previous research. Spine. 1992;17(3): Leclaire R, Blier F, Fortin L, Proulx R. A cross-sectional study comparing the Oswestry and Roland-Morris Functional Disability scales in two populations of patients with low back pain of different levels of severity. Spine. 1997;22(1): Lehmann TR, Spratt KF, Lehmann KK. Predicting longterm disability in low back injured workers presenting to a spine consultant. Spine. 1993;18(8): Lerner D, Amick BC, 3rd, Rogers WH, Malspeis S, Bungay K, Cynn D. The Work Limitations Questionnaire. Med Care. 2001;39(1): Levangie PK. The association between static pelvic asymmetry and low back pain. Spine. 1999;24(12): Lindsay DM, Meeuwisse WH, Mooney ME, Summersides J. Interrater reliability of manual therapy assessment techniques. Physiother Can. 1995;47(3): Mayer T, Gatchel RJ, Evans T. Effect of age on outcomes of tertiary rehabilitation for chronic disabling spinal disorders. Spine. 2001;26(12): McHorney CA, Ware JE, Jr., Rogers W, Raczek AE, Lu JF. The validity and relative precision of MOS short- and long-form health status scales and Dartmouth COOP charts. Results from the Medical Outcomes Study. Med Care. 1992;30(5 Suppl):MS McHorney CA, Ware JE, Jr., Raczek AE. The MOS 36-Item Short-Form Health Survey (SF-36): II. Psychometric and clinical tests of validity in measuring physical and mental health constructs. Med Care. 1993;31(3): Meijne W, van Neerbos K, Aufdemkampe G, van der Wurff P. Intraexaminer and interexaminer reliability of the Gillet test. J Manipulative Physiol Ther. 1999;22(1): Melles T, McIntosh G, Hall H. Provider, payor, and patient outcome expectation in back pain rehabilitation. J Occup Rehabil. 1995;5(2): Moreland J, Finch E, Stratford P, Balsor B, Gill C. Interrater reliability of six tests of trunk muscle function and endurance. J Orthop Sports Phys Ther. 1997;26(4): Morrison M. Outpatient rehabilitation outcomes: the cost-effectiveness challenge. J Rehabil Outcomes Meas. 1997;1(2): Nattrass CL, Nitschke JE, Disler PB, Chou MJ, Ooi KT. Lumbar spine range of motion as a measure of physical and functional impairment: an investigation of validity. Clin Rehabil. 1999;13(3): Patrick DL, Deyo RA, Atlas SJ, Singer DE, Chapin A, Keller RB. Assessing health-related quality of life in patients with sciatica. Spine. 1995;20(17): ; discussion Patrick DL, Deyo RA. Generic and disease-specific measures in assessing health status and quality of life. Med Care. 1989;27(3 Suppl):S217 S Portney L, Watkins M. Foundations of Clinical Research Applications to Practice. Stamford, CT: Appleton and Lange; Potter NA, Rothstein JM. Intertester reliability for selected clinical tests of the sacroiliac joint. Phys Ther. 1985;65(11): Riddle DL, Lee KT, Stratford PW. Use of SF-36 and SF-12 health status measures: a quantitative comparison for groups versus individual patients. Med Care. 2001;39(8): Riddle DL, Rothstein JM. Intertester reliability of McKenzie s classifications of the syndrome types present in patients with low back pain. Spine. 1993;18(10): Riddle DL, Stratford PW, Binkley JM. Sensitivity to change of the Roland-Morris Back Pain Questionnaire: part 2. Phys Ther. 1998;78(11): Riddle DL, Stratford PW. Interpreting validity indexes for diagnostic tests: an illustration using the Berg balance test. Phys Ther. 1999;79(10): Riddle DL, Stratford PW. Use of generic versus regionspecific functional status measures on patients with cervical spine disorders. Phys Ther. 1998;78(9): Robbins D. Integrating Managed Care and Ethics: Transforming Challenges Into Positive Outcomes. New York, NY: McGraw-Hill; CLINICAL COMMENTARY J Orthop Sports Phys Ther Volume 33 Number 6 June

