{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T15:48:03Z","timestamp":1787240883764,"version":"build-2736575974"},"reference-count":72,"publisher":"Journal of Neurosurgery Publishing Group (JNSPG)","issue":"5","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2021,11]]},"abstract":"\n OBJECTIVE<\/jats:title>\n What is considered \u201cabnormal\u201d in clinical testing is typically defined by simple thresholds derived from normative data. For instance, when testing using the five-repetition sit-to-stand (5R-STS) test, the upper limit of normal (ULN) from a population of spine-healthy volunteers (10.5 seconds) is used to identify objective functional impairment (OFI), but this fails to consider different properties of individuals (e.g., taller and shorter, older and younger). Therefore, the authors developed a personalized testing strategy to quantify patient-specific OFI using machine learning.<\/jats:p>\n <\/jats:sec>\n \n METHODS<\/jats:title>\n Patients with disc herniation, spinal stenosis, spondylolisthesis, or discogenic chronic low-back pain and a population of spine-healthy volunteers, from two prospective studies, were included. A machine learning model was trained on normative data to predict personalized \u201cexpected\u201d test times and their confidence intervals and ULNs (99th percentiles) based on simple demographics. OFI was defined as a test time greater than the personalized ULN. OFI was categorized into types 1 to 3 based on a clustering algorithm. A web app was developed to deploy the model clinically.<\/jats:p>\n <\/jats:sec>\n \n RESULTS<\/jats:title>\n \n Overall, 288 patients and 129 spine-healthy individuals were included. The model predicted \u201cexpected\u201d test times with a mean absolute error of 1.18 (95% CI 1.13\u20131.21) seconds and R\n 2<\/jats:sup>\n of 0.37 (95% CI 0.34\u20130.41). Based on the implemented personalized testing strategy, 191 patients (66.3%) exhibited OFI. Type 1, 2, and 3 impairments were seen in 64 (33.5%), 91 (47.6%), and 36 (18.8%) patients, respectively. Increasing detected levels of OFI were associated with statistically significant increases in subjective functional impairment, extreme anxiety and depression symptoms, being bedridden, extreme pain or discomfort, inability to carry out activities of daily living, and a limited ability to work.\n <\/jats:p>\n <\/jats:sec>\n \n CONCLUSIONS<\/jats:title>\n \n In the era of \u201cprecision medicine,\u201d simple population-based thresholds may eventually not be adequate to monitor quality and safety in neurosurgery. Individualized assessment integrating machine learning techniques provides more detailed and objective clinical assessment. The personalized testing strategy demonstrated concurrent validity with quality-of-life measures, and the freely accessible web app (\n https:\/\/neurosurgery.shinyapps.io\/5RSTS\/<\/jats:ext-link>\n ) enabled clinical application.\n <\/jats:p>\n <\/jats:sec>","DOI":"10.3171\/2021.8.focus21386","type":"journal-article","created":{"date-parts":[[2021,11,1]],"date-time":"2021-11-01T08:23:08Z","timestamp":1635754988000},"page":"E8","source":"Crossref","is-referenced-by-count":5,"title":["Machine learning\u2013augmented objective functional testing in the degenerative spine: quantifying impairment using patient-specific five-repetition sit-to-stand assessment"],"prefix":"10.3171","volume":"51","author":[{"given":"Victor E.","family":"Staartjes","sequence":"first","affiliation":[{"name":"Machine Intelligence in Clinical Neuroscience (MICN) Laboratory, Department of Neurosurgery, Clinical Neuroscience Center, University Hospital Zurich, University of Zurich, Zurich, Switzerland;"},{"name":"Amsterdam UMC, Vrije Universiteit Amsterdam, Department of Neurosurgery, Amsterdam Movement Sciences, Amsterdam;"},{"name":"Department of Neurosurgery, Bergman Clinics, Amsterdam, The Netherlands;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anita M.","family":"Klukowska","sequence":"additional","affiliation":[{"name":"Amsterdam UMC, Vrije Universiteit Amsterdam, Department of Neurosurgery, Amsterdam Movement Sciences, Amsterdam;"},{"name":"Department of Neurosurgery, Bergman Clinics, Amsterdam, The Netherlands;"},{"name":"Department of Surgery, Royal Derby Hospital, Derby, United Kingdom; and"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Moira","family":"Vieli","sequence":"additional","affiliation":[{"name":"Machine Intelligence in Clinical Neuroscience (MICN) Laboratory, Department of Neurosurgery, Clinical Neuroscience Center, University Hospital Zurich, University of Zurich, Zurich, Switzerland;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christiaan H. B. van","family":"Niftrik","sequence":"additional","affiliation":[{"name":"Machine Intelligence in Clinical Neuroscience (MICN) Laboratory, Department of Neurosurgery, Clinical Neuroscience Center, University Hospital Zurich, University of Zurich, Zurich, Switzerland;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martin N.","family":"Stienen","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Cantonal Hospital St. Gallen, St. Gallen, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carlo","family":"Serra","sequence":"additional","affiliation":[{"name":"Machine Intelligence in Clinical Neuroscience (MICN) Laboratory, Department of Neurosurgery, Clinical Neuroscience Center, University Hospital Zurich, University of Zurich, Zurich, Switzerland;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luca","family":"Regli","sequence":"additional","affiliation":[{"name":"Machine Intelligence in Clinical