Jeffrey N. Katz. THE NORTH AMERICAN SPINE SOCIETY (NASS) LUMBAR SPINE OUTCOME ASSESSMENT INSTRUMENT General Description. Administration.

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1 Arthritis & Rheumatism (Arthritis Care & Research) Vol. 49, No. 5S, October 15, 2003, pp S43 S49 DOI /art , American College of Rheumatology MEASURES OF FUNCTION Measures of Adult Back and Neck Function The North American Spine Society (NASS) Lumbar Spine Outcome Assessment Instrument, Neck Disability Index, Oswestry Low Back Pain Disability Index, Quebec Back Pain Disability Scale, and Roland-Morris Low Back Pain Measure Jeffrey N. Katz THE NORTH AMERICAN SPINE SOCIETY (NASS) LUMBAR SPINE OUTCOME ASSESSMENT INSTRUMENT Purpose. The North American Spine Society (NASS) designated a task force in 1991 to develop an outcome assessment instrument to measure diverse dimensions of the impact of lumbar spine problems. The task force published the instrument in 1996 in Spine (1). The instrument is now part of the American Academy of Orthopedic Surgeons (AAOS) panel of outcomes assessment tools. Content. The tool includes items on patient demographics, medical history, pain, functional status, neurogenic symptoms, employment history, and outcomes of treatment. Developer/contact information. The North American Spine Society developed the instrument. The chief scientist leading the development was Lawren Daltroy, DrPH, of Brigham and Women s Hospital. Contact information is via the American Academy of Orthopedic Surgeons (website: Versions. English. Supported by grant P60 AR and K24 AR from the NIH (NIAMS). Jeffrey N. Katz, MD, MS: Harvard Medical School, Robert Brigham Arthritis and Musculoskeletal Clinical Research Center, and Brigham and Women s Hospital, Boston, Massachusetts. Address correspondence to Jeffrey N. Katz, MD, MS, Division of Rheumatology, Immunology, and Allergy, Brigham and Women s Hospital, B3, 75 Francis Street, Boston, MA jnkatz@partners.org. Submitted for publication April 23, 2003; accepted April 24, Number of items. The instrument contains 34 items aggregated into summative scales along with numerous single items. Subscales. The summative scales include the pain and disability subscale (11 items), neurogenic symptoms (6 items, tapping leg and foot pain, numbness and tingling), job dissatisfaction (3 items), job exertion (5 items), expectations (6 items) and satisfaction (3 items). Populations. Developmental/target. The instrument was used originally on a convenience sample of patients in the office practices of 6 surgeons. Other uses. The instrument has been used in many clinical practices. Method. Self-administered written questionnaire. Difficulty. Eighth grade reading level. Time to complete. 21 minutes (SD 9.2) to complete the entire NASS instrument. Cost/availability. Available from the American Academy of Orthopedic Surgeons at Responses. Scale. Each summative scale has items that range from 1 to 6 (best to worst). Score range. Scale scores also range from 1 to 6 (best to worst). S43

2 S44 Katz Method of scoring. The mean of all items in the scale is used as the scale score. Difficulty. Simple to score. Training to score. None. Norms available. The AAOS has administered the instrument to a population-based sample (details on this survey are available from AAOS). Reliability. Internal consistency. Pain and disability scale alpha 0.93; Neurogenic symptoms scale alpha 0.93; Job dissatisfaction scale alpha 0.90; Job exertion scale alpha 0.84; Expectation scale alpha 0.71; Satisfaction scale alpha Test-retest/stability. Pain and disability scale ICC 0.97; Neurogenic symptoms scale ICC 0.85; Job satisfaction scale ICC 0.99; Job exertion scale ICC 0.93; Expectation scale ICC 0.91; Satisfaction scale ICC not done. Validity. Content/domain/face. Items chosen for relevance and sensibility on inspection by expert clinicians and patients. Construct. The NASS Pain and Disability Scale distinguished preoperative patients from postoperative, and distinguished operative successes from operative failures. Concurrent. The NASS Pain and Disability Scale was correlated with the Visual Analog Pain (VAS) Scale (r 0.84), with the Short Form-36 Pain Scale (r 0.66) and with the Short Form-36 Physical Limitations Scale (r 0.75). Neurogenic symptoms correlated with VAS Pain Scale (r 0.60). Responsiveness. No information available. The NASS instrument includes several useful scales, in particular a scale measuring back pain and disability and a scale measuring neurogenic symptoms. The instrument should be tested further in a range of populations, including patients seen in non-surgical settings, and in longitudinal designs to assess responsiveness. 1. (Original) Daltroy LH, Cats-Baril WL, Katz JN, Fossel AH, Liang MH. The North American Spine Society Lumbar Spine Outcome Assessment Instrument. Spine 1996;21: NECK DISABILITY INDEX Purpose. The Neck Disability Index was developed in the late 1980s to characterize disability due to neck pain (1). Content. The investigators essentially modified the Oswestry Low Back Pain Index so that it would be relevant to neck problems. The final instrument has 10 items, with a format very similar to the Oswestry. Four items are almost identical to the Oswestry (pain intensity, personal care, lifting, sleeping) and the others are different, representing problems more unique to neck pain (e.g., headache, concentration, reading) or general problems (work, driving, recreation). Developer/contact information. Howard Vernon, DC, and Silvano Mior, DC, Division of Research, Canadian Memorial Chiropractic College, Toronto, Ontario, Canada M4G 3E6. Versions. Leak and colleagues also developed an adaptation of the Oswestry for use in neck pain. Their instrument is called the Northwick Park Neck Pain Questionnaire (2). Number of items in scale. Ten. Subscales. Single scale. Populations. Developmental/target. Developed in a cohort of patients with neck pain attending a chiropractic clinic. Method. Self-administered. Difficulty. Simple. Time to complete. Less than 5 minutes. Cost/availability. Available in original publication at no cost. Also available at: adocs/docs_ch37/doc_ch37.09.html#a Responses. Scale. Six ordinal responses per item. Score range. Scored from 0 (no interference with activity) to 5 (maximum difficulty).

