Evidence-based medicine, systematic reviews, and guidelines in interventional pain management, part I: introduction and general considerations.

Evidence-based medicine, systematic reviews, and guidelines are part of modern interventional pain management. As in other specialties in the United States, evidence-based medicine appears to motivate the search for answers to numerous questions related to costs and quality of health care as well as access to care. Scientific, relevant evidence is essential in clinical care, policy-making, dispute resolution, and law. Consequently, evidence based practice brings together pertinent, trustworthy information by systematically acquiring, analyzing, and transferring research findings into clinical, management, and policy arenas. In the United States, researchers, clinicians, professional organizations, and government are looking for a sensible approach to health care with practical evidence-based medicine. All modes of evidence-based practice, either in the form of evidence-based medicine, systematic reviews, meta-analysis, or guidelines, evolve through a methodological, rational accumulation, analysis, and understanding of the evidentiary knowledge that can be applied in clinical settings. Historically, evidence-based medicine is traceable to the 1700s, even though it was not explicitly defined and advanced until the late 1970s and early 1980s. Evidence-based medicine was initially called "critical appraisal" to describe the application of basic rules of evidence as they evolve into application in daily practices. Evidence-based medicine is defined as a conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients. Evidence-based practice is defined based on 4 basic and important contingencies, which include recognition of the patient's problem and construction of a structured clinical question, thorough search of medical literature to retrieve the best available evidence to answer the question, critical appraisal of all available evidence, and integration of the evidence with all aspects and contexts of the clinical circumstances. Systematic reviews provide the application of scientific strategies that limit bias by the systematic assembly, critical appraisal, and synthesis of all relevant studies on a specific topic. While systematic reviews are close to meta-analysis, they are vastly different from narrative reviews and health technology assessments. Clinical practice guidelines are systematically developed statements that aim to help physicians and patients reach the best health care decisions. Appropriately developed guidelines incorporate validity, reliability, reproducibility, clinical applicability and flexibility, clarity, development through a multidisciplinary process, scheduled reviews, and documentation. Thus, evidence-based clinical practice guidelines represent statements developed to improve the quality of care, patient access, treatment outcomes, appropriateness of care, efficiency and effectiveness and achieve cost containment by improving the cost benefit ratio. Part 1 of this series in evidence-based medicine, systematic reviews, and guidelines in interventional pain management provides an introduction and general considerations of these 3 aspects in interventional pain management.

[1]  George Davey Smith,et al.  Meta-analysis: Principles and procedures , 1997, BMJ.

[2]  N. Bogduk,et al.  Management of Acute and Chronic Neck Pain: An Evidence-Based Approach , 2006 .

[3]  Gordon H Guyatt,et al.  Systems for grading the quality of evidence and the strength of recommendations II: Pilot study of a new system , 2005, BMC health services research.

[4]  L. Bero,et al.  Why review articles on the health effects of passive smoking reach different conclusions. , 1998, JAMA.

[5]  A. Oxman,et al.  Improving the use of research evidence in guideline development: 15. Disseminating and implementing guidelines , 2006, Health research policy and systems.

[6]  A Laupacis,et al.  Assessing the quality of randomized trials: reliability of the Jadad scale. , 1999, Controlled clinical trials.

[7]  K. Lohr,et al.  Assessing "best evidence": issues in grading the quality of studies for systematic reviews. , 1999, The Joint Commission journal on quality improvement.

[8]  M. Mayo-Smith,et al.  Are guidelines following guidelines? The methodological quality of clinical practice guidelines in the peer-reviewed medical literature. , 1999, JAMA.

[9]  H S Sacks,et al.  Meta-analysis: an update. , 1996, The Mount Sinai journal of medicine, New York.

[10]  J. Cohen,et al.  Trust us to make a difference: ensuring public confidence in the integrity of clinical research. , 2001, Academic medicine : journal of the Association of American Medical Colleges.

[11]  Lisa A Bero,et al.  Public Health Chronicles , 2005 .

[12]  D. Rennie,et al.  The Cochrane Collaboration. Preparing, maintaining, and disseminating systematic reviews of the effects of health care. , 1995, JAMA.

[13]  M. Clarke,et al.  Identifying relevant studies for systematic reviews , 1995, BMJ.