Neuroscience (MICN) Laboratory, Department of Neurosurgery, Clinical Neuroscience Center, University Hospital Zurich, University of Zurich, Zurich, Switzerland;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"W. Peter","family":"Vandertop","sequence":"additional","affiliation":[{"name":"Amsterdam UMC, Vrije Universiteit Amsterdam, Department of Neurosurgery, Amsterdam Movement Sciences, Amsterdam;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marc L.","family":"Schr\u00f6der","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Bergman Clinics, Amsterdam, The Netherlands;"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1754","reference":[{"key":"r1","series-title":"World Neurosurg","doi-asserted-by":"publisher","first-page":"328","DOI":"10.1016\/j.wneu.2017.09.002","article-title":"Current status of worldwide use of Patient-Reported Outcome Measures (PROMs) in spine care","volume":"108","author":"Falavigna A","year":"2017","unstructured":"Falavigna A, Dozza DC, Teles AR, Wong CC, Barbagallo G, Brodke D, Current status of worldwide use of Patient-Reported Outcome Measures (PROMs) in spine care. World Neurosurg. 2017;108:328\u2013335.2889369310.1016\/j.wneu.2017.09.002"},{"issue":"5","key":"r2","series-title":"J Neurosurg","doi-asserted-by":"publisher","first-page":"947","DOI":"10.3171\/2012.7.JNS111622","article-title":"Measuring surgical outcomes in neurosurgery: implementation, analysis, and auditing a prospective series of more than 5000 procedures","volume":"117","author":"Theodosopoulos PV","year":"2012","unstructured":"Theodosopoulos PV, Ringer AJ, McPherson CM, Warnick RE, Kuntz C IV, Zuccarello M, Tew JM Jr. Measuring surgical outcomes in neurosurgery: implementation, analysis, and auditing a prospective series of more than 5000 procedures. J Neurosurg. 2012;117(5):947\u2013954.10.3171\/2012.7.JNS11162222880719"},{"issue":"2","key":"r3","series-title":"Neurosurg Clin N Am","doi-asserted-by":"publisher","first-page":"P265","DOI":"10.1016\/j.nec.2014.11.013","article-title":"Measuring outcomes for neurosurgical procedures","volume":"26","author":"Theodosopoulos PV","year":"2015","unstructured":"Theodosopoulos PV, Ringer AJ. Measuring outcomes for neurosurgical procedures. Neurosurg Clin N Am. 2015;26(2):P265\u2013P269.10.1016\/j.nec.2014.11.013"},{"issue":"3","key":"r4","series-title":"Neurooncol Pract","first-page":"226","article-title":"Quality improvement of neuro-oncology services: integrating the routine collection of patient-reported, health-related quality-of-life measures","volume":"6","author":"Fern\u00e1ndez-M\u00e9ndez R","year":"2019","unstructured":"Fern\u00e1ndez-M\u00e9ndez R, Rastall RJ, Sage WA, Oberg I, Bullen G, Charge AL, Quality improvement of neuro-oncology services: integrating the routine collection of patient-reported, health-related quality-of-life measures. Neurooncol Pract. 2019;6(3):226\u2013236.31385996"},{"issue":"1","key":"r5","series-title":"Neurosurg Focus","doi-asserted-by":"publisher","first-page":"E2","DOI":"10.3171\/2012.10.FOCUS12311","article-title":"The National Neurosurgery Quality and Outcomes Database and NeuroPoint Alliance: rationale, development, and implementation","volume":"34","author":"Asher AL","year":"2013","unstructured":"Asher AL, McCormick PC, Selden NR, Ghogawala Z, McGirt MJ. The National Neurosurgery Quality and Outcomes Database and NeuroPoint Alliance: rationale, development, and implementation. Neurosurg Focus. 2013;34(1):E2.2327826310.3171\/2012.10.FOCUS12311"},{"issue":"4","key":"r6","series-title":"J Neurosurg Anesthesiol","doi-asserted-by":"publisher","first-page":"328","DOI":"10.1097\/ANA.0000000000000474","article-title":"Safety outcomes following spine and cranial neurosurgery: evidence from the National Surgical Quality Improvement Program","volume":"30","author":"Rock AK","year":"2018","unstructured":"Rock AK, Opalak CF, Workman KG, Broaddus WC. Safety outcomes following spine and cranial neurosurgery: evidence from the National Surgical Quality Improvement Program. J Neurosurg Anesthesiol. 2018;30(4):328\u2013336.2913570010.1097\/ANA.0000000000000474"},{"issue":"7","key":"r7","series-title":"Spine J","doi-asserted-by":"publisher","first-page":"1276","DOI":"10.1016\/j.spinee.2019.02.014","article-title":"Objective measures of functional impairment for degenerative diseases of the lumbar spine: a systematic review of the literature","volume":"19","author":"Stienen MN","year":"2019","unstructured":"Stienen MN, Ho AL, Staartjes VE, Maldaner N, Veeravagu A, Desai A, Objective measures of functional impairment for degenerative diseases of the lumbar spine: a systematic review of the literature. Spine J. 2019;19(7):1276\u20131293.3083131610.1016\/j.spinee.2019.02.014"},{"issue":"4","key":"r8","series-title":"J Neurosurg Spine","doi-asserted-by":"publisher","first-page":"380","DOI":"10.3171\/2018.2.SPINE171416","article-title":"The five-repetition sit-to-stand test: evaluation of a simple and objective tool for the assessment of degenerative pathologies of the lumbar spine","volume":"29","author":"Staartjes VE","year":"2018","unstructured":"Staartjes VE, Schr\u00f6der ML. The five-repetition sit-to-stand test: evaluation of a simple and objective tool for the assessment of degenerative pathologies of the lumbar spine. J Neurosurg Spine. 