What kind of randomized trials do patients and clinicians need?
Authors: Merrick Zwarenstein
Journal: Annals of Internal Medicine (2009)

ACP Journal Club19 May 2009What kind of randomized trials do patients and clinicians need?Merrick Zwarenstein, MBBCh, MSc, Shaun Treweek, PhDMerrick Zwarenstein, MBBCh, MScCentre for Health Services Sciences, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada (M.Z.), Shaun Treweek, PhDUniversity of Dundee, Dundee, Scotland, UK (S.T.)Author, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-150-10-200905190-02002 SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail In 1967, Daniel Schwartz and Joseph Lellouch (1) argued that there are 2 kinds of randomized controlled trials (RCTs), which embody radically different attitudes to evaluation of treatment. They named these trials "pragmatic" and "explanatory" and stated that these 2 attitudes require different approaches to the design of a randomized trial. The pragmatic attitude seeks to directly inform real-world decisions among alternative treatments, and Schwartz and Lellouch (1) show that this purpose is satisfied in trials that test feasible interventions on typical patients in common settings, with usual care as the comparator, to widen real-world applicability. In contrast, the explanatory ...References1 Schwartz D, Lellouch J. Explanatory and pragmatic attitudes in therapeutical trials. J Chronic Dis. 1967;20:637-48. [PMID: 4860352] Google Scholar2 Rothwell PM. External validity of randomised controlled trials: "to whom do the results of this trial apply?" Lancet. 2005;365:82-93. [PMID: 15639683] Google Scholar3 North American Symptomatic Carotid Endarterectomy Trial Collaborators. Beneficial effect of carotid endarterectomy in symptomatic patients with high-grade carotid stenosis. N Engl J Med. 1991;325:445-53. [PMID: 1852179] Google Scholar4 Wing LM, Reid CM, Ryan P, et al, for the Second Australian National Blood Pressure Study Group. A comparison of outcomes with angiotensin-converting-enzyme inhibitors and diuretics for hypertension in the elderly. N Engl J Med. 2003;348:583-92. [PMID: 12584366] Google Scholar5 Vallvé C. [A critical review of the pragmatic clinical trial]. Med Clin (Barc). 2003;121:384-8. [PMID: 14565915] Google Scholar6 Van Spall HG, Toren A, Kiss A, Fowler RA. Eligibility criteria of randomized controlled trials published in high-impact general medical journals: a systematic sampling review. JAMA. 2007;297:1233-40. [PMID: 17374817] Google Scholar7 US Food and Drug Administration. Guidance for institutional review boards and clinical investigators. 1998 update. www.fda.gov/oc/ohrt/irbs/drugsbiologics.html#study (accessed 14 Mar 09). Google Scholar8 Tunis SR, Stryer DB, Clancy CM. Practical clinical trials: increasing the value of clinical research for decision making in clinical and health policy. JAMA. 2003;290:1624-32. [PMID: 14506122] Google Scholar9 Congressional Budget Office. Research on the comparative effectiveness of medical treatments: issues and options for an expanded federal role. Report Pub. No. 2975. Washington: Congressional Budget Office, Dec 2007. www.cbo.gov/ftpdocs/88xx/doc8891/12-18-ComparativeEffectiveness.pdf (accessed 14 Apr 2009). Google Scholar10 Thorpe KE, Zwarenstein M, Oxman AD, et al. A pragmatic–explanatory continuum indicator summary (PRECIS): a tool to help trial designers. J Clin Epidemiol. 2009;62:464-75. [PMID: 19348971] Google Scholar11 Zwarenstein M, Treweek S, Gagnier JJ, et al, for the CONSORT group and Pragmatic Trials in Healthcare (Practihc) group. Improving the reporting of pragmatic trials: an extension of the CONSORT statement. BMJ. 2008;337:a2390. [PMID: 19001484] Google Scholar Author, Article, and Disclosure InformationAffiliations: Centre for Health Services Sciences, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada (M.Z.)University of Dundee, Dundee, Scotland, UK (S.T.)This article was published at Annals.org on 5 May 2009. PreviousarticleNextarticle Advertisement FiguresReferencesRelatedDetails Metrics Cited ByVirtual Reality exposure therapy for public speaking anxiety in routine care: a single-subject effectiveness trialLoopholes in the Research Ethics System? Informed Consent Waivers in Cluster Randomized Trials with Individual‐Level InterventionA careful biomedicine? Generalization and abstraction in RCTsPerspective: Randomized Controlled Trials Are Not a Panacea for Diet-Related ResearchCan Database Studies Be Used to Make the Tough Research Decisions?A Transdiagnostic Internet-Based Maintenance Treatment Enhances the Stability of Outcome after Inpatient Cognitive Behavioral Therapy: A Randomized Controlled Trial 19 May 2009Volume 150, Issue 10Page: JC5-2KeywordsBlood pressureClinical trial reportingClinical trialsDecision makingHealth careStrokeSystolic pressure ePublished: 19 May 2009 Issue Published: 19 May 2009 CopyrightCopyright © 2009 by American College of Physicians. All Rights Reserved.PDF DownloadLoading ...