[14]  I. Olkin,et al.  Meta-analysis of observational studies in epidemiology - A proposal for reporting , 2000 .

[15]  R A Deyo,et al.  Lumbar spinal fusion. A cohort study of complications, reoperations, and resource use in the Medicare population. , 1993, Spine.

[16]  Users' Guides to the Medical Literature (Editorials) , 1993 .

[17]  A. Oxman,et al.  Health Research Policy and Systems BioMed Central Review Improving the use of research evidence in guideline development: 12. Incorporating considerations of equity , 2006 .

[18]  R. Steinbrook Guidance for guidelines. , 2007, The New England journal of medicine.

[19]  Donald D. McGeary,et al.  Cochrane collaboration-based reviews of health-care interventions: are they unequivocal and valid scientifically, or simply nihilistic? , 2002, The spine journal : official journal of the North American Spine Society.

[20]  W. Jonas The evidence house: how to build an inclusive base for complementary medicine. , 2001, The Western journal of medicine.

[21]  Ethan M Balk,et al.  Correlation of quality measures with estimates of treatment effect in meta-analyses of randomized controlled trials. , 2002, JAMA.

[22]  Peter Langhorne,et al.  Integrating Heterogeneous Pieces of Evidence in Systematic Reviews , 1997, Annals of Internal Medicine.

[23]  E. McGlynn,et al.  How good is the quality of health care in the United States? , 1998, The Milbank quarterly.

[24]  C. Deangelis Conflict of interest and the public trust. , 2000, JAMA.

[25]  A. Oxman,et al.  Improving the use of research evidence in guideline development: 9. Grading evidence and recommendations , 2006, Health research policy and systems.

[26]  C D Naylor,et al.  Incorporating variations in the quality of individual randomized trials into meta-analysis. , 1992, Journal of clinical epidemiology.

[27]  S. Dagenais,et al.  What have we learned about the evidence-informed management of chronic low back pain? , 2008, The spine journal : official journal of the North American Spine Society.

[28]  R. Hull,et al.  Antithrombotic therapy for venous thromboembolic disease. , 1986, Chest.

[29]  Kurt P Spindler,et al.  How to Write a Systematic Review , 2007, Clinical orthopaedics and related research.

[30]  Andreas Laupacis,et al.  Differences between systematic reviews and health technology assessments: A trade-off between the ideals of scientific rigor and the realities of policy making , 2004, International Journal of Technology Assessment in Health Care.

[31]  B Burnand,et al.  Development and validation of an international appraisal instrument for assessing the quality of clinical practice guidelines: the AGREE project. , 2003 .

[32]  David L. Sackett,et al.  Evidence based medicine: What it is and what it isn't (reprinted from BMJ, vol 312, pg 71-72, 1996) , 2007 .

[33]  Victor M Montori,et al.  Methodologic Issues in Systematic Reviews and Meta-Analyses , 2003, Clinical orthopaedics and related research.

[34]  L. Manchikanti Health care reform in the United States: radical surgery needed now more than ever. , 2008, Pain physician.

[35]  M. Angell Shattuck Lecture--evaluating the health risks of breast implants: the interplay of medical science, the law, and public opinion. , 1996, The New England journal of medicine.

[36]  S. Hanna,et al.  CHARACTERISTICS OF HIGH-QUALITY GUIDELINES , 2003, International Journal of Technology Assessment in Health Care.

[37]  G H Guyatt,et al.  Users' guides to the medical literature. VI. How to use an overview. Evidence-Based Medicine Working Group. , 1994, JAMA.

[38]  S. Hassenbusch,et al.  Evidence-based practice guidelines for interventional techniques in the management of chronic spinal pain. , 2003, Pain physician.

[39]  A. Oxman,et al.  Improving the use of research evidence in guideline development: 5. Group processes , 2006, Health research policy and systems.

[40]  A R Jadad,et al.  Methodology and reports of systematic reviews and meta-analyses: a comparison of Cochrane reviews with articles published in paper-based journals. , 1998, JAMA.

[41]  R. Haynes Clinical review articles. , 1992, BMJ.

[42]  L. Manchikanti,et al.  Interventional techniques in ambulatory surgical centers: a look at the new payment system. , 2007, Pain physician.

[43]  A. Oxman,et al.  Improving the use of research evidence in guideline development: 7. Deciding what evidence to include , 2006, Health research policy and systems.