10 68. Rothstein JM, Echternach J. Primer on Measurement: An introductory Guide to Measurement Issues. Alexandria, VA: APTA; Sackett DL, Rosenberg WM, Gray JA, Haynes RB, Richardson WS. Evidence based medicine: what it is and what it isn t. BMJ. 1996;312(7023): Salive ME, Mayfield JA, Weissman NW. Patient outcomes research teams and the agency for health care policy and research. Health Serv Res. 1990;25(5): Stratford PW, Binkley JM. Applying the results of self-report measures to individual patients: an example using the Roland-Morris Questionnaire. J Orthop Sports Phys Ther. 1999;29(4): Stratford PW, Binkley JM, Riddle DL. Development and initial validation of the back pain functional scale. Spine. 2000;25(16): Stratford PW, Binkley JM, Riddle DL, Guyatt GH. Sensitivity to change of the Roland-Morris Back Pain Questionnaire: part 1. Phys Ther. 1998;78(11): Stratford PW, Binkley JM, Riddle DL, Guyatt GH. Sensitivity to change of the Roland-Morris Back Pain Questionnaire: part 1 [see comments]. Phys Ther. 1998;78(11): Stratford PW, Binkley FM, Riddle DL. Health status measures: strategies and analytic methods for assessing change scores. Phys Ther. 1996;76(10): Stratford PW, Binkley J, Solomon P, Finch E, Gill C, Moreland J. Defining the minimum level of detectable change for the Roland-Morris questionnaire. Phys Ther. 1996;76(4): ; discussion Stratford PW, Binkley J, Solomon P, Gill C, Finch E. Assessing change over time in patients with low back pain. Phys Ther. 1994;74(6): Stratford PW, Finch E, Solomon P, Binkley J, Gill C, Moreland J. Using the Roland-Morris Questionnaire to make decisions about individual patients. Physiother Can. 1996;48: Stratford P, Gill C, Westaway MD. Assessing disability and change on individual patients: a report of a patient specific measure. Physiother Can. 1995;47( Streiner DL, Norman GR. Health Measurement Scales: A Practical Guide to Their Development and Use. New York, NY: Oxford University Press; Strender LE, Sjoblom A, Sundell K, Ludwig R, Taube A. Interexaminer reliability in physical examination of patients with low back pain. Spine. 1997;22(7): Taylor SJ, Taylor AE, Foy MA, Fogg AJB. Responsiveness of common outcome measures for patients with low back pain. Spine. 2001;24: Teasell RW, Bombardier C. Employment-related factors in chronic pain and chronic pain disability. Clin J Pain. 2001;17(4 Suppl):S39 S Tollison CD. Compensation status as a predictor of outcome in nonsurgically treated low back injury. South Med J. 1993;86(11): Van Dillen LR, Sahrmann SA, Norton BJ, et al. Reliability of physical examination items used for classification of patients with low back pain. Phys Ther. 1998;78(9): VanSwearingen JM, Brach JS. Making geriatric assessment work: selecting useful measures. Phys Ther. 2001;81(6): Ware JE, Jr., Kosinski M, Keller SD. A 12-Item Short- Form Health Survey: construction of scales and preliminary tests of reliability and validity. Med Care. 1996;34(3): Ware JE, Jr. SF-36 health survey update. Spine. 2000;25(24): Ware JE, Jr., Sherbourne CD. The MOS 36-item shortform health survey (SF-36). I. Conceptual framework and item selection. Med Care. 1992;30(6): Ware JE, Jr., Snow KK, Kosinski M, Gandek B. SF-36 Health Survey: Manual and Interpretation Guide. Boston, MA: Health Insititute, New England Medical Center; Westaway MD, Stratford PW, Binkley JM. The patientspecific functional scale: validation of its use in persons with neck dysfunction. J Orthop Sports Phys Ther. 1998;27(5): Wilson RW, Gieck JH, Gansneder BM, Perrin DH, Saliba EN, McCue FC, 3rd. Reliability and responsiveness of disablement measures following acute ankle sprains among athletes. J Orthop Sports Phys Ther. 1998;27(5): J Orthop Sports Phys Ther Volume 33 Number 6 June 2003