Weiss AJ, Elixhauser A, Andrews RM. Characteristics of Operating Room Procedures in U.S. Hospitals, 2011: Statistical Brief #170. In: Healthcare Cost and Utilization Project (HCUP) Statistical Briefs. Rockville: Agency for Healthcare Research and Quality (US); 2014.
Fritzell P, Hägg O, Gerdhem P, Abbott A, Songsong A, Parai C, et al. 2018 annual report follow up of spine surgery performed in Sweden in 2017. 2018 [updated 2018 Sep 5; cited Dec 10 2018]. Available from: http://www.4s.nu/pdf/180910_Swespine_%20arsrapport_2018_eng_isbn.pdf.
The Health and Social Care Information Centre. Primary diagnosis: 3 character tables: health and social care information Centre. 2016.
Rajaee SS, Bae HW, Kanim LE, Delamarter RB. Spinal fusion in the United States: analysis of trends from 1998 to 2008. Spine (Phila Pa 1976). 2012;37(1):67–76.
Deyo RA, Gray DT, Kreuter W, Mirza S, Martin BI. United States trends in lumbar fusion surgery for degenerative conditions. Spine (Phila Pa 1976). 2005;30(12):1441–5 discussion 6-7.
Kalakoti P, Missios S, Maiti T, Konar S, Bir S, Bollam P, et al. Inpatient outcomes and postoperative complications after primary versus revision lumbar spinal fusion surgeries for degenerative lumbar disc disease: a national (Nationwide) inpatient sample analysis, 2002-2011. World Neurosurg. 2016;85:114–24.
Fairbank JCT, Davies JB, Couper J, O'Brien JP. The Oswestry low back pain disability questionnaire. Physiotherapy. 1980;66(8):271–3.
Roland M, Morris R. A study of the natural history of back pain. Part I: development of a reliable and sensitive measure of disability in low-back pain. Spine (Phila Pa 1976). 1983;8(2):141–4.
Mannion AF, Junge A, Taimela S, Muntener M, Lorenzo K, Dvorak J. Active therapy for chronic low back pain: part 3. Factors influencing self-rated disability and its change following therapy. Spine (Phila Pa 1976). 2001;26(8):920–9.
Wand BM, Chiffelle LA, O'Connell NE, McAuley JH, Desouza LH. Self-reported assessment of disability and performance-based assessment of disability are influenced by different patient characteristics in acute low back pain. Eur Spine J. 2010;19(4):633–40.
Food and Drug Administration. Guidance for Industry Patient-Reported Outcome Measures: Use in Medical Product Development to Support Labeling Claims. 2009 [updated 2009 Dec 15; cited Dec 10 2018]. Available from: https://www.fda.gov/downloads/drugs/guidances/ucm193282.pdf.
Chiarotto A, Ostelo RW, Boers M, Terwee CB. A systematic review highlights the need to investigate the content validity of patient-reported outcome measures for physical functioning in patients with low back pain. J Clin Epidemiol. 2018;95:73–93.
Gautschi OP, Smoll NR, Corniola MV, Joswig H, Chau I, Hildebrandt G, et al. Validity and reliability of a measurement of objective functional impairment in lumbar degenerative disc disease: the timed up and go (TUG) test. Neurosurgery. 2016;79(2):270–8.
Lin CW, McAuley JH, Macedo L, Barnett DC, Smeets RJ, Verbunt JA. Relationship between physical activity and disability in low back pain: a systematic review and meta-analysis. Pain. 2011;152(3):607–13.
Caporaso F, Pulkovski N, Sprott H, Mannion AF. How well do observed functional limitations explain the variance in Roland Morris scores in patients with chronic non-specific low back pain undergoing physiotherapy? Eur Spine J. 2012;21(SUPPL. 2):S187–S95.
Wittink H. Functional capacity testing in patients with chronic pain. Clin J Pain. 2005;21(3):197–9.
Simmonds MJ, Olson SL, Jones S, Hussein T, Lee CE, Novy D, et al. Psychometric characteristics and clinical usefulness of physical performance tests in patients with low back pain. Spine (Phila Pa 1976). 1998;23(22):2412–21.
Harding VR, Williams AC, Richardson PH, Nicholas MK, Jackson JL, Richardson IH, et al. The development of a battery of measures for assessing physical functioning of chronic pain patients. Pain. 1994;58(3):367–75.