[44]  L. Manchikanti Evidence-based interventional pain medicine: is there any evidence. , 2002, Pain physician.

[45]  P. Royle,et al.  Literature searching for clinical and cost-effectiveness studies used in health technology assessment reports carried out for the National Institute for Clinical Excellence appraisal system. , 2003, Health technology assessment.

[46]  Gordon Guyatt,et al.  An emerging consensus on grading recommendations? , 2006, ACP journal club.

[47]  Deborah J Cook,et al.  Trials and tribulations of systematic reviews and meta-analyses. , 2007, Hematology. American Society of Hematology. Education Program.

[48]  G. Smith,et al.  Meta-analysis: Potentials and promise , 1997, BMJ.

[49]  I. Chalmers The Cochrane Collaboration: Preparing, Maintaining, and Disseminating Systematic Reviews of the Effects of Health Care , 1993, Annals of the New York Academy of Sciences.

[50]  P. Friedman The impact of conflict of interest on trust in science , 2002, Science and engineering ethics.

[51]  C. Bombardier,et al.  A Critical Review of Reviews on the Treatment of Chronic Low Back Pain , 2001, Spine.

[52]  L. Manchikanti,et al.  Physician payment 2008 for interventionalists: current state of health care policy. , 2007, Pain physician.

[53]  R Peto,et al.  Why do we need systematic overviews of randomized trials? , 1987, Statistics in medicine.

[54]  Andrew D Oxman,et al.  Health Research Policy and Systems BioMed Central Review Improving the use of research evidence in guideline development: 13. Applicability, transferability and adaptation , 2006 .

[55]  F Davidoff,et al.  Systematic Reviews: Critical Links in the Great Chain of Evidence , 1997, Annals of Internal Medicine.

[56]  D. Cook,et al.  Assessing the quality of reports of randomised trials: implications for the conduct of meta-analyses. , 1999, Health technology assessment.

[57]  I. Coulter Evidence Summaries and Synthesis: Necessary but Insufficient Approach for Determining Clinical Practice of Integrated Medicine? , 2006, Integrative cancer therapies.

[58]  A. Oxman,et al.  Improving the use of research evidence in guideline development: 10. Integrating values and consumer involvement , 2006, Health research policy and systems.

[59]  D. Moher,et al.  Guides for reading and interpreting systematic reviews: I. Getting started. , 1998, Archives of pediatrics & adolescent medicine.

[60]  A R Jadad,et al.  Assessing the Quality of Randomized Controlled Trials: Current Issues and Future Directions , 1996, International Journal of Technology Assessment in Health Care.

[61]  R A Deyo,et al.  Morbidity and mortality in association with operations on the lumbar spine. The influence of age, diagnosis, and procedure. , 1992, The Journal of bone and joint surgery. American volume.

[62]  W. Jonas Building an Evidence House: Challenges and Solutions to Research in Complementary and Alternative Medicine , 2005, Complementary Medicine Research.

[63]  B J McNeil,et al.  Shattuck Lecture--Hidden barriers to improvement in the quality of care. , 2001, The New England journal of medicine.

[64]  E. Boyd,et al.  Improving the use of research evidence in guideline development: 4. Managing conflicts of interests , 2006, Health research policy and systems.

[65]  J. Harris,et al.  Development, use, and evaluation of clinical practice guidelines. , 1997, Journal of occupational and environmental medicine.

[66]  Giancarlo Agnelli,et al.  Antithrombotic therapy for venous thromboembolic disease: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy. , 2004, Chest.

[67]  A. Wall,et al.  Book ReviewTo Err is Human: building a safer health system Kohn L T Corrigan J M Donaldson M S Washington DC USA: Institute of Medicine/National Academy Press ISBN 0 309 06837 1 $34.95 , 2000 .

[68]  J. Giordano Pain research: can paradigmatic expansion bridge the demands of medicine, scientific philosophy and ethics? , 2004, Pain Physician.

[69]  D. Altman Confidence intervals in research evaluation , 1992, ACP Journal Club.

[70]  P. Shekelle,et al.  Is the methodological quality of guidelines declining in the US? Comparison of the quality of US Agency for Health Care Policy and Research (AHCPR) guidelines with those published subsequently , 2003, Quality & safety in health care.