3 Adult Back and Neck Function S45 Method of scoring. Total score/total possible score 100. Difficulty. Easy; can score in 1 minute. Norms available. No. alpha 0.80 (3) and 0.92 (1,5). Test-retest/stability. Pearson r 0.89 for scores obtained 2 days apart (1). intraclass correlation coefficient (ICC) 0.89 for scores obtained within 72 hours. Validity. Content/domain/face. The items were developed and reviewed by clinicians experienced in patients with neck pain, and pilot tested in patients with neck pain. Concurrent. Correlation between Neck Disability Index score and McGill Pain Questionnaire total score was r 0.70 (1). Correlation between Neck Disability Index score and 0 10 pain rating scale was r 0.56 (3). Predictive. Correlation between Neck Disability Index score and physical therapist s prognostic rating was r 0.54 (3). Responsiveness. Correlation between changes in NDI scores and self reported change in activity was r 0.60 (1). Minimum detectable level of change based on 90% Confidence interval of the standard error of measurement was 8.4 points of change (3). The Neck Disability Questionnaire is a brief instrument that appears to have acceptable psychometric properties. Further work should establish the performance characteristics of the measure in other patient populations, such as patients undergoing neck surgery or patients evaluated specifically for work associated neck problems. Other instruments have been developed with similar names, including the Northwick Park Neck Pain Questionnaire (2) and the Neck Pain and Disability Scale, modeled on the Million Visual Analog Scale (4). 1. (Original) Vernon H, Mior S. The Neck Pain Disability Index: A study of reliability and validity. J Manipulative Physiol Ther 1991;14: Leak AM, Cooper J, Dyer S, Williams KA, Turner- Stokes L, Frank AO. The Northwick Park Neck Pain Questionnaire, devised to measure neck pain and disability. Br J Rheumatol 1994;33: 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: Wheeler AH, Goolkasian P, Baird AC, Darden BV. Development of the Neck Pain and Disability Scale: item analysis, face and criterion-related validity. Spine 1999;24: Hains F, Waalen J, Mior S. Psychometric properties of the Neck Disability Index. J Manipulative Physiol Ther 1998;21: OSWESTRY LOW BACK PAIN DISABILITY QUESTIONNAIRE Purpose. The Oswestry Low Back Pain Disability Questionnaire was developed in Scotland in the late 1970s (published in 1980) to better characterize the subjective experience of pain and disability in low back pain (1). It is the forerunner of several contemporary low back instruments (including the NASS instrument and the Neck Pain and Disability Questionnaire) and is still used frequently. This is a tribute to its durability and relevance. Content. The instrument contains 10 questions, each of which has 6 ordinal responses. The questions pertain to activities typically affected by low back pain. Developer/contact information. Jeremy Fairbank, Oswestry, Shropshire, UK. Versions. English; adapted for pain and disability scale of the North American Spine Society Outcome Assessment Instrument. Number of items. Ten. Subscales. Single scale. Populations. Developmental/target. Developed in small chronic low back pain population. Used now in many low back pain populations. Other uses. Used in numerous conservative and surgical treatment settings. Method. Self-administered. Difficulty. Simple.

