Statistical Significance Versus Clinical Importance: Trials on Exercise Therapy for Chronic Low Back Pain as Example

Study Design. Critical appraisal of the literature. Objecives. The objective of this study was to assess if results of back pain trials are statistically significant and clinically important. Summary of Background Data. There seems to be a discrepancy between conclusions reported by authors and actual results of randomized controlled trials. Little attention has been paid to the problem of over-reporting of conclusions. Methods. All 43 trials of the Cochrane review on exercise therapy for low back pain were included. Descriptive analyses were conducted. Results. Eighteen trials reported positive conclusions in favor of exercise. Only six of the 43 studies showed both clinically important and statistically significant differences in favor of the exercise groups on function, and 4 on pain. Conclusion. It seems that many conclusions of studies of exercise therapy for chronic low back pain have been based on statistical significance of results rather than on clinical importance and, consequently, may have been too positive. Authors of trials should report not only statistical significance of results but also clinical importance.

[1]  R A Deyo,et al.  A controlled trial of transcutaneous electrical nerve stimulation (TENS) and exercise for chronic low back pain. , 1990, The New England journal of medicine.

[2]  J. Farrar,et al.  Clinical importance of changes in chronic pain intensity measured on an 11-point numerical pain rating scale , 2001, PAIN.

[3]  W. Wajanavisit,et al.  The efficacy of an aerobic exercise and health education program for treatment of chronic low back pain. , 2001, Journal of the Medical Association of Thailand = Chotmaihet thangphaet.

[4]  B. Koes,et al.  Meta-Analysis: Exercise Therapy for Nonspecific Low Back Pain , 2005, Annals of Internal Medicine.

[5]  S. Keinänen-Kiukaanniemi,et al.  Does folk medicine work? A randomized clinical trial on patients with prolonged back pain. , 1997, Archives of physical medicine and rehabilitation.

[6]  L. Nilsson-Wikmar,et al.  Stabilizing training compared with manual treatment in sub-acute and chronic low-back pain. , 2003, Manual therapy.

[7]  J. Fritz,et al.  A comparison of a modified Oswestry Low Back Pain Disability Questionnaire and the Quebec Back Pain Disability Scale. , 2001, Physical therapy.

[8]  E. Mälkiä,et al.  An experimental controlled study on postural sway and therapeutic exercise in subjects with low back pain , 2000, Clinical rehabilitation.

[9]  F. Lindgärde,et al.  The Effect of Dynamic Strength Back Exercise and/or a Home Training Program in 57-year-old Women With Chronic Low Back Pain: Results of a Prospective Randomized Study With a 3-Year Follow-Up Period , 1997, Spine.

[10]  A. Mannion,et al.  A randomized clinical trial of three active therapies for chronic low back pain. , 1999, Spine.

[11]  C. Ekdahl,et al.  The effect of McKenzie therapy as compared with that of intensive strengthening training for the treatment of patients with subacute or chronic low back pain: A randomized controlled trial. , 2002, Spine.

[12]  K. Nas,et al.  Efficacy of low power laser therapy and exercise on pain and functions in chronic low back pain , 2003, Lasers in surgery and medicine.

[13]  S. Goodman Toward Evidence-Based Medical Statistics. 1: The P Value Fallacy , 1999, Annals of Internal Medicine.

[14]  C. Dugas,et al.  Evaluation of a specific home exercise program for low back pain. , 2002, Journal of manipulative and physiological therapeutics.

[15]  Zylbergold Rs,et al.  Lumbar disc disease: comparative analysis of physical therapy treatments. , 1981 .

[16]  S. van Buuren,et al.  [Cesar therapy is temporarily more effective in patients with chronic low back pain than the standard treatment by family practitioner: randomized, controlled and blinded clinical trial with 1 year follow-up]. , 2000, Nederlands tijdschrift voor geneeskunde.