[71]  E. Kalso,et al.  Radiofrequency Denervation for Neck and Back Pain: A Systematic Review Within the Framework of the Cochrane Collaboration Back Review Group , 2003, Spine.

[72]  D. Cook,et al.  Methodologic guidelines for systematic reviews of randomized control trials in health care from the Potsdam Consultation on Meta-Analysis. , 1995, Journal of clinical epidemiology.

[73]  D. Moher,et al.  Guides for reading and interpreting systematic reviews: III. How did the authors synthesize the data and make their conclusions? , 1998, Archives of pediatrics & adolescent medicine.

[74]  I Olkin,et al.  Heterogeneity and statistical significance in meta-analysis: an empirical study of 125 meta-analyses. , 2000, Statistics in medicine.

[75]  L. Manchikanti,et al.  Methods for evidence synthesis in interventional pain management. , 2003, Pain physician.

[76]  D. Parr,et al.  How to restore public trust in science , 1999, Nature.

[77]  L. Manchikanti,et al.  Interventional techniques in the management of chronic pain: Part 2.0. , 2001, Pain physician.

[78]  C. Gross,et al.  Scope and impact of financial conflicts of interest in biomedical research: a systematic review. , 2003, JAMA.

[79]  B. Djulbegovic,et al.  Pharmaceutical industry sponsorship and research outcome and quality: systematic review , 2003, BMJ : British Medical Journal.

[80]  J. Drazen,et al.  To protect those who serve. , 2000, The New England journal of medicine.

[81]  Gordon Guyatt,et al.  Evaluating the teaching of evidence-based medicine. , 2002, JAMA.

[82]  Gordon H. Guyatt,et al.  Users' Guides to the Medical Literature: VIII. How to Use Clinical Practice Guidelines A. Are the Recommendations Valid? , 1995 .

[83]  J. Cates,et al.  An independent AGREE evaluation of the Occupational Medicine Practice Guidelines. , 2006, The spine journal : official journal of the North American Spine Society.

[84]  K. Hopayian,et al.  The need for caution in interpreting high quality systematic reviews , 2001, BMJ : British Medical Journal.

[85]  J. Giordano Moral agency in pain medicine: philosophy, practice and virtue. , 2006, Pain physician.

[86]  H. Ursin,et al.  Chapter 4 European guidelines for the management of chronic nonspecific low back pain , 2006, European Spine Journal.

[87]  A R Jadad,et al.  Guides for reading and interpreting systematic reviews: II. How did the authors find the studies and assess their quality? , 1998, Archives of pediatrics & adolescent medicine.

[88]  T C Chalmers,et al.  Getting to grips with Archie Cochrane's agenda. , 1992, BMJ.

[89]  C. Mulrow The medical review article: state of the science. , 1987, Annals of internal medicine.

[90]  S. Greenland Quality Scores Are Useless and Potentially Misleading: Reply to “Re: A Critical Look at Some Popular Analytic Methods” , 1994 .

[91]  Gordon H Guyatt,et al.  Users' guide to detecting misleading claims in clinical research reports , 2004, BMJ : British Medical Journal.

[92]  J. Pignon,et al.  Review article: critical review of meta‐analyses of randomized clinical trials in hepatogastroenterology , 1997, Alimentary pharmacology & therapeutics.

[93]  D. Egilman,et al.  Evaluating the health risks of breast implants. , 1996, The New England journal of medicine.

[94]  G. Guyatt,et al.  Grading strength of recommendations and quality of evidence in clinical guidelines: report from an american college of chest physicians task force. , 2006, Chest.

[95]  G. Guyatt,et al.  Systems for grading the quality of evidence and the strength of recommendations I: Critical appraisal of existing approaches The GRADE Working Group , 2004, BMC health services research.

[96]  G H Guyatt,et al.  Transferring evidence from research into practice: 1. The role of clinical care research evidence in clinical decisions , 1996, Evidence Based Medicine.

[97]  R. Grol,et al.  Guideline development in Europe. An international comparison , 2000 .

[98]  L. Manchikanti,et al.  The role of guidelines in interventional pain medicine: let us separate apples and oranges. , 2001, Pain physician.

[99]  D M Eddy,et al.  The quality of medical evidence: implications for quality of care. , 1988, Health affairs.