4 S46 Katz Time to complete. 5 minutes or less. Cost/availability. Available in original publication at no cost. Also available at adocs/docs_ch37/doc_37.13.html#a Responses. Scale. Six ordinal responses per item. Score range. Scored from 0 (no interference with activity) to 5 (maximum difficulty). Method of scoring. Total score /total possible score 100. Difficulty. Easy; can score in one minute. Norms available. None. alpha 0.87 (2). Test-retest/stability. Test-retest in 22 patients with chronic low back pain: Pearson r 0.99 (1); Test retest ICC 0.91 (2); Among subjects classified as unchanged, ICC 0.74 (3). Validity. Construct. Distinguished patients who used medications, received compensation, or had work absence from those who did not have these attributes (2). Concurrent. Correlation (Pearson r) of 0.80 with Quebec Back Pain Disability Scale (2). Responsiveness. Among patients self-rated as better after 6 months of conservative therapy, standardized response mean 0.61 for Oswestry (versus 0.92 for Quebec, 1.01 for Roland and 0.44 for Short Form-36 physical function (2). The Oswestry Low Back Pain Disability Questionnaire is over 20 years old and is still used frequently. Its chief advantage is its simplicity. The questionnaire has several disadvantages including awkward phrasing of several items and responses, particularly for North American respondents. The response categories often include more than one concept (such as activity limitation and pain and medication use, all in the same item). The Oswestry has been modified by several authors, usually by replacing the question on sex life due to poor compliance with this question. The modified forms have generally been found to have very similar psychometric properties as the original. 1. (Original) Fairbank JCT, Couper J, Davies JB, O Brien JP. The Oswestry Low Back Pain Disability Questionnaire. Physiotherapy 1980;66: Kopec JA, Esdaile JM, Abrahamowicz M, Abenhaim L, Wood-Dauphinee S, Lamping DL, et al. The Quebec Back Pain Disability Scale: measurement properties. Spine 1995;20: Davidson M, Keating JL, A comparison of five low back disability questionnaires: reliability and responsiveness. Phys Ther 2002;82:8 24. QUEBEC BACK PAIN DISABILITY SCALE Purpose. The Quebec Back Pain Disability Scale was developed by Kopec and colleagues to capture disability due to low back pain. The instrument was published in 1995 (1). Content. The instrument has a conceptual foundation in the World Health Organization (WHO) definition of disability as a restriction in the ability to perform an important activity. It contains 20 items, with Likert responses, on difficulty with specific activities. Developer/contact information. Jacek Kopec, MD, PhD, University of British Columbia, Vancouver, British Columbia, Canada. Versions. English and French versions. Number of items. 20. Subscales. None. Used as a single unidimensional scale. Populations. Developmental/target. Developed in ambulatory patients with low back pain recruited from multiple specialties (physiatry, physiotherapy, family practice, orthopedic surgery, rheumatology). Other uses. Further validation work has been done in a multisite population of patients treated in outpatient physical therapy clinics (2).

5 Adult Back and Neck Function S47 Method. Written questionnaire. Time to complete. Less than 5 minutes. Cost/availability. Available from authors or from publication free of charge. Also available at #A Responses. Scale. Items scored on 6 point Likert scale: 0 not difficult at all; 1 minimally difficult; 2 somewhat difficult; 3 fairly difficult; 4 very difficult; 5 unable to do. Score range. Item scores range 0 5. Method of scoring. Item scores averaged and transformed to Norms available. No. alpha was Test-retest/stability. Test-retest ICC was Test retest ICC was 0.89 in subjects self reported as about the same (2). Test-retest ICC was 0.55 in subjects who reported no improvement over 4 weeks (3). Validity. Content/domain/face. Items suggested by literature on low back pain and opinions of patients with back pain and specialists. Construct. Higher disability scores in patients with radiating pain, prior back surgery, prior hospitalization for low back pain, use of medications for back pain. Concurrent. Strong correlation with Roland Scale (r 0.77), Short Form-36 physical function subscale (r 0.72), Oswestry (r 0.80) and 7- point pain scale (r 0.54). Predictive. Among work disabled, worse scores in patients who remained out of work than in those returning to work. Correlation between change in Quebec scale and patient s rating of change was r 0.67 (3). Responsiveness. Among patients rating themselves as better after 6 months, Quebec scale had similar standardized response mean (0.92) as Roland (1.01) and higher standardized response mean (SRM) than Oswestry (0.61) and Short Form- 36 Physical Function Scale (0.44) (1). Among patients rating themselves as better after 4 weeks, the Quebec scale had a standardized response mean of 1.52, compared with the modified Oswestry (SRM 1.79) and an index of physical impairment (SRM 1.40) (3). Among pregnant patients with back pain rating themselves as improved after 8 weeks, the Quebec scale had standardized response means of 1.18 and 1.12 in two cohorts of patients (4). This is a reliable, valid, responsive measure. It is brief and easy to complete and score. A major appeal is that it is anchored conceptually in the WHO paradigm of disability. The stability of the measure over time in patients reporting no change in their clinical status has been questioned. 1. (Original) Kopec JA, Esdaile JM, Abrahamowicz M, Abenhaim L, Wood-Dauphinee S, Lamping DL, et al. The Quebec Back Pain Disability. Scale: measurement properties. Spine 1995;20: Davidson M, Keating JL, A comparison of five low back disability questionnaires: reliability and responsiveness. Phys Ther 2002;82: Fritz JM, Irrgang JJ. A Comparison of a Modified Oswestry Disability Questionnaire and the Quebec Back Pain Disability Scale. Phys Ther 2001;81: Mens JM. Vleeming A. Snijders CJ. Ronchetti I. Ginai AZ. Stam HJ. Responsiveness of outcome measurements in rehabilitation of patients with posterior pelvic pain since pregnancy. Spine. 2002;27: ROLAND-MORRIS LOW BACK PAIN MEASURE Purpose. Roland and Morris developed a measure intended to capture disability attributable to low back pain across a wide range of domains of functioning (1).