Smeets R, Hijdra HJM, Kester ADM, Hitters MWGC, Knottnerus JA. The usability of six physical performance tasks in a rehabilitation population with chronic low back pain. Clin Rehabil. 2006;20(11):989–98.
Lee CE, Simmonds MJ, Novy DM, Jones S. Self-reports and clinician-measured physical function among patients with low back pain: a comparison. Arch Phys Med Rehabil. 2001;82(2):227–31.
Conway J, Tomkins CC, Haig AJ. Walking assessment in people with lumbar spinal stenosis: capacity, performance, and self-report measures. Spine J. 2011;11(9):816–23.
Teixeira Da Cunha-Filho I, Lima FC, Guimarães FR, Leite HR. Use of physical performance tests in a group of Brazilian Portuguese-speaking individuals with low back pain. Physiother Theory Pract. 2010;26(1):49–55.
Guralnik JM, Branch LG, Cummings SR, Curb JD. Physical performance measures in aging research. J Gerontol. 1989;44(5):M141–6.
de Vet HC, Terwee CB, Mokkink LB, Knol DL. Measurement in medicine: a practical guide. Cambridge: Cambridge University Press; 2011.
Brakenhoff TB, Mitroiu M, Keogh RH, Moons KGM, Groenwold RHH, van Smeden M. Measurement error is often neglected in medical literature: a systematic review. J Clin Epidemiol. 2018;98:89–97.
Brakenhoff TB, van Smeden M, Visseren FLJ, Groenwold RHH. Random measurement error: why worry? An example of cardiovascular risk factors. PLoS One. 2018;13(2):e0192298.
Jakobsson M, Gutke A, Mokkink LB, Smeets R, Lundberg M. Level of evidence for reliability, validity, and responsiveness of physical Ccapacity tasks designed to assess functioning in patients with low back pain: a systematic review using the COSMIN standards. Phys Ther. 2018. https://doi.org/10.1093/ptj/pzy159. [Epub ahead of print].
Mokkink LB, Terwee CB, Patrick DL, Alonso J, Stratford PW, Knol DL, et al. The COSMIN study reached international consensus on taxonomy, terminology, and definitions of measurement properties for health-related patient-reported outcomes. J Clin Epidemiol. 2010;63(7):737–45.
Crosby RD, Kolotkin RL, Williams GR. Defining clinically meaningful change in health-related quality of life. J Clin Epidemiol. 2003;56(5):395–407.
Lotzke H, Jakobsson M, Brisby H, Gutke A, Hägg O, Smeets R, et al. Use of the PREPARE (PREhabilitation, physical activity and exeRcisE) program to improve outcomes after lumbar fusion surgery for severe low back pain: a study protocol of a person-centred randomised controlled trial. BMC Musculoskelet Disord. 2016;17(1):349.
Lundberg M, Styf J, Carlsson SG. A psychometric evaluation of the Tampa scale for Kinesiophobia - from a physiotherapeutic perspective. Physiother Theory Pract. 2004;20(2):121–33.
Zigmond AS, Snaith RP. The hospital anxiety and depression scale. Acta Psychiatr Scand. 1983;67(6):361–70.
Kemani MK, Grimby-Ekman A, Lundgren J, Sullivan M, Lundberg M. Factor structure and internal consistency of a Swedish version of the Pain Catastrophizing Scale. Acta Anaesthesiol Scand. 2019;63(2):259–66.
Fairbank JCT, Pynsent PB. The Oswestry disability index. Spine (Phila Pa 1976). 2000;25(22):2940–53.
Chiarotto A, Maxwell LJ, Terwee CB, Wells GA, Tugwell P, Ostelo RW. Roland-Morris disability questionnaire and Oswestry disability index: which has better measurement properties for measuring physical functioning in nonspecific low Back pain? Systematic Review and Meta-Analysis. Phys Ther. 2016;96(10):1620–37.
Price DD, McGrath PA, Rafii A, Buckingham B. The validation of visual analogue scales as ratio scale measures for chronic and experimental pain. Pain. 1983;17(1):45–56.
Ward MM, Guthrie LC, Alba M. Domain-specific transition questions demonstrated higher validity than global transition questions as anchors for clinically important improvement. J Clin Epidemiol. 2015;68(6):655–61.