2018;29(4):380\u2013387.2995714710.3171\/2018.2.SPINE171416"},{"issue":"4","key":"r9","series-title":"Eur Spine J","doi-asserted-by":"publisher","first-page":"665","DOI":"10.1007\/s00586-019-05897-3","article-title":"Can objective functional impairment in lumbar degenerative disease be reliably assessed at home using the five-repetition sit-to-stand test? A prospective study","volume":"28","author":"Staartjes VE","year":"2019","unstructured":"Staartjes VE, Beusekamp F, Schr\u00f6der ML. Can objective functional impairment in lumbar degenerative disease be reliably assessed at home using the five-repetition sit-to-stand test? A prospective study. Eur Spine J. 2019;28(4):665\u2013673.10.1007\/s00586-019-05897-3"},{"issue":"22","key":"r10","series-title":"Spine (Phila Pa 1976)","doi-asserted-by":"publisher","first-page":"2412","DOI":"10.1097\/00007632-199811150-00011","article-title":"Psychometric characteristics and clinical usefulness of physical performance tests in patients with low back pain","volume":"23","author":"Simmonds MJ","year":"1998","unstructured":"Simmonds MJ, Olson SL, Jones S, Hussein T, Lee CE, Novy D, Radwan H. Psychometric characteristics and clinical usefulness of physical performance tests in patients with low back pain. Spine (Phila Pa 1976). 1998;23(22):2412\u20132421.10.1097\/00007632-199811150-00011"},{"issue":"1","key":"r11","series-title":"Physiother Theory Pract","doi-asserted-by":"publisher","first-page":"49","DOI":"10.3109\/09593980802602844","article-title":"Use of physical performance tests in a group of Brazilian Portuguese-speaking individuals with low back pain","volume":"26","author":"Teixeira da Cunha-Filho I","year":"2010","unstructured":"Teixeira da Cunha-Filho I, Lima FC, Guimar\u00e3es 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\u201355.10.3109\/09593980802602844"},{"issue":"1","key":"r12","series-title":"J Neurosurg Spine","doi-asserted-by":"publisher","first-page":"4","DOI":"10.3171\/2019.12.SPINE191124","article-title":"Objective functional impairment in lumbar degenerative disease: concurrent validity of the baseline severity stratification for the five-repetition sit-to-stand test","volume":"33","author":"Klukowska AM","year":"2020","unstructured":"Klukowska AM, Schr\u00f6der ML, Stienen MN, Staartjes VE. Objective functional impairment in lumbar degenerative disease: concurrent validity of the baseline severity stratification for the five-repetition sit-to-stand test. J Neurosurg Spine. 2020;33(1):4\u201311.10.3171\/2019.12.SPINE191124"},{"key":"r13","series-title":"BioMed Res Int","doi-asserted-by":"publisher","first-page":"642362","DOI":"10.1155\/2013\/642362","article-title":"Association of seat height and arm position on the five times sit-to-stand test times of stroke survivors","volume":"2013","author":"Ng SSM","year":"2013","unstructured":"Ng SSM, Cheung SY, Lai LSW, Liu ASL, Ieong SHI, Fong SSM. Association of seat height and arm position on the five times sit-to-stand test times of stroke survivors. BioMed Res Int. 2013;2013:642362.2410671110.1155\/2013\/642362"},{"issue":"3","key":"r14","series-title":"J Rehabil Med","doi-asserted-by":"publisher","first-page":"262","DOI":"10.2340\/16501977-1915","article-title":"Five Times Sit-To-Stand test completion times among older women: influence of seat height and arm position","volume":"47","author":"Ng SSM","year":"2015","unstructured":"Ng SSM, Cheung SY, Lai LSW, Liu ASL, Ieong SHI, Fong SSM. Five Times Sit-To-Stand test completion times among older women: influence of seat height and arm position. J Rehabil Med. 2015;47(3):262\u2013266.2543714210.2340\/16501977-1915"},{"issue":"5","key":"r15","series-title":"J Neurosurg Spine","doi-asserted-by":"publisher","first-page":"598","DOI":"10.3171\/2016.11.SPINE16683","article-title":"Validation of the baseline severity stratification of objective functional impairment in lumbar degenerative disc disease","volume":"26","author":"Stienen MN","year":"2017","unstructured":"Stienen MN, Smoll NR, Joswig H, Corniola MV, Schaller K, Hildebrandt G, Gautschi OP. Validation of the baseline severity stratification of objective functional impairment in lumbar degenerative disc disease. J Neurosurg Spine. 2017;26(5):598\u2013604.10.3171\/2016.11.SPINE1668328291406"},{"issue":"2","key":"r16","series-title":"Neurosurgery","doi-asserted-by":"publisher","first-page":"270","DOI":"10.1227\/NEU.0000000000001195","article-title":"Validity and reliability of a measurement of objective functional impairment in lumbar degenerative disc disease: the Timed Up and Go (TUG) test","volume":"79","author":"Gautschi OP","year":"2016","unstructured":"Gautschi OP, Smoll NR, Corniola MV, Joswig H, Chau I, Hildebrandt G, 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\u2013278.2670284010.1227\/NEU.0000000000001195"},{"issue":"13","key":"r17","series-title":"N Engl J Med","doi-asserted-by":"publisher","first-page":"1216","DOI":"10.1056\/NEJMp1606181","article-title":"Predicting the future - big data, machine learning, and clinical medicine","volume":"375","author":"Obermeyer Z","year":"2016","unstructured":"Obermeyer Z, Emanuel EJ. Predicting the future - big data, machine learning, and clinical medicine. N Engl J Med. 2016;375(13):1216\u20131219.10.1056\/NEJMp160618127682033"},{"issue":"7624","key":"r18","series-title":"BMJ","doi-asserted-by":"publisher","first-page":"806","DOI":"10.1136\/bmj.39335.541782.AD","article-title":"Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement: guidelines for reporting observational studies","volume":"335","author":"von Elm E","year":"2007","unstructured":"von Elm E, Altman DG, Egger M, Pocock SJ, G\u00f8tzsche PC, Vandenbroucke JP. Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement: guidelines for reporting observational studies. BMJ. 2007;335(7624):806\u2013808.10.1136\/bmj.39335.541782.AD17947786"},{"issue":"11","key":"r19","series-title":"Thorax","doi-asserted-by":"publisher","first-page":"1015","DOI":"10.1136\/thoraxjnl-2013-203576","article-title":"The five-repetition sit-to-stand test as a functional outcome measure in COPD","volume":"68","author":"Jones SE","year":"2013","unstructured":"Jones SE, Kon SSC, Canavan JL, Patel MS, Clark AL, Nolan CM, The five-repetition sit-to-stand test as a functional outcome measure in COPD. Thorax. 2013;68(11):1015\u20131020.2378337210.1136\/thoraxjnl-2013-203576"},{"key":"r20","series-title":"R: A Language and Environment for Statistical Computing","author":"R Core Team","year":"2021","unstructured":"R Core Team. R: A Language and Environment for Statistical Computing. R Foundation for Statistical Computing; 2021. Accessed September 9, 2021. https:\/\/www.R-project.org\/"},{"key":"r21","series-title":"J Stat Softw","doi-asserted-by":"publisher","first-page":"i07","DOI":"10.18637\/jss.v074.i07","article-title":"Imputation with the R package VIM","volume":"74","author":"Kowarik A","year":"2016","unstructured":"Kowarik A, Templ M. Imputation with the R package VIM. J Stat Softw. 2016;74:i07.10.18637\/jss.v074.i07"},{"key":"r22","series-title":"Handbook of Quantile Regression","doi-asserted-by":"publisher","DOI":"10.1201\/9781315120256","author":"Koenker R","year":"2017","unstructured":"Koenker R, Chernozhukov V, He X, Peng L. Handbook of Quantile Regression. CRC Press; 2017.10.1201\/9781315120256"},{"key":"r23","series-title":"R-project.org","article-title":"quantreg: Quantile regression","author":"Koenker R","unstructured":"Koenker R, Portnoy S, Ng PT, Melly B, Zeilis A, Grosjean P, quantreg: Quantile regression. R-project.org. Accessed September 9, 2021. https:\/\/CRAN.R-project.org\/package=quantreg"},{"issue":"8476","key":"r24","series-title":"Lancet","doi-asserted-by":"publisher","first-page":"307","DOI":"10.1016\/S0140-6736(86)90837-8","article-title":"Statistical methods for assessing agreement between two methods of clinical measurement","volume":"1","author":"Bland JM","year":"1986","unstructured":"Bland JM, Altman DG. Statistical methods for assessing agreement between two methods of clinical measurement. Lancet. 1986;1(8476):307\u2013310.286817210.1016\/S0140-6736(86)90837-8"},{"key":"r25","article-title":"Mosby\u2019s Diagnostic and Laboratory Test Reference","author":"Pagana KD","year":"2018","unstructured":"Pagana KD, Pagana TJ, Pagana TN. Mosby\u2019s Diagnostic and Laboratory Test Reference. Elsevier Health Sciences; 2018."},{"issue":"7","key":"r26","series-title":"J Clin Epidemiol","doi-asserted-by":"publisher","first-page":"737","DOI":"10.1016\/j.jclinepi.2010.02.006","article-title":"The COSMIN study reached international consensus on taxonomy, terminology, and definitions of measurement properties for health-related patient-reported outcomes","volume":"63","author":"Mokkink LB","year":"2010","unstructured":"Mokkink LB, Terwee CB, Patrick DL, Alonso J, Stratford PW, Knol DL, 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\u2013745.2049480410.1016\/j.jclinepi.2010.02.006"},{"issue":"5","key":"r27","series-title":"Neurosurg Rev","doi-asserted-by":"publisher","first-page":"1331","DOI":"10.1007\/s10143-019-01168-3","article-title":"Association of maximum back and leg pain severity with objective functional impairment as assessed by five-repetition sit-to-stand testing: analysis of two prospective studies","volume":"43","author":"Staartjes VE","year":"2020","unstructured":"Staartjes VE, Klukowska AM, Schr\u00f6der ML. Association of maximum back and leg pain severity with objective functional impairment as assessed by five-repetition sit-to-stand testing: analysis of two prospective studies. Neurosurg Rev. 2020;43(5):1331\u20131338.10.1007\/s10143-019-01168-331451936"},{"issue":"1-2","key":"r28","series-title":"Pain","doi-asserted-by":"publisher","first-page":"103","DOI":"10.1016\/j.pain.2006.08.011","article-title":"Impact of low back pain on functional limitations, depressed mood and quality of life in patients with rheumatoid arthritis","volume":"127","author":"Kothe R","year":"2007","unstructured":"Kothe R, Kohlmann T, Klink T, R\u00fcther W, Klinger R. Impact of low back pain on functional limitations, depressed mood and quality of life in patients with rheumatoid arthritis. Pain. 2007;127(1-2):103\u2013108.10.1016\/j.pain.2006.08.01116982148"},{"issue":"9178","key":"r29","series-title":"Lancet","doi-asserted-by":"publisher","first-page":"581","DOI":"10.1016\/S0140-6736(99)01312-4","article-title":"Epidemiological features of chronic low-back pain","volume":"354","author":"Andersson GB","year":"1999","unstructured":"Andersson GB. Epidemiological features of chronic low-back pain. Lancet. 1999;354(9178):581\u2013585.1047071610.1016\/S0140-6736(99)01312-4"},{"issue":"10","key":"r30","series-title":"J Gerontol A Biol Sci Med Sci","doi-asserted-by":"publisher","first-page":"M487","DOI":"10.1093\/gerona\/54.10.M487","article-title":"Low back pain and disability in older women: independent association with difficulty but not inability to perform daily activities","volume":"54","author":"Leveille SG","year":"1999","unstructured":"Leveille SG, Guralnik JM, Hochberg M, Hirsch R, Ferrucci L, Langlois J, Low back pain and disability in older women: independent association with difficulty but not inability to perform daily activities. J Gerontol A Biol Sci Med Sci. 1999;54(10):M487\u2013M493.10.1093\/gerona\/54.10.M487"},{"issue":"20","key":"r31","series-title":"Circulation","doi-asserted-by":"publisher","first-page":"1920","DOI":"10.1161\/CIRCULATIONAHA.115.001593","article-title":"Machine learning in medicine","volume":"132","author":"Deo RC","year":"2015","unstructured":"Deo RC. Machine learning in medicine. Circulation. 2015;132(20):1920\u20131930.10.1161\/CIRCULATIONAHA.115.001593"},{"issue":"14","key":"r32","series-title":"N Engl J Med","doi-asserted-by":"publisher","first-page":"1347","DOI":"10.1056\/NEJMra1814259","article-title":"Machine learning in medicine","volume":"380","author":"Rajkomar A","year":"2019","unstructured":"Rajkomar A, Dean J, Kohane I. Machine learning in medicine. N Engl J Med. 2019;380(14):1347\u20131358.10.1056\/NEJMra1814259"},{"issue":"1","key":"r33","series-title":"Nat Med","doi-asserted-by":"publisher","first-page":"44","DOI":"10.1038\/s41591-018-0300-7","article-title":"High-performance medicine: the convergence of human and artificial intelligence","volume":"25","author":"Topol EJ","year":"2019","unstructured":"Topol EJ. High-performance medicine: the convergence of human and artificial intelligence. Nat Med. 2019;25(1):44\u201356.3061733910.1038\/s41591-018-0300-7"},{"issue":"11","key":"r34","series-title":"JAMA","doi-asserted-by":"publisher","first-page":"1117","DOI":"10.1001\/jama.2014.2135","article-title":"Age-adjusted D-dimer cutoff levels to rule out pulmonary embolism: the ADJUST-PE study","volume":"311","author":"Righini M","year":"2014","unstructured":"Righini M, Van Es J, Den Exter PL, Roy PM, Verschuren F, Ghuysen A, Age-adjusted D-dimer cutoff levels to rule out pulmonary embolism: the ADJUST-PE study. JAMA. 2014;311(11):1117\u20131124.2464360110.1001\/jama.2014.2135"},{"issue":"1","key":"r35","series-title":"Gerontology","doi-asserted-by":"publisher","first-page":"118","DOI":"10.1159\/000381804","article-title":"Kinect-based five-times-sit-to-stand test for clinical and in-home assessment of fall risk in older people","volume":"62","author":"Ejupi A","year":"2015","unstructured":"Ejupi A, Brodie M, Gschwind YJ, Lord SR, Zagler WL, Delbaere K. Kinect-based five-times-sit-to-stand test for clinical and in-home assessment of fall risk in older people. Gerontology. 2015;62(1):118\u2013124.10.1159\/00038180426021781"},{"issue":"4","key":"r36","series-title":"Neurospine","doi-asserted-by":"publisher","first-page":"654","DOI":"10.14245\/ns.1938434.217","article-title":"Data mining in spine surgery: leveraging electronic health records for machine learning and clinical research","volume":"16","author":"Staartjes VE","year":"2019","unstructured":"Staartjes VE, Stienen MN. Data mining in spine surgery: leveraging electronic health records for machine learning and clinical research. Neurospine. 2019;16(4):654\u2013656.3190545310.14245\/ns.1938434.217"},{"key":"r1","series-title":"World Neurosurg","doi-asserted-by":"publisher","first-page":"328","DOI":"10.1016\/j.wneu.2017.09.002","article-title":"Current status of worldwide use of Patient-Reported Outcome Measures (PROMs) in spine care","volume":"108","author":"Falavigna A","year":"2017","unstructured":"Falavigna A, Dozza DC, Teles AR, Wong CC, Barbagallo G, Brodke D, Current status of worldwide use of Patient-Reported Outcome Measures (PROMs) in spine care. World Neurosurg. 2017;108:328\u2013335.2889369310.1016\/j.wneu.2017.09.002"},{"issue":"5","key":"r2","series-title":"J Neurosurg","doi-asserted-by":"publisher","first-page":"947","DOI":"10.3171\/2012.7.JNS111622","article-title":"Measuring surgical outcomes in neurosurgery: implementation, analysis, and auditing a prospective series of more than 5000 procedures","volume":"117","author":"Theodosopoulos PV","year":"2012","unstructured":"Theodosopoulos PV, Ringer AJ, McPherson CM, Warnick RE, Kuntz C IV, Zuccarello M, Tew JM Jr. Measuring surgical outcomes in neurosurgery: implementation, analysis, and auditing a prospective series of more than 5000 procedures. J Neurosurg. 2012;117(5):947\u2013954.10.3171\/2012.7.JNS11162222880719"},{"issue":"2","key":"r3","series-title":"Neurosurg Clin N Am","doi-asserted-by":"publisher","first-page":"P265","DOI":"10.1016\/j.nec.2014.11.013","article-title":"Measuring outcomes for neurosurgical procedures","volume":"26","author":"Theodosopoulos PV","year":"2015","unstructured":"Theodosopoulos PV, Ringer AJ. Measuring outcomes for neurosurgical procedures. Neurosurg Clin N Am. 2015;26(2):P265\u2013P269.10.1016\/j.nec.2014.11.013"},{"issue":"3","key":"r4","series-title":"Neurooncol Pract","first-page":"226","article-title":"Quality improvement of neuro-oncology services: integrating the routine collection of patient-reported, health-related quality-of-life measures","volume":"6","author":"Fern\u00e1ndez-M\u00e9ndez R","year":"2019","unstructured":"Fern\u00e1ndez-M\u00e9ndez R, Rastall RJ, Sage WA, Oberg I, Bullen G, Charge AL, Quality improvement of neuro-oncology services: integrating the routine collection of patient-reported, health-related quality-of-life measures. Neurooncol Pract. 2019;6(3):226\u2013236.31385996"},{"issue":"1","key":"r5","series-title":"Neurosurg Focus","doi-asserted-by":"publisher","first-page":"E2","DOI":"10.3171\/2012.10.FOCUS12311","article-title":"The National Neurosurgery Quality and Outcomes Database and NeuroPoint Alliance: rationale, development, and implementation","volume":"34","author":"Asher AL","year":"2013","unstructured":"Asher AL, McCormick PC, Selden NR, Ghogawala Z, McGirt MJ. The National Neurosurgery Quality and Outcomes Database and NeuroPoint Alliance: rationale, development, and implementation. Neurosurg Focus. 