[100]  K. Lohr Rating the strength of scientific evidence: relevance for quality improvement programs. , 2004, International journal for quality in health care : journal of the International Society for Quality in Health Care.

[101]  Andrew D Oxman,et al.  Improving the use of research evidence in guideline development: 1. Guidelines for guidelines , 2006, Health research policy and systems.

[102]  P. Budetti Market justice and US health care. , 2008, JAMA.

[103]  K N Lohr,et al.  Health policy issues and applications for evidence-based medicine and clinical practice guidelines. , 1998, Health policy.

[104]  P Middleton,et al.  Quality of Cochrane reviews: assessment of sample from 1998 , 2001, BMJ : British Medical Journal.

[105]  Karen Golden-Biddle,et al.  Towards systematic reviews that inform health care management and policy-making , 2005, Journal of health services research & policy.

[106]  M. Mäkelä,et al.  GUIDELINE DEVELOPMENT IN EUROPE , 2000, International Journal of Technology Assessment in Health Care.

[107]  David Moher,et al.  The Medical Review Article Revisited: Has the Science Improved? , 1999, Annals of Internal Medicine.

[108]  G. Piaggio,et al.  Factors affecting the comparability of meta-analyses and largest trials results in perinatology. , 1997, Journal of clinical epidemiology.

[109]  G. Omenn,et al.  The messenger under attack -- intimidation of researchers by special-interest groups. , 1997, The New England journal of medicine.

[110]  L. Bero,et al.  Scientific quality of original research articles on environmental tobacco smoke , 1997, Tobacco Control.

[111]  Claire Glenton,et al.  Summaries of findings, descriptions of interventions, and information about adverse effects would make reviews more informative. , 2006, Journal of clinical epidemiology.

[112]  E. Hemminki Quality of reports of clinical trials submitted by the drug industry to the Finnish and Swedish control authorities , 1981, European Journal of Clinical Pharmacology.

[113]  P. Tugwell,et al.  A Comparison of the Quality of Cochrane Reviews and Systematic Reviews Published in Paper-Based Journals , 2002, Evaluation & the health professions.

[114]  L. Manchikanti,et al.  Evidence synthesis and development of guidelines in interventional pain management. , 2005, Pain physician.

[115]  D. Rennie,et al.  Prevalence of honorary and ghost authorship in Cochrane reviews. , 2002, JAMA.

[116]  G. Feder,et al.  Development and validation of an international appraisal instrument for assessing the quality of clinical practice guidelines: the AGREE project , 2003, Quality & safety in health care.

[117]  N McKoy,et al.  Systems to rate the strength of scientific evidence. , 2002, Evidence report/technology assessment.

[118]  T C Chalmers,et al.  A method for assessing the quality of a randomized control trial. , 1981, Controlled clinical trials.

[119]  J M Eisenberg What Does Evidence Mean? Can the Law and Medicine Be Reconciled? , 2001, Journal of health politics, policy and law.

[120]  T. Edejer Improving the use of research evidence in guideline development: 11. Incorporating considerations of cost-effectiveness, affordability and resource implications , 2006, Health Research Policy and Systems.

[121]  D. Petitti,et al.  Approaches to heterogeneity in meta‐analysis , 2001, Statistics in medicine.

[122]  F. Mosteller,et al.  A comparison of results of meta-analyses of randomized control trials and recommendations of clinical experts. Treatments for myocardial infarction. , 1992, JAMA.

[123]  M. Cho,et al.  The Quality of Drug Studies Published in Symposium Proceedings , 1996, Annals of Internal Medicine.

[124]  Andrew D Oxman,et al.  Letters, numbers, symbols and words: how to communicate grades of evidence and recommendations. , 2003, CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne.

[125]  A. Frank,et al.  American College of Occupational and Environmental Medicine (ACOEM): A Professional Association in Service to Industry , 2007, International journal of occupational and environmental health.

[126]  A. Oxman,et al.  Improving the use of research evidence in guideline development: 3. Group composition and consultation process , 2006, Health research policy and systems.

[127]  A. Oxman,et al.  Improving the use of research evidence in guideline development: 16. Evaluation , 2006, Health research policy and systems.

[128]  Howard S. Smith,et al.  Interventional techniques: evidence-based practice guidelines in the management of chronic spinal pain. , 2007, Pain physician.