6 S48 Katz Content. The instrument includes 24 statements from the Sickness Impact Profile (a health status measure). The statements covered a range of activities, mostly activities of daily living. The authors added the phrase because of my back to each statement, to make the measure back specific. Developer/contact information. Martin Roland, MA, MRCP, MRCGP and Richard Morris, MSc. Contact is Dr. Roland at Department of General Practice, St. Thomas Hospital Medical School, Lambeth Palace Road, London WE1, UK. Versions. A modified version, the RM-18 (it has 18 rather than the original 24 items), has been developed (2). Number of items. 24. Subscales. None. Populations. Developmental/target. Patients aged 16 to 64 with back pain, presenting to a general practice. Other uses. The measure has been used extensively in primary care and specialty practice, and in patients treated nonoperatively and surgically. Method. Self-administered questionnaire. Training. Little required. Time to complete. Five minutes. Cost/availability. Widely available at no cost Responses. Scale. Each item is scored as zero or one. Score range. The range is 0 24, with higher scores indicating greater disability. Method of scoring. Simple sum of items. Norms available. Yes. alpha 0.90 (3), and 0.87 (4). Test-retest/stability. Twenty persons completed the scale twice within 24 hours, with Pearson r 0.91 (1); 212 patients completed within 2 4 days with ICC 0.91 (3). 47 patients rated as unchanged after six weeks, ICC 0.53 (5). Validity. Content/domain/face. Developed by clinicians. Construct. Distinguished patients who used medications, were receiving compensation, or had work absence from those who did not (3). Concurrent. Correlation with Quebec Back Pain Scale, r 0.77 (3); correlation with Oswestry r 0.82 (2). Responsiveness. Correlation of 0.47 between change in score over time and self rating of global change (3); Standardized response mean of 1.0 in patients self-rated as better after 6 months (3). Standardized response mean of 0.55 in 99 patients with back pain after 6 weeks. (5). The Roland Morris Scale has been used extensively. It is very simple to administer and easy to interpret. The response categories are dichotomous, providing less information per item than scales with multiple response categories. 1. (Original) Roland M, Morris R. A study of the natural history of back pain: Development of a reliable and sensitive measure of disability in low back pain. Spine 1983;8: Stratford PW, Binkley JM. Measurement properties of the RM-18: A modified version of the Roland-Morris Disability Scale. Spine 1997;22: Kopec JA, Esdaile JM, Abrahamowicz M, Abenhaim L, Wood-Dauphinee S, Lamping DL, Williams JI. The Quebec Back Pain Disability Scale: Measurement Properties. Spine 1995;20: Stratford PW, Binkley JM. A comparison study of the Back Pain Functional Scale and the Roland Morris Questionnaire. J Rheumatology 2000;27: Davidson M. Keating JL. A comparison of five low back disability questionnaires: reliability and responsiveness. Phys Ther 2002;82:8 24.

7 Adult Back and Neck Function S49 Summary Table of Adult Back and Neck Function Measures* Measure Content Measure outputs Number of items Response format Method of administration Time for administration Validated populations Reliability Validity Responsiveness NASS Scales for pain and disability; neurogenic symptoms; and other domans Neck Pain and Disability Pain or difficulty with a range of activities (modeled on Oswestry Oswestry Pain or difficulty with a range of activities Quebec Difficulty with a range of activities Roland Limitations due to back problems Subscale scores for each domain 0to100 0to100 0to100 0to24 34 Likert Self 21 minutes Limited surgical, nonsurgical popuations 10 Likert Self 5 minutes Patients with neck pain in chiropractic practice 10 Likert Self minutes Numerous conservative and surgical 20 Likert Self 5 minutes Ambulatory, conservatively treated LBP 24 Yes/no Self 5 minutes Back surgery, conservative therapy, primary care; specialty Excellent Preliminary validation Good to excellent Needs more extensive validation Excellent Extensively validated Excellent Extensively validated Excellent Extensively validated No data Little data Good Excellent Good *NASS North American Spine Society; LBP lower back pain.