2013;34(1):E2.2327826310.3171\/2012.10.FOCUS12311"},{"issue":"4","key":"r6","series-title":"J Neurosurg Anesthesiol","doi-asserted-by":"publisher","first-page":"328","DOI":"10.1097\/ANA.0000000000000474","article-title":"Safety outcomes following spine and cranial neurosurgery: evidence from the National Surgical Quality Improvement Program","volume":"30","author":"Rock AK","year":"2018","unstructured":"Rock AK, Opalak CF, Workman KG, Broaddus WC. Safety outcomes following spine and cranial neurosurgery: evidence from the National Surgical Quality Improvement Program. J Neurosurg Anesthesiol. 2018;30(4):328\u2013336.2913570010.1097\/ANA.0000000000000474"},{"issue":"7","key":"r7","series-title":"Spine J","doi-asserted-by":"publisher","first-page":"1276","DOI":"10.1016\/j.spinee.2019.02.014","article-title":"Objective measures of functional impairment for degenerative diseases of the lumbar spine: a systematic review of the literature","volume":"19","author":"Stienen MN","year":"2019","unstructured":"Stienen MN, Ho AL, Staartjes VE, Maldaner N, Veeravagu A, Desai A, Objective measures of functional impairment for degenerative diseases of the lumbar spine: a systematic review of the literature. Spine J. 2019;19(7):1276\u20131293.3083131610.1016\/j.spinee.2019.02.014"},{"issue":"4","key":"r8","series-title":"J Neurosurg Spine","doi-asserted-by":"publisher","first-page":"380","DOI":"10.3171\/2018.2.SPINE171416","article-title":"The five-repetition sit-to-stand test: evaluation of a simple and objective tool for the assessment of degenerative pathologies of the lumbar spine","volume":"29","author":"Staartjes VE","year":"2018","unstructured":"Staartjes VE, Schr\u00f6der ML. The five-repetition sit-to-stand test: evaluation of a simple and objective tool for the assessment of degenerative pathologies of the lumbar spine. J Neurosurg Spine. 2018;29(4):380\u2013387.2995714710.3171\/2018.2.SPINE171416"},{"issue":"4","key":"r9","series-title":"Eur Spine J","doi-asserted-by":"publisher","first-page":"665","DOI":"10.1007\/s00586-019-05897-3","article-title":"Can objective functional impairment in lumbar degenerative disease be reliably assessed at home using the five-repetition sit-to-stand test? A prospective study","volume":"28","author":"Staartjes VE","year":"2019","unstructured":"Staartjes VE, Beusekamp F, Schr\u00f6der ML. Can objective functional impairment in lumbar degenerative disease be reliably assessed at home using the five-repetition sit-to-stand test? A prospective study. Eur Spine J. 2019;28(4):665\u2013673.10.1007\/s00586-019-05897-3"},{"issue":"22","key":"r10","series-title":"Spine (Phila Pa 1976)","doi-asserted-by":"publisher","first-page":"2412","DOI":"10.1097\/00007632-199811150-00011","article-title":"Psychometric characteristics and clinical usefulness of physical performance tests in patients with low back pain","volume":"23","author":"Simmonds MJ","year":"1998","unstructured":"Simmonds MJ, Olson SL, Jones S, Hussein T, Lee CE, Novy D, Radwan H. Psychometric characteristics and clinical usefulness of physical performance tests in patients with low back pain. Spine (Phila Pa 1976). 1998;23(22):2412\u20132421.10.1097\/00007632-199811150-00011"},{"issue":"1","key":"r11","series-title":"Physiother Theory Pract","doi-asserted-by":"publisher","first-page":"49","DOI":"10.3109\/09593980802602844","article-title":"Use of physical performance tests in a group of Brazilian Portuguese-speaking individuals with low back pain","volume":"26","author":"Teixeira da Cunha-Filho I","year":"2010","unstructured":"Teixeira da Cunha-Filho I, Lima FC, Guimar\u00e3es 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\u201355.10.3109\/09593980802602844"},{"issue":"1","key":"r12","series-title":"J Neurosurg Spine","doi-asserted-by":"publisher","first-page":"4","DOI":"10.3171\/2019.12.SPINE191124","article-title":"Objective functional impairment in lumbar degenerative disease: concurrent validity of the baseline severity stratification for the five-repetition sit-to-stand test","volume":"33","author":"Klukowska AM","year":"2020","unstructured":"Klukowska AM, Schr\u00f6der ML, Stienen MN, Staartjes VE. Objective functional impairment in lumbar degenerative disease: concurrent validity of the baseline severity stratification for the five-repetition sit-to-stand test. J Neurosurg Spine. 2020;33(1):4\u201311.10.3171\/2019.12.SPINE191124"},{"key":"r13","series-title":"BioMed Res Int","doi-asserted-by":"publisher","first-page":"642362","DOI":"10.1155\/2013\/642362","article-title":"Association of seat height and arm position on the five times sit-to-stand test times of stroke survivors","volume":"2013","author":"Ng SSM","year":"2013","unstructured":"Ng SSM, Cheung SY, Lai LSW, Liu ASL, Ieong SHI, Fong SSM. Association of seat height and arm position on the five times sit-to-stand test times of stroke survivors. BioMed Res Int. 2013;2013:642362.2410671110.1155\/2013\/642362"},{"issue":"3","key":"r14","series-title":"J Rehabil Med","doi-asserted-by":"publisher","first-page":"262","DOI":"10.2340\/16501977-1915","article-title":"Five Times Sit-To-Stand test completion times among older women: influence of seat height and arm position","volume":"47","author":"Ng SSM","year":"2015","unstructured":"Ng SSM, Cheung SY, Lai LSW, Liu ASL, Ieong SHI, Fong SSM. Five Times Sit-To-Stand test completion times among older women: influence of seat height and arm position. J Rehabil Med. 2015;47(3):262\u2013266.2543714210.2340\/16501977-1915"},{"issue":"5","key":"r15","series-title":"J Neurosurg Spine","doi-asserted-by":"publisher","first-page":"598","DOI":"10.3171\/2016.11.SPINE16683","article-title":"Validation of the baseline severity stratification of objective functional impairment in lumbar degenerative disc disease","volume":"26","author":"Stienen MN","year":"2017","unstructured":"Stienen MN, Smoll NR, Joswig H, Corniola MV, Schaller K, Hildebrandt G, Gautschi OP. Validation of the baseline severity stratification of objective functional impairment in lumbar degenerative disc disease. J Neurosurg Spine. 