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  • Determining the Minimally Clinical Important Difference(MCID) in Pain, Quality of Life and Disability for Spinal Cord Stimulation for Failed Neck and Failed Back Syndromes

    Final Number:

    Alexandra Rose Paul; Vignessh Kumar; Steven G Roth MS; M. Reid Gooch MD; Julie G. Pilitsis MD, PhD

    Study Design:

    Subject Category:

    Meeting: Congress of Neurological Surgeons 2015 Annual Meeting

    Introduction: With rising health care costs, clinical outcome data is becoming increasingly important. The concept of minimally clinical important difference(MCID) has been shown to be effective in spine surgery to differentiate between clinically insignificant and significant improvements and to measure the patient’s perspective of quality of life and disability. We sought to determine the MCID for spinal cord stimulation(SCS) therapy for failed neck and back syndromes, which has not been established to date.

    Methods: Preoperative and 6 month outcomes were assessed prospectively, including the ODI, BDI and VAS questionnaires. Patients were asked by a blind investigator:(1)are they satisfied with SCS therapy and (2)would they have the surgery again? Four methods of calculating the MCID were utilized, including the average change approach, the minimum detectable change approach, the change difference and the receiver operating characteristic approach.

    Results: Forty eight patients who underwent SCS placement from 2012-2014 were prospectively reviewed. Thirty five(73%) patients stated they were satisfied with SCS therapy and they would have the surgery again. Satisfied patients had an average improvement of 2.9 points on the VAS and 11.5 points on the ODI at 6 months compared to an average decline of 0.78 points on the VAS and 1.8 points on ODI in the patients who were not satisfied with SCS therapy(p=0.005, p=0.06). The 4 calculation methods yielded a range of outcome scores(ODI 8.2-13.3, BDI 3.2-7, McGill 0.3-1.3 and VAS 1.2-3.7).

    Conclusions: The MCID for SCS placement was calculated using 4 methods. The results are similar to calculations for the MCID for traditional surgical procedures done for pain. Our results suggest that an improvement of 1.2-3.7 points on the VAS scale and 8.2-13.3 points on the ODI is clinically meaningful to the patient. Further defining the MCID for SCS therapy will remain of utmost importance in order to justify the cost of the procedure.

    Patient Care: Determining the MCID for SCS therapy will allow for an objective measurement of patient's perception of improvement and allow a determination of what is clinically significant for patients.

    Learning Objectives: By conclusion of this session, participants should be able to: 1) Describe the importance of MCID in surgeries with subjective outcome 2) Compare the MCID for spinal cord stimulation for failed neck and failed back syndromes compared to the MCID for other common lumbar and cervical procedures.

    References: 1.Testa MA. Interpretation of quality-of-life outcomes: issues that affect magnitude and meaning. Medical care. Sep 2000;38(9 Suppl):II166-174. 2.Carver RP. The Case against Statistical Significance Testing, Revisited. J Exp Educ. Sum 1993;61(4):287-292. 3.Jacobson NS, Truax P. Clinical significance: a statistical approach to defining meaningful change in psychotherapy research. Journal of consulting and clinical psychology. Feb 1991;59(1):12-19. 4.Sterne JA, Davey Smith G. Sifting the evidence-what's wrong with significance tests? Bmj. Jan 27 2001;322(7280):226-231. 5.Lieberman MD, Cunningham WA. Type I and Type II error concerns in fMRI research: re-balancing the scale. Social cognitive and affective neuroscience. Dec 2009;4(4):423-428. 6.Hanley JA, Mcneil BJ. The Meaning and Use of the Area under a Receiver Operating Characteristic (Roc) Curve. Radiology. 1982;143(1):29-36. 7.Jaeschke R, Singer J, Guyatt GH. Measurement of health status. Ascertaining the minimal clinically important difference. Controlled clinical trials. Dec 1989;10(4):407-415. 8.McGlothlin AE, Lewis RJ. Minimal Clinically Important Difference Defining What Really Matters to Patients. Jama-J Am Med Assoc. Oct 1 2014;312(13):1342-1343. 9.Copay AG, Subach BR, Glassman SD, Polly DW, Jr., Schuler TC. Understanding the minimum clinically important difference: a review of concepts and methods. The spine journal : official journal of the North American Spine Society. Sep-Oct 2007;7(5):541-546. 10.Bellamy N, Carette S, Ford PM, et al. Osteoarthritis antirheumatic drug trials. III. Setting the delta for clinical trials--results of a consensus development (Delphi) exercise. The Journal of rheumatology. Mar 1992;19(3):451-457. 11.Tubach F, Ravaud P, Baron G, et al. Evaluation of clinically relevant changes in patient reported outcomes in knee and hip osteoarthritis: the minimal clinically important improvement. Annals of the rheumatic diseases. Jan 2005;64(1):29-33. 12.Carragee EJ, Cheng I. Minimum acceptable outcomes after lumbar spinal fusion. The spine journal : official journal of the North American Spine Society. Apr 2010;10(4):313-320. 13.Copay AG, Glassman SD, Subach BR, Berven S, Schuler TC, Carreon LY. Minimum clinically important difference in lumbar spine surgery patients: a choice of methods using the Oswestry Disability Index, Medical Outcomes Study questionnaire Short Form 36, and pain scales. The spine journal : official journal of the North American Spine Society. Nov-Dec 2008;8(6):968-974. 14.Mannion AF, Porchet F, Kleinstuck FS, et al. The quality of spine surgery from the patient's perspective: part 2. Minimal clinically important difference for improvement and deterioration as measured with the Core Outcome Measures Index. European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society. Aug 2009;18 Suppl 3:374-379. 15.Gatchel RJ, Lurie JD, Mayer TG. Minimal clinically important difference. Spine. Sep 1 2010;35(19):1739-1743. 16.Beaton DE, Boers M, Wells GA. Many faces of the minimal clinically important difference (MCID): a literature review and directions for future research. Current opinion in rheumatology. Mar 2002;14(2):109-114. 17.Kunnumpurath S, Srinivasagopalan R, Vadivelu N. Spinal cord stimulation: principles of past, present and future practice: a review. Journal of clinical monitoring and computing. Oct 2009;23(5):333-339.

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