How pragmatic or explanatory is the randomized, controlled trial? The application and enhancement of the PRECIS tool to the evaluation of a smoking cessation trial
Numerous explanatory randomized trials support the efficacy of chronic disease interventions, including smoking cessation treatments. However, there is often inadequate adoption of these interventions for various reasons, one being the limitation of generalizability of the explanatory studies in real-world settings. Randomized controlled trials can be rated as more explanatory versus pragmatic along 10 dimensions. Pragmatic randomized clinical trials generate more realistic estimates of effectiveness with greater relevance to clinical practice and for health resource allocation decisions. However, there is no clear method to scale each dimension during the trial design phase to ensure that the design matches the intended purpose of the study.
We designed a pragmatic, randomized, controlled study to maximize external validity by addressing several barriers to smoking cessation therapy in ambulatory care. We analyzed our design and methods using the recently published ‘Pragmatic–Explanatory Continuum Indicatory Summary (PRECIS)’ tool, a qualitative method to assess trial design across 10 domains. We added a 20-point numerical rating scale and a modified Delphi process to improve consensus in rating these domains.
After two rounds of review, there was consensus on all 10 domains of study design. No single domain was scored as either fully pragmatic or fully explanatory; but overall, the study scored high on pragmatism.
This addition to the PRECIS tool may assist other trial designers working with interdisciplinary co-investigators to rate their study design while building consensus.
- Schwartz D, Lellouch J: Explanatory and pragmatic attitudes in therapeutical trials. J Chronic Dis 1967, 20:637–648. CrossRef
- Guyatt GH, Sackett DL, Cook DJ: Users’ guides to the medical literature. II. How to use an article about therapy or prevention. B. What were the results and will they help me in caring for my patients? Evidence-Based Medicine Working Group. JAMA 1994, 271:59–63. CrossRef
- 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, 290:1624–1632. CrossRef
- March JS, Silva SG, Compton S, Shapiro M, Califf R, Krishnan R: The case for practical clinical trials in psychiatry. Am J Psychiatry 2005, 162:836–846. CrossRef
- Glasgow RE, Emmons KM: How can we increase translation of research into practice? Types of evidence needed. Annu Rev Public Health 2007, 28:413–433. CrossRef
- Liberati A: The relationship between clinical trials and clinical practice: the risks of underestimating its complexity. Stat Med 1994, 13:1485–1491. CrossRef
- Glasgow RE, Magid DJ, Beck A, Ritzwoller D, Estabrooks PA: Practical clinical trials for translating research to practice: design and measurement recommendations. Med Care 2005, 43:551–557. CrossRef
- Gartlehner G, Hansen RA, Nissman D, Lohr KN, Carey TS: A simple and valid tool distinguished efficacy from effectiveness studies. J Clin Epidemiol 2006, 59:1040–1048. CrossRef
- Jepsen P, Johnsen SP, Gillman MW, Sørensen HT: Interpretation of observational studies. Heart 2004, 90:956–960. CrossRef
- Hannan EL: Randomized clinical trials and observational studies: guidelines for assessing respective strengths and limitations. JACC Cardiovasc Interv 2008, 1:211–217. CrossRef
- Mullins CD, Whicher D, Reese ES, Tunis S: Generating evidence for comparative effectiveness research using more pragmatic randomized controlled trials. Pharmacoeconomics 2010, 28:969–976. CrossRef
- 2008 PHS Guideline Update Panel, Liaisons, and Staff: Treating tobacco use and dependence: 2008 update U.S. Public Health Service Clinical Practice Guideline executive summary. Respir Care 2008, 53:1217–1222.
- Cahill K, Stead LF, Lancaster T: Nicotine receptor partial agonists for smoking cessation. Cochrane Database Syst Rev 2010, 12:CD006103.
- Hughes JR, Stead LF, Lancaster T: Antidepressants for smoking cessation. Cochrane Database Syst Rev 2007, 1:CD000031.
- Stead LF, Perera R, Bullen C, Mant D, Lancaster T: Nicotine replacement therapy for smoking cessation. Cochrane Database Syst Rev 2008, 1:CD000146.
- Thorpe KE, Zwarenstein M, Oxman AD, Treweek S, Furberg CD, Altman DG, Tunis S, Bergel E, Harvey I, Magid DJ, Chalkidou K: A pragmatic-explanatory continuum indicator summary (PRECIS): a tool to help trial designers. J Clin Epidemiol 2009, 62:464–475. CrossRef
- Riddle DL, Johnson RE, Jensen MP, Keefe FJ, Kroenke K, Bair MJ, Ang DC: The Pragmatic-Explanatory Continuum Indicator Summary (PRECIS) instrument was useful for refining a randomized trial design: experiences from an investigative team. J Clin Epidemiol 2010, 63:1271–1275. CrossRef
- Bratton DJ, Nunn AJ: Alternative approaches to tuberculosis treatment evaluation: the role of pragmatic trials. Int J Tuberc Lung Dis 2011, 15:440–446. CrossRef
- Tosh G, Soares-Weiser K, Adams CE: Pragmatic vs explanatory trials: the pragmascope tool to help measure differences in protocols of mental health randomized controlled trials. Dialogues Clin Neurosci 2011, 13:209–215.
- Glasgow RE, Gaglio B, Bennett G, Jerome GJ, Yeh HC, Sarwer DB, Appel L, Colditz G, Wadden TA, Wells B: Applying the PRECIS criteria to describe three effectiveness trials of weight loss in obese patients with comorbid conditions. Health Serv Res 2011. [Epub ahead of print] Nov 2
- Koppenaal T, Linmans J, Knottnerus JA, Spigt M: Pragmatic vs. explanatory: an adaptation of the PRECIS tool helps to judge the applicability of systematic reviews for daily practice. J Clin Epidemiol 2011, 64:1095–1101. CrossRef
- Spigt MG, Kotz D: Comment on: ‘a simple and valid tool distinguished efficacy from effectiveness studies’. J Clin Epidemiol 2007, 60:753–755. CrossRef
- Mullen PM: Delphi: myths and reality. J Health Organ Manag 2003, 17:37–52. CrossRef
- The pre-publication history for this paper can be accessed here:http://www.biomedcentral.com/1471-2288/12/101/prepub
- How pragmatic or explanatory is the randomized, controlled trial? The application and enhancement of the PRECIS tool to the evaluation of a smoking cessation trial
- Open Access
- Available under Open Access This content is freely available online to anyone, anywhere at any time.
BMC Medical Research Methodology
- Online Date
- July 2012
- Online ISSN
- BioMed Central
- Additional Links
- Clinical trial
- Smoking cessation
- Nicotine replacement therapy
- Author Affiliations
- 1. Addictions Program, Centre for Addiction and Mental Health, 100 Stokes St., 33 Russell Street, Toronto, ON, M6J 1H4, Canada
- 2. Departments of Family and Community Medicine and Psychiatry and the Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada
- 3. Ontario Tobacco Research Unit, Toronto, ON, Canada
- 4. Department of Family Medicine, Dalhousie University, Halifax, NS, Canada
- 5. Cardiac Rehabilitation and Secondary Prevention Program, Toronto Rehabilitation Institute, Toronto, ON, Canada
- 6. Department of Medicine, University of Toronto, Toronto, ON, Canada
- 7. Health Economics & Outcomes Research, Pfizer Canada Inc, Kirkland, Québec, Canada
- 8. Therapeutic Areas, Cardiovascular and Respiratory, Medical Division, Pfizer Canada Inc, Kirkland, Québec, Canada