[17]  Pekka Rissanen,et al.  A Randomized Trial of Combined Manipulation, Stabilizing Exercises, and Physician Consultation Compared to Physician Consultation Alone for Chronic Low Back Pain , 2003, Spine.

[18]  P. Glasziou,et al.  Prolotherapy Injections, Saline Injections, and Exercises for Chronic Low-Back Pain: A Randomized Trial , 2004, Spine.

[19]  R. S. Zylbergold,et al.  Lumbar disc disease: comparative analysis of physical therapy treatments. , 1981, Archives of physical medicine and rehabilitation.

[20]  P. Skov,et al.  Intensive, Dynamic Back-Muscle Exercises, Conventional Physiotherapy, or Placebo-Control Treatment of Low-Back Pain: A Randomized, Observer-Blind Trial , 1993, Spine.

[21]  A. Ljunggren,et al.  Efficiency and Costs of Medical Exercise Therapy, Conventional Physiotherapy, and Self‐Exercise in Patients With Chronic Low Back Pain: A Pragmatic, Randomized, Single‐Blinded, Controlled Trial With 1‐Year Follow‐Up , 1998, Spine.

[22]  T. Bendix,et al.  Active treatment programs for patients with chronic low back pain: a prospective, randomized, observer-blinded study , 2004, European Spine Journal.

[23]  O. Airaksinen,et al.  The efficacy of active rehabilitation in chronic low back pain. Effect on pain intensity, self-experienced disability, and lumbar fatigability. , 1999, Spine.

[24]  Jennifer L Keating,et al.  A comparison of five low back disability questionnaires: reliability and responsiveness. , 2002, Physical therapy.

[25]  S. Dalichau,et al.  Auswirkungen elastischer Lumbal-Stützgurte auf den Effekt eines Muskeltrainingsprogrammes für Patienten mit chronischen Rückenschmerzen , 2000 .

[26]  A. Nordwall,et al.  The clinical importance of changes in outcome scores after treatment for chronic low back pain , 2003, European Spine Journal.

[27]  Eva Lundberg,et al.  CLINICAL TRIAL OF INTENSIVE MUSCLE TRAINING FOR CHRONIC LOW BACK PAIN , 1988, The Lancet.

[28]  A. Beurskens,et al.  Responsiveness of functional status in low back pain: a comparison of different instruments , 1996, Pain.

[29]  S. Dalichau,et al.  [Effects of elastic lumbar belts on the effect of a muscle training program for patients with chronic back pain]. , 2000, Zeitschrift fur Orthopadie und ihre Grenzgebiete.

[30]  J. Turner,et al.  Effectiveness of behavioral therapy for chronic low back pain: a component analysis. , 1990, Journal of consulting and clinical psychology.

[31]  A. Lidström,et al.  Physical therapy on low back pain and sciatica. An attempt at evaluation. , 2019, Scandinavian journal of rehabilitation medicine.

[32]  M. Preyde Effectiveness of massage therapy for subacute low-back pain: a randomized controlled trial. , 2000, CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne.

[33]  N. Yozbatiran,et al.  Effects of fitness and aquafitness exercises on physical fitness in patients with chronic low back pain , 2004 .

[34]  Lorimer Moseley,et al.  Combined physiotherapy and education is efficacious for chronic low back pain. , 2002, The Australian journal of physiotherapy.

[35]  T. Bendix,et al.  Functional Restoration versus Outpatient Physical Training in Chronic Low Back Pain: A Randomized Comparative Study , 2000, Spine.

[36]  G H Guyatt,et al.  Sensitivity to change of the Roland-Morris Back Pain Questionnaire: part 1. , 1998, Physical therapy.

[37]  Bengt J Allen,et al.  Statistics: Concepts and Applications for Science.ByDavid LeBlanc.Sudbury (Massachusetts): Jones and Bartlett Publishers. $89.95 (two‐volume set). xvii + 382 p; ill.; index. ISBN: 0–7637–4699–1. 2004.Workbook to AccompanyStatistics: Concepts and Applications for Science.ByDavid LeBlanc.Sudbury (Mass , 2004 .

