Systematic and Nonsystematic Reviews: Choosing an Approach

  • David A. CookEmail author


Systematic reviews and purposive (nonsystematic) reviews serve valuable and complementary roles in synthesizing the results of original research studies. Systematic reviews use rigorous methods of article selection and data extraction to shed focused, deep light on a relatively narrow body of research, yet of necessity may exclude potentially insightful works that fall outside the predefined scope. Purposive reviews offer flexibility to address more far-reaching questions and pursue novel insights, yet offer little assurance of a balanced perspective on the issue. This chapter reviews the strengths and weaknesses of each approach, and suggests specific questions to help researchers select among these approaches. Different approaches to quantitative and narrative research synthesis, including meta-analysis, are also described.


Literature review Systematic review Nonsystematic review Purposive review Meta-analysis Research synthesis 


  1. 1.
    Grant MJ, Booth A. A typology of reviews: an analysis of 14 review types and associated methodologies. Health Inf Libr J. 2009;26:91–108.CrossRefGoogle Scholar
  2. 2.
    Pawson R, Greenhalgh T, Harvey G, Walshe K. Realist review – a new method of systematic review designed for complex policy interventions. J Health Serv Res Policy. 2005;10(Suppl 1):21–34.CrossRefGoogle Scholar
  3. 3.
    Arksey H, O’Malley L. Scoping studies: towards a methodological framework. Int J Soc Res Methodol. 2005;8:19–32.CrossRefGoogle Scholar
  4. 4.
    Levac D, Colquhoun H, O’Brien KK. Scoping studies: advancing the methodology. Implement Sci. 2010;5:69.CrossRefGoogle Scholar
  5. 5.
    Cook DA. Narrowing the focus and broadening horizons: complementary roles for nonsystematic and systematic reviews. Adv Health Sci Educ Theory Pract. 2008;13:391–5.CrossRefGoogle Scholar
  6. 6.
    Cook DA. Randomized controlled trials and meta-analysis in medical education: what role do they play? Med Teach. 2012;34:468–73.CrossRefGoogle Scholar
  7. 7.
    Eva KW. On the limits of systematicity. Med Educ. 2008;42:852–3.CrossRefGoogle Scholar
  8. 8.
    Cook DA. Tips for a great review article: crossing methodological boundaries. Med Educ. 2016;50:384–7.CrossRefGoogle Scholar
  9. 9.
    Cook DA, Bordage G, Schmidt HG. Description, justification, and clarification: a framework for classifying the purposes of research in medical education. Med Educ. 2008;42:128–33.CrossRefGoogle Scholar
  10. 10.
    Cooper H, Hedges LV, Valentine JC. The handbook of research synthesis. 2nd ed. New York: Russell Sage Foundation; 2009.Google Scholar
  11. 11.
    Higgins JPT, Green S. Cochrane handbook for systematic reviews of interventions. Chichester: Wiley-Blackwell; 2008.CrossRefGoogle Scholar
  12. 12.
    Cook DA, West CP. Conducting systematic reviews in medical education: a stepwise approach. Med Educ. 2012;46:943–52.CrossRefGoogle Scholar
  13. 13.
    Cook DJ, Mulrow CD, Haynes RB. Systematic reviews: synthesis of best evidence for clinical decisions. Ann Intern Med. 1997;126:376–80.CrossRefGoogle Scholar
  14. 14.
    Higgins JPT, Green S. Cochrane handbook for systematic reviews of interventions 5.1.0 [updated March 2011]. Available at: Accessed 31 May 2018.
  15. 15.
    Campbell Collaboration. Campbell Collaboration Resource Center. Available at: Accessed 31 May 2018.
  16. 16.
    Moher D, Liberati A, Tetzlaff J, Altman DG. Preferred reporting items for systematic reviews and meta-analyses: The PRISMA statement. Ann Intern Med. 2009;151:264–9.CrossRefGoogle Scholar
  17. 17.
    Wong G, Greenhalgh T, Westhorp G, Buckingham J, Pawson R. RAMESES publication standards: realist syntheses. BMC Med. 2013;11:21.CrossRefGoogle Scholar
  18. 18.
    Montori VM, Swiontkowski MF, Cook DJ. Methodologic issues in systematic reviews and meta-analyses. Clin Orthop Relat Res. 2003;413:43–54.CrossRefGoogle Scholar

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© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Mayo Clinic Multidisciplinary Simulation Center, Office of Applied Scholarship and Education Science, and Division of General Internal MedicineMayo Clinic College of Medicine and ScienceRochesterUSA

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