Outcome assessment in low back pain: how low can you go?


The present study examined the psychometric characteristics of a “core-set” of six individual questions (on pain, function, symptom-specific well-being, work disability, social disability and satisfaction) for use in low back pain (LBP) outcome assessment. A questionnaire booklet was administered to 277 German-speaking LBP patients with a range of common diagnoses, before and 6 months after surgical (N=187) or conservative (N=90) treatment. The core-set items were embedded in the booklet alongside validated ‘reference’ questionnaires: Likert scales for back/leg pain; Roland and Morris disability scale; WHO Quality of Life scale; Psychological General Well-Being Index. A further 45 patients with chronic LBP completed the booklet twice in 1–2 weeks. The minimal reliability (similar to Cronbach’s alpha) for each core item was 0.42–0.78, increasing to 0.84 for a composite index score comprising all items plus an additional question on general well-being (‘quality of life’). Floor or ceiling effects of 20–50% were observed for some items before surgery (function, symptom-specific well-being) and some items after it (disability, function). The intraclass correlation coefficient (ICC) (“test–retest reliability”) was moderate to excellent (ICC, 0.67–0.95) for the individual core items and excellent (ICC, 0.91) for the composite index score. With the exception of “symptom-specific well-being”, the correlations between each core item and its corresponding reference questionnaire (“validity”) were between 0.61 and 0.79. Both the composite index and the individual items differentiated (P<0.001) between the severity of the back problem in surgical and conservative patients (validity). The composite index score had an effect size (sensitivity to change) of 0.95, which was larger than most of the reference questionnaires (0.47–1.01); for individual core items, the effect sizes were 0.52–0.87. The core items provide a simple, practical, reliable, valid and sensitive assessment of outcome in LBP patients. We recommend the widespread and consistent use of the core-set items and their composite score index to promote standardisation of outcome measurements in clinical trials, multicentre studies, routine quality management and surgical registry systems.

This is a preview of subscription content, log in to check access.

Fig. 1
Fig. 2


  1. 1.

    Altman DG, Bland JM (1994) Statistics notes: Diagnostic tests 3: receiver operating characteristic plots. BMJ 309:188

    CAS  PubMed  Google Scholar 

  2. 2.

    Beaton DE (2000) Understanding the relevance of measured change through studies of responsiveness. Spine 25:3192–3199

    Article  CAS  PubMed  Google Scholar 

  3. 3.

    Beurskens AJ, de Vet HC, Köke AJ, van der Heijden GJ, Knipschild PG (1995) Measuring the functional status of patients with low back pain/assessment of the quality of four disease-specific questionnaires. Spine 20:1017–1028

    CAS  PubMed  Google Scholar 

  4. 4.

    Beurskens AJHM, de Vet HCW, Köke (1996) Responsiveness of functional status in low back pain: a comparison of different instruments. Pain 65:71–76

    Article  CAS  PubMed  Google Scholar 

  5. 5.

    Bolognese JA, Schnitzer TJ, Ehrich EW (2003) Response relationship of VAS and Likert scales in osteoarthritis efficacy measurement. Osteoarthritis and Cartilage 11:499–507

    Article  CAS  PubMed  Google Scholar 

  6. 6.

    Bombardier C (2000) Outcome assessments in the evaluation of treatment of spinal disorders: introduction. Spine 25:3097–3099

    Article  CAS  PubMed  Google Scholar 

  7. 7.

    Boos N, Semmer N, Elfering A, Schade V, Gal I, Zanetti M, Kissling R, Buchegger N, Hodler J, Main CJ (2000) Natural history of individuals with asymptomatic disc abnormalities in magnetic resonance imaging. Predictors of low back pain-related medical consultation and work incapacity. Spine 25:1484–1492

    Article  CAS  PubMed  Google Scholar 

  8. 8.

    Bullinger M, Heinisch M, Ludwig M, Geier S (1990) Skalen zur Erfassung des Wohlbefindens: Psychometrische Analysen zum “Profile of Mood States” (POMS) und zum “Psychological General Wellbeing Index” (PGWI). Zeitschrift für Differentielle und Diagnostische Psychologie 11:53–61

    Google Scholar 

  9. 9.

    Cohen J (1988) Statistical power analysis for the behavioral sciences. Lawrence Earlbaum Associates, Hillsdale

    Google Scholar 

  10. 10.

    Cummins RA, Gullone E (2000) Why we should not use 5-point Likert scales: The case for subjective quality of life measurement. Proceedings of the Second International Conference on Quality of Life in Cities National University of Singapore, Singapore:74–93

  11. 11.

    Davidson M, Keating JL (2002) A comparison of five low back disability questionnaires: reliability and responsiveness. Phys Ther 82:8–24

    PubMed  Google Scholar 

  12. 12.

    Depuy HJ (1984) The Psychological General Well-Being (PGWB) Index. In: Assessment of quality of life in clinical trials of cardiovascular therapies. Le Jacq, New York, pp 170–183

  13. 13.

    Deyo RA, Andersson G, Bombardier C, Cherkin DC, Keller RB, Lee CK, Liang MH, Lipscomb B, Shekelle P, Spratt KF, Weinstein JN (1994) Outcome measures for studying patients with low back pain. Spine 19:2032S–2036S

    CAS  PubMed  Google Scholar 

  14. 14.

    Deyo RA, Battie M, Beurskens AJHM, Bombardier C, Croft P, Koes B, Malmivaara A, Roland M, Von Korff M, Waddell G (1998) Outcome measures for low back pain research. A proposal for standardized use. Spine 23:2003–2013

    Article  CAS  PubMed  Google Scholar 

  15. 15.

    Deyo RA, Centor RM (1986) Assessing the responsiveness of functional scales to clinical change: An analogy to diagnostic test performance. Journal of Chronic Diseases 39:897–906

    Article  CAS  PubMed  Google Scholar 

  16. 16.

    Deyo RA, Diehr P, Patrick DL (1991) Reproducibility and responsiveness of health status measures. Statistics and strategies for evaluation. Controlled Clin Trials 12(Suppl):142–158

    Google Scholar 

  17. 17.

    Edwards P, Roberts I, Clarke M, DiGuiseppi C, Pratap S, Wentz R, Kwan I (2002) Increasing response rates to postal questionnaires: systematic review. BMJ 324:1183–1191

    Article  PubMed  Google Scholar 

  18. 18.

    Exner V (1998) Lebensqualität bei chronischen RückenschmerzenpatientInnen [Quality of life in chronic back-pain patients]. Unpublished Master’s Thesis, University of Basel; Basel, Switzerland

  19. 19.

    Exner V, Keel P (2000) Erfassung der Behinderung bei Patienten mit chronischen Rückenschmerzen. Schmerz 14:392–400

    Article  CAS  PubMed  Google Scholar 

  20. 20.

    Fritz JM, Irrgang JJ (2001) A comparison of a modified Oswestry Low Back Pain Disability Questionnaire and the Quebec Back Pain Disability Scale. Phys Ther 81:776–788

    CAS  PubMed  Google Scholar 

  21. 21.

    Gronblad M, Hupli M, Wennerstrand P, Jarvinen E, Lukinmaa A, Kouri JP, Karaharju EO (1993) Intercorrelation and test-retest reliability of the Pain Disability Index (PDI) and the Oswestry Disability Questionnaire (ODQ) and their correlation with pain intensity in low back pain patients. Clin J Pain 9:189–195

    CAS  PubMed  Google Scholar 

  22. 22.

    Guillemin F, Bombardier C, Beaton D (1993) Cross-cultural adaptation of health-related quality of life measures: literature review and proposed guidelines. J Clin Epidemiol 46:1417–1432

    Article  CAS  PubMed  Google Scholar 

  23. 23.

    Hagg O, Fritzell P, Nordwall A (2003) The clinical importance of changes in outcome scores after treatment for chronic low back pain. Eur Spine J 12:12–20

    Google Scholar 

  24. 24.

    Hopkins WG (2000) Measures of reliability in sports medicine and science. Sports Med 30:1–15

    CAS  PubMed  Google Scholar 

  25. 25.

    Hyland ME (2003) A brief guide to the selection of quality of life instrument Health and Quality of Life Outcomes 1:24

    Article  PubMed  Google Scholar 

  26. 26.

    Kirschner, Guyatt A (1985) A methodological framework for assessing health indices. J Chronic Dis 38:27–36

    Article  PubMed  Google Scholar 

  27. 27.

    Mannion AF, Junge A, Fairbank JCT, Dvorak J, Grob D (2004) Development of a German version of the Oswestry Low Back Index. Part 1: cross-cultural adaptation, reliability, and validity. Eur Spine J. DOI: 10.1007/s00586-004-0815-0

  28. 28.

    Melzack R (1975) The McGill Pain Questionnaire: Major Properties and Scoring Methods. Pain 1:277–299

    Article  CAS  PubMed  Google Scholar 

  29. 29.

    Nunnally JC (1978) Psychometric Theory, McGraw-Hill, New York

    Google Scholar 

  30. 30.

    Pellise F, Alvarez L, Escudero O, Pont A, Ferrer M (2003) Metric characteristics of the six-question “core set” in the evaluation of back pain. Eur Spine J 12:S12–S13

    Google Scholar 

  31. 31.

    Roland M, Morris R (1983) A study of the natural history of back pain. Part 1: Development of a reliable and sensitive measure of disability in low-back pain. Spine 8:141–144

    CAS  PubMed  Google Scholar 

  32. 32.

    Staerkle R, Mannion AF, Elfering A, Junge A, Semmer NK, Jacobshagen N, Grob D, Dvorak J, Boos N (2004) Longitudinal validation of the fear-avoidance beliefs questionnaire (FABQ) in a Swiss-German sample of low back pain patients. Eur Spine J 13:332–340

    Google Scholar 

  33. 33.

    Stratford PW, Binkley J, Solomon P, Gill C, FInch E (1994) Assessing change over time in patients with low back pain. Phys Ther 74:528–533

    CAS  PubMed  Google Scholar 

  34. 34.

    Wanous JP, Hudy MJ (2001) Single-item reliability: a replication and extension. Organizational Research Methods 4:361–375

    Google Scholar 

  35. 35.

    Ward MM (2004) Outcome measurement: health status and quality of life. Curr opin Rheumatol 16:96–101

    Article  PubMed  Google Scholar 

  36. 36.

    WHOQOL group (1998) Development of the World Health Organization WHOQOL-BREF quality of life assessment. The WHOQOL group. Psychol Med 28:551–558

    Google Scholar 

  37. 37.

    WHOQOL group (1998) The World Health Organisation WHOQOL-BREF quality of life assessment (WHOQOL): development and general psychometric properties. Soc Sci Med 46:1569–1585

    Google Scholar 

  38. 38.

    Youdon W (1950) Index for Rating Diagnostic Tests. Cancer 3:32–35

    PubMed  Google Scholar 

Download references

Author information



Corresponding author

Correspondence to Anne F. Mannion.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Mannion, A.F., Elfering, A., Staerkle, R. et al. Outcome assessment in low back pain: how low can you go?. Eur Spine J 14, 1014–1026 (2005). https://doi.org/10.1007/s00586-005-0911-9

Download citation


  • Outcome measures
  • Psychometric properties
  • Low back pain
  • Spine surgery