2017;26(5):598\u2013604.10.3171\/2016.11.SPINE1668328291406"},{"issue":"2","key":"r16","series-title":"Neurosurgery","doi-asserted-by":"publisher","first-page":"270","DOI":"10.1227\/NEU.0000000000001195","article-title":"Validity and reliability of a measurement of objective functional impairment in lumbar degenerative disc disease: the Timed Up and Go (TUG) test","volume":"79","author":"Gautschi OP","year":"2016","unstructured":"Gautschi OP, Smoll NR, Corniola MV, Joswig H, Chau I, Hildebrandt G, 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\u2013278.2670284010.1227\/NEU.0000000000001195"},{"issue":"13","key":"r17","series-title":"N Engl J Med","doi-asserted-by":"publisher","first-page":"1216","DOI":"10.1056\/NEJMp1606181","article-title":"Predicting the future - big data, machine learning, and clinical medicine","volume":"375","author":"Obermeyer Z","year":"2016","unstructured":"Obermeyer Z, Emanuel EJ. Predicting the future - big data, machine learning, and clinical medicine. N Engl J Med. 2016;375(13):1216\u20131219.10.1056\/NEJMp160618127682033"},{"issue":"7624","key":"r18","series-title":"BMJ","doi-asserted-by":"publisher","first-page":"806","DOI":"10.1136\/bmj.39335.541782.AD","article-title":"Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement: guidelines for reporting observational studies","volume":"335","author":"von Elm E","year":"2007","unstructured":"von Elm E, Altman DG, Egger M, Pocock SJ, G\u00f8tzsche PC, Vandenbroucke JP. Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement: guidelines for reporting observational studies. BMJ. 2007;335(7624):806\u2013808.10.1136\/bmj.39335.541782.AD17947786"},{"issue":"11","key":"r19","series-title":"Thorax","doi-asserted-by":"publisher","first-page":"1015","DOI":"10.1136\/thoraxjnl-2013-203576","article-title":"The five-repetition sit-to-stand test as a functional outcome measure in COPD","volume":"68","author":"Jones SE","year":"2013","unstructured":"Jones SE, Kon SSC, Canavan JL, Patel MS, Clark AL, Nolan CM, The five-repetition sit-to-stand test as a functional outcome measure in COPD. Thorax. 2013;68(11):1015\u20131020.2378337210.1136\/thoraxjnl-2013-203576"},{"key":"r20","series-title":"R: A Language and Environment for Statistical Computing","author":"R Core Team","year":"2021","unstructured":"R Core Team. R: A Language and Environment for Statistical Computing. R Foundation for Statistical Computing; 2021. Accessed September 9, 2021. https:\/\/www.R-project.org\/"},{"key":"r21","series-title":"J Stat Softw","doi-asserted-by":"publisher","first-page":"i07","DOI":"10.18637\/jss.v074.i07","article-title":"Imputation with the R package VIM","volume":"74","author":"Kowarik A","year":"2016","unstructured":"Kowarik A, Templ M. Imputation with the R package VIM. J Stat Softw. 2016;74:i07.10.18637\/jss.v074.i07"},{"key":"r22","series-title":"Handbook of Quantile Regression","doi-asserted-by":"publisher","DOI":"10.1201\/9781315120256","author":"Koenker R","year":"2017","unstructured":"Koenker R, Chernozhukov V, He X, Peng L. Handbook of Quantile Regression. CRC Press; 2017.10.1201\/9781315120256"},{"key":"r23","series-title":"R-project.org","article-title":"quantreg: Quantile regression","author":"Koenker R","unstructured":"Koenker R, Portnoy S, Ng PT, Melly B, Zeilis A, Grosjean P, quantreg: Quantile regression. R-project.org. Accessed September 9, 2021. https:\/\/CRAN.R-project.org\/package=quantreg"},{"issue":"8476","key":"r24","series-title":"Lancet","doi-asserted-by":"publisher","first-page":"307","DOI":"10.1016\/S0140-6736(86)90837-8","article-title":"Statistical methods for assessing agreement between two methods of clinical measurement","volume":"1","author":"Bland JM","year":"1986","unstructured":"Bland JM, Altman DG. Statistical methods for assessing agreement between two methods of clinical measurement. Lancet. 1986;1(8476):307\u2013310.286817210.1016\/S0140-6736(86)90837-8"},{"key":"r25","article-title":"Mosby\u2019s Diagnostic and Laboratory Test Reference","author":"Pagana KD","year":"2018","unstructured":"Pagana KD, Pagana TJ, Pagana TN. Mosby\u2019s Diagnostic and Laboratory Test Reference. Elsevier Health Sciences; 2018."},{"issue":"7","key":"r26","series-title":"J Clin Epidemiol","doi-asserted-by":"publisher","first-page":"737","DOI":"10.1016\/j.jclinepi.2010.02.006","article-title":"The COSMIN study reached international consensus on taxonomy, terminology, and definitions of measurement properties for health-related patient-reported outcomes","volume":"63","author":"Mokkink LB","year":"2010","unstructured":"Mokkink LB, Terwee CB, Patrick DL, Alonso J, Stratford PW, Knol DL, 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\u2013745.2049480410.1016\/j.jclinepi.2010.02.006"},{"issue":"5","key":"r27","series-title":"Neurosurg Rev","doi-asserted-by":"publisher","first-page":"1331","DOI":"10.1007\/s10143-019-01168-3","article-title":"Association of maximum back and leg pain severity with objective functional impairment as assessed by five-repetition sit-to-stand testing: analysis of two prospective studies","volume":"43","author":"Staartjes VE","year":"2020","unstructured":"Staartjes VE, Klukowska AM, Schr\u00f6der ML. Association of maximum back and leg pain severity with objective functional impairment as assessed by five-repetition