Kamper SJ, Ostelo RW, Knol DL, Maher CG, de Vet HC, Hancock MJ. Global Perceived Effect scales provided reliable assessments of health transition in people with musculoskeletal disorders, but ratings are strongly influenced by current status. J Clin Epidemiol. 2010;63(7):760–6.e1.
Hägg O, Fritzell P, Oden A, Nordwall A. Simplifying outcome measurement: evaluation of instruments for measuring outcome after fusion surgery for chronic low back pain. Spine (Phila Pa 1976). 2002;27(11):1213–22.
Terwee CB, Bot SDM, de Boer MR, van der Windt DAWM, Knol DL, Dekker J, et al. Quality criteria were proposed for measurement properties of health status questionnaires. J Clin Epidemiol. 2007;60(1):34–42.
de Vet HC, Bouter LM, Bezemer PD, Beurskens AJHM. Reproducibility and responsiveness of evaluative outcome measures. Int J Technol Assess Health Care. 2001;17(04):479–87.
de Winter JC, Gosling SD, Potter J. Comparing the Pearson and Spearman correlation coefficients across distributions and sample sizes: a tutorial using simulations and empirical data. Psychol Methods. 2016;21(3):273–90.
de Vet HC, Terwee CB, Ostelo RW, Beckerman H, Knol DL, Bouter LM. Minimal changes in health status questionnaires: distinction between minimally detectable change and minimally important change. Health Qual Life Outcomes. 2006;4:54.
de Vet HC, Foumani M, Scholten MA, Jacobs WCH, Stiggelbout AM, Knol DL, et al. Minimally important change values of a measurement instrument depend more on baseline values than on the type of intervention. J Clin Epidemiol. 2015;68(5):518–24.
Demoulin C, Ostelo R, Knottnerus JA, Smeets RJ. What factors influence the measurement properties of the Roland-Morris disability questionnaire? Eur J Pain. 2010;14(2):200–6.
Carpenter J, Bithell J. Bootstrap confidence intervals: when, which, what? A practical guide for medical statisticians. Stat Med. 2000;19(9):1141–64.
Robin X, Turck N, Hainard A, Tiberti N, Lisacek F, Sanchez JC, et al. pROC: an open-source package for R and S+ to analyze and compare ROC curves. BMC Bioinformatics. 2011;12:77.
Revicki D, Hays RD, Cella D, Sloan J. Recommended methods for determining responsiveness and minimally important differences for patient-reported outcomes. J Clin Epidemiol. 2008;61(2):102–9.
Gautschi OP, Joswig H, Corniola MV, Smoll NR, Schaller K, Hildebrandt G, et al. Pre- and postoperative correlation of patient-reported outcome measures with standardized timed up and go (TUG) test results in lumbar degenerative disc disease. Acta Neurochir. 2016;158(10):1875–81.
Andersson EI, Lin CC, Smeets RJ. Performance tests in people with chronic low back pain: responsiveness and minimal clinically important change. Spine (Phila Pa 1976). 2010;35(26):E1559–63.
Strand LI, Anderson B, Lygren H, Skouen JS, Ostelo R, Magnussen LH. Responsiveness to change of 10 physical tests used for patients with back pain. Phys Ther. 2011;91(3):404–15.
Guyatt GH, Juniper EF, Walter SD, Griffith LE, Goldstein RS. Interpreting treatment effects in randomised trials. BMJ. 1998;316(7132):690–3.
de Vet HC, Terluin B, Knol DL, Roorda LD, Mokkink LB, Ostelo RW, et al. Three ways to quantify uncertainty in individually applied "minimally important change" values. J Clin Epidemiol. 2010;63(1):37–45.
Terluin B, Eekhout I, Terwee CB, de Vet HC. Minimal important change (MIC) based on a predictive modeling approach was more precise than MIC based on ROC analysis. J Clin Epidemiol. 2015;68(12):1388–96.
Terluin B, Eekhout I, Terwee CB. The anchor-based minimal important change, based on receiver operating characteristic analysis or predictive modeling, may need to be adjusted for the proportion of improved patients. J Clin Epidemiol. 2017;83:90–100.
Scott W, McCracken LM. Patients' impression of change following treatment for chronic pain: global, specific, a single dimension, or many? J Pain. 2015;16(6):518–26.