[38]  D. Chow,et al.  The use of electro-acupuncture in conjunction with exercise for the treatment of chronic low-back pain. , 2003, Journal of alternative and complementary medicine.

[39]  K. Bø,et al.  Active back school: prophylactic management for low back pain. A randomized, controlled, 1-year follow-up study. , 1999, Spine.

[40]  R. Donelson,et al.  Effects of spinal flexion and extension exercises on low-back pain and spinal mobility in chronic mechanical low-back pain patients. , 1992, Spine.

[41]  C. Goldsmith,et al.  Trunk exercise combined with spinal manipulative or NSAID therapy for chronic low back pain: a randomized, observer-blinded clinical trial. , 1996, Journal of manipulative and physiological therapeutics.

[42]  D. Felsenberg,et al.  Treatment of Chronic Lower Back Pain with Lumbar Extension and Whole-Body Vibration Exercise: A Randomized Controlled Trial , 2002, Spine.

[43]  I. Richard,et al.  Effects of Functional Restoration Versus 3 Hours per Week Physical Therapy: A Randomized Controlled Study , 2004, Spine.

[44]  N. M. Alexandre,et al.  Evaluation of a program to reduce back pain in nursing personnel. , 2001, Revista de saude publica.

[45]  D. Beaton,et al.  Many faces of the minimal clinically important difference (MCID): a literature review and directions for future research. , 2002, Current opinion in rheumatology.

[46]  H. Lie,et al.  [Mobilizing or stabilizing exercise in degenerative disk disease in the lumbar region?]. , 1999, Tidsskrift for den Norske laegeforening : tidsskrift for praktisk medicin, ny raekke.

[47]  P. Stratford,et al.  Sensitivity to change of the Roland-Morris Back Pain Questionnaire: part 2. , 1998, Physical therapy.

[48]  M. Pollock,et al.  Lumbar Strengthening in Chronic Low Back Pain Patients|Physiologic and Psychological Benefits , 1993, Spine.

[49]  S. Pocock,et al.  Statistical problems in the reporting of clinical trials. A survey of three medical journals. , 1987, The New England journal of medicine.

[50]  J. Fairbank,et al.  Randomised controlled trial for evaluation of fitness programme for patients with chronic low back pain , 1995, BMJ.

[51]  H. Doll,et al.  Randomized Controlled Trial of Physiotherapy Compared to Advice for Low Back Pain , 2005 .

[52]  Henrica C W de Vet,et al.  Minimal Clinically Important Change for Pain Intensity, Functional Status, and General Health Status in Patients With Nonspecific Low Back Pain , 2006, Spine.

[53]  J. Farrar,et al.  The impact of modified Hatha yoga on chronic low back pain: a pilot study. , 2004, Alternative therapies in health and medicine.

[54]  R A Deyo,et al.  Outcome Measures for Low Back Pain Research: A Proposal for Standardized Use , 1998, Spine.

[55]  A Laupacis,et al.  How well is the clinical importance of study results reported? An assessment of randomized controlled trials. , 2001, CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne.

[56]  Douglas G. Altman,et al.  The CONSORT statement: revised recommendations for improving the quality of reports of parallel-group randomised trials , 2001, The Lancet.

[57]  H. Doll,et al.  Randomised controlled trial of physiotherapy compared with advice for low back pain , 2005 .

[58]  S. Warming,et al.  Exercises for chronic low back pain: a clinical trial. , 1995, The Journal of orthopaedic and sports physical therapy.

[59]  V. Mooney Manual therapy and exercise therapy in patients with chronic low back pain: a randomized, controlled trial with 1-year follow-up. , 2004, Spine.

[60]  K. Bø,et al.  The effect of a Mensendieck exercise program as secondary prophylaxis for recurrent low back pain. A randomized, controlled trial with 12-month follow-up. , 1999, Spine.