[129]  K. Dickersin,et al.  Systematic Reviews: Identifying relevant studies for systematic reviews , 1994 .

[130]  L. Manchikanti,et al.  Evidence-based interventional pain management: principles, problems, potential and applications. , 2007, Pain physician.

[131]  Freeman A Treatise on the Principles and Practice of Medicine; Designed for the Use of Practitioners and Students of Medicine , 1867, Atlanta Medical and Surgical Journal.

[132]  Andrew D Oxman,et al.  Improving the use of research evidence in guideline development , 2007 .

[133]  Douglas G Altman,et al.  Systematic reviews in health care: Assessing the quality of controlled clinical trials. , 2001, BMJ.

[134]  K. Dickersin The existence of publication bias and risk factors for its occurrence. , 1990, JAMA.

[135]  A D Oxman,et al.  Systematic Reviews: Checklists for review articles , 1994, BMJ.

[136]  S. Dagenais,et al.  A supermarket approach to the evidence-informed management of chronic low back pain. , 2008, The spine journal : official journal of the North American Spine Society.

[137]  L. Bouter,et al.  A Critical Appraisal of Review Articles on the Effectiveness of Conservative Treatment for Neck Pain , 2001, Spine.

[138]  A. Jadad,et al.  The importance of quality of primary studies in producing unbiased systematic reviews. , 1996, Archives of internal medicine.

[139]  Jonathan A C Sterne,et al.  Systematic reviews in health care: Investigating and dealing with publication and other biases in meta-analysis. , 2001, BMJ.

[140]  A. Gittelsohn,et al.  Small Area Variations in Health Care Delivery , 1973, Science.

[141]  A R Jadad,et al.  Searching the literature. Be systematic in your searching. , 1993, BMJ.

[142]  A R Jadad,et al.  Systematic reviews and meta-analyses on treatment of asthma: critical evaluation , 2000, BMJ : British Medical Journal.

[143]  G. Guyatt,et al.  Practice guidelines , 1996, Journal of General Internal Medicine.

[144]  Mark V. Williams,et al.  Users’ Guides to the Medical Literature: A Manual for Evidence-Based Clinical Practice , 2002, ACP Journal Club.

[145]  Andrew D Oxman,et al.  Improving the use of research evidence in guideline development: 2. Priority setting , 2006, Health research policy and systems.

[146]  F. Song,et al.  QUALITY-ASSESSED REVIEWS OF HEALTH CARE INTERVENTIONS AND THE DATABASE OF ABSTRACTS OF REVIEWS OF EFFECTIVENESS (DARE) , 1999, International Journal of Technology Assessment in Health Care.

[147]  W. McIlroy,et al.  Should unpublished data be included in meta-analyses? Current convictions and controversies. , 1993, JAMA.

[148]  Evidence-based medicine in managed care: a survey of current and emerging strategies. , 2004, MedGenMed : Medscape general medicine.

[149]  G. Guyatt,et al.  Grading quality of evidence and strength of recommendations , 2004, BMJ : British Medical Journal.

[150]  Frederick Mosteller,et al.  Guidelines for Meta-analyses Evaluating Diagnostic Tests , 1994, Annals of Internal Medicine.

[151]  J. Haselkorn,et al.  Patient outcomes after lumbar spinal fusions. , 1992, JAMA.

[152]  E. Benzel,et al.  A fair and balanced view of spine fusion surgery. , 2004, The spine journal : official journal of the North American Spine Society.

[153]  A. Oxman,et al.  Improving the use of research evidence in guideline development: 14. Reporting guidelines , 2006, Health research policy and systems.

[154]  A. Oxman,et al.  Improving the use of research evidence in guideline development: 8. Synthesis and presentation of evidence , 2006, Health research policy and systems.

[155]  R. Napodano Values in Medical Practice: A Statement of Philosophy for Physicians and a Model for Teaching a Healing Science , 1986 .

[156]  D. Cook,et al.  Systematic Reviews: Synthesis of Best Evidence for Clinical Decisions , 1997, Annals of Internal Medicine.

[157]  P. Gøtzsche Methodology and overt and hidden bias in reports of 196 double-blind trials of nonsteroidal antiinflammatory drugs in rheumatoid arthritis. , 1989, Controlled clinical trials.