sit-to-stand testing: analysis of two prospective studies. Neurosurg Rev. 2020;43(5):1331\u20131338.10.1007\/s10143-019-01168-331451936"},{"issue":"1-2","key":"r28","series-title":"Pain","doi-asserted-by":"publisher","first-page":"103","DOI":"10.1016\/j.pain.2006.08.011","article-title":"Impact of low back pain on functional limitations, depressed mood and quality of life in patients with rheumatoid arthritis","volume":"127","author":"Kothe R","year":"2007","unstructured":"Kothe R, Kohlmann T, Klink T, R\u00fcther W, Klinger R. Impact of low back pain on functional limitations, depressed mood and quality of life in patients with rheumatoid arthritis. Pain. 2007;127(1-2):103\u2013108.10.1016\/j.pain.2006.08.01116982148"},{"issue":"9178","key":"r29","series-title":"Lancet","doi-asserted-by":"publisher","first-page":"581","DOI":"10.1016\/S0140-6736(99)01312-4","article-title":"Epidemiological features of chronic low-back pain","volume":"354","author":"Andersson GB","year":"1999","unstructured":"Andersson GB. Epidemiological features of chronic low-back pain. Lancet. 1999;354(9178):581\u2013585.1047071610.1016\/S0140-6736(99)01312-4"},{"issue":"10","key":"r30","series-title":"J Gerontol A Biol Sci Med Sci","doi-asserted-by":"publisher","first-page":"M487","DOI":"10.1093\/gerona\/54.10.M487","article-title":"Low back pain and disability in older women: independent association with difficulty but not inability to perform daily activities","volume":"54","author":"Leveille SG","year":"1999","unstructured":"Leveille SG, Guralnik JM, Hochberg M, Hirsch R, Ferrucci L, Langlois J, Low back pain and disability in older women: independent association with difficulty but not inability to perform daily activities. J Gerontol A Biol Sci Med Sci. 1999;54(10):M487\u2013M493.10.1093\/gerona\/54.10.M487"},{"issue":"20","key":"r31","series-title":"Circulation","doi-asserted-by":"publisher","first-page":"1920","DOI":"10.1161\/CIRCULATIONAHA.115.001593","article-title":"Machine learning in medicine","volume":"132","author":"Deo RC","year":"2015","unstructured":"Deo RC. Machine learning in medicine. Circulation. 2015;132(20):1920\u20131930.10.1161\/CIRCULATIONAHA.115.001593"},{"issue":"14","key":"r32","series-title":"N Engl J Med","doi-asserted-by":"publisher","first-page":"1347","DOI":"10.1056\/NEJMra1814259","article-title":"Machine learning in medicine","volume":"380","author":"Rajkomar A","year":"2019","unstructured":"Rajkomar A, Dean J, Kohane I. Machine learning in medicine. N Engl J Med. 2019;380(14):1347\u20131358.10.1056\/NEJMra1814259"},{"issue":"1","key":"r33","series-title":"Nat Med","doi-asserted-by":"publisher","first-page":"44","DOI":"10.1038\/s41591-018-0300-7","article-title":"High-performance medicine: the convergence of human and artificial intelligence","volume":"25","author":"Topol EJ","year":"2019","unstructured":"Topol EJ. High-performance medicine: the convergence of human and artificial intelligence. Nat Med. 2019;25(1):44\u201356.3061733910.1038\/s41591-018-0300-7"},{"issue":"11","key":"r34","series-title":"JAMA","doi-asserted-by":"publisher","first-page":"1117","DOI":"10.1001\/jama.2014.2135","article-title":"Age-adjusted D-dimer cutoff levels to rule out pulmonary embolism: the ADJUST-PE study","volume":"311","author":"Righini M","year":"2014","unstructured":"Righini M, Van Es J, Den Exter PL, Roy PM, Verschuren F, Ghuysen A, Age-adjusted D-dimer cutoff levels to rule out pulmonary embolism: the ADJUST-PE study. JAMA. 2014;311(11):1117\u20131124.2464360110.1001\/jama.2014.2135"},{"issue":"1","key":"r35","series-title":"Gerontology","doi-asserted-by":"publisher","first-page":"118","DOI":"10.1159\/000381804","article-title":"Kinect-based five-times-sit-to-stand test for clinical and in-home assessment of fall risk in older people","volume":"62","author":"Ejupi A","year":"2015","unstructured":"Ejupi A, Brodie M, Gschwind YJ, Lord SR, Zagler WL, Delbaere K. Kinect-based five-times-sit-to-stand test for clinical and in-home assessment of fall risk in older people. Gerontology. 2015;62(1):118\u2013124.10.1159\/00038180426021781"},{"issue":"4","key":"r36","series-title":"Neurospine","doi-asserted-by":"publisher","first-page":"654","DOI":"10.14245\/ns.1938434.217","article-title":"Data mining in spine surgery: leveraging electronic health records for machine learning and clinical research","volume":"16","author":"Staartjes VE","year":"2019","unstructured":"Staartjes VE, Stienen MN. Data mining in spine surgery: leveraging electronic health records for machine learning and clinical research. Neurospine. 2019;16(4):654\u2013656.3190545310.14245\/ns.1938434.217"}],"container-title":["Neurosurgical Focus"],"original-title":[],"link":[{"URL":"https:\/\/thejns.org\/view\/journals\/neurosurg-focus\/51\/5\/article-pE8.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/thejns.org\/downloadpdf\/journals\/neurosurg-focus\/51\/5\/article-pE8.xml","content-type":"text\/html","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/thejns.org\/downloadpdf\/journals\/neurosurg-focus\/51\/5\/article-pE8.xml","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,6]],"date-time":"2026-06-06T08:26:04Z","timestamp":1780734364000},"score":1,"resource":{"primary":{"URL":"https:\/\/thejns.org\/view\/journals\/neurosurg-focus\/51\/5\/article-pE8.xml"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,11]]},"references-count":72,"journal-issue":{"issue":"5"},"URL":"https:\/\/doi.org\/10.3171\/2021.8.focus21386","relation":{},"ISSN":["1092-0684"],"issn-type":[{"value":"1092-0684","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,11]]}}}