Journal of Clinical Epidemiology
Volume 63, Issue 3 , Pages 246-256 , March 2010

Trial sequential analyses of meta-analyses of complications in laparoscopic vs. small-incision cholecystectomy: more randomized patients are needed

  • Frederik Keus

      Affiliations

    • The Cochrane Hepato-Biliary Group, Copenhagen Trial Unit, Center for Clinical Intervention Research, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
    • The Department of Surgery, Diakonessenhuis, Utrecht, the Netherlands
    • Corresponding Author InformationCorresponding author. Department of Surgery, Diakonessenhuis, Bosboomstraat 1, 3582 KE Utrecht, The Netherlands. Tel.: +31-30-2-566-566x6054, +31-30-2-566-225; fax: +31-30-2569759.
    • ,
  • Jørn Wetterslev

      Affiliations

    • The Cochrane Hepato-Biliary Group, Copenhagen Trial Unit, Center for Clinical Intervention Research, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
    • ,
  • Christian Gluud

      Affiliations

    • The Cochrane Hepato-Biliary Group, Copenhagen Trial Unit, Center for Clinical Intervention Research, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
    • ,
  • Hein G. Gooszen

      Affiliations

    • Department of Surgery, University Medical Center, Utrecht, the Netherlands
    • ,
  • Cornelis J.H.M. van Laarhoven

      Affiliations

    • The Cochrane Hepato-Biliary Group, Copenhagen Trial Unit, Center for Clinical Intervention Research, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
    • Department of Surgery, University Medical Center St. Radboud, Nijmegen, the Netherlands

,Accepted 31 August 2009.

References 

  1. Sutton AJ, Higgins JP. Recent developments in meta-analysis. Stat Med. 2007;27:625–650
  2. Straus SE, Richardson WS, Glasziou P, Haynes RB. Evidence-based medicine. How to practice and teach EBM. 3rd ed. London, UK: Churchill Livingstone; 2005;
  3. Lau J, Schmid CH, Chalmers TC. Cumulative meta-analysis of clinical trials builds evidence for exemplary medical care. J Clin Epidemiol. 1995;48:45–57
  4. Wetterslev J, Thorlund K, Brok J, Gluud C. Trial sequential analysis may establish when firm evidence is reached in cumulative meta-analysis. J Clin Epidemiol. 2008;61:64–75
  5. Schulz KF, Chalmers I, Hayes RJ, Altman DG. Empirical evidence of bias. Dimensions of methodological quality associated with estimates of treatment effects in controlled trials. JAMA. 1995;273:408–412
  6. Moher D, Pham B, Jones A, Cook DJ, Jadad AR, Moher M, et al. Does quality of reports of randomised trials affect estimates of intervention efficacy reported in meta-analyses?. Lancet. 1998;352:609–613
  7. Kjaergard LL, Villumsen J, Gluud C. Reported methodologic quality and discrepancies between large and small randomized trials in meta-analyses. Ann Intern Med. 2001;135:982–989
  8. Wood L, Egger M, Gluud LL, Schulz KF, Jüni P, Altman DG, et al. Empirical evidence of bias in treatment effect estimates in controlled trials with different interventions and outcomes: meta-epidemiological study. BMJ. 2008;336:601–605
  9. Guyatt GH, Oxman AD, Kunz R, Vist GE, Falck-Ytter Y, Schünemann HJ. What is “quality of evidence” and why is it important to clinicians?. BMJ. 2008;336:995–998
  10. Friedman LM, Furberg CD, Demets DL. Fundamentals of clinical trials. New York, NY: Springer Verlag; 1998;
  11. Brok J, Thorlund K, Gluud C, Wetterslev J. Trial sequential analysis reveals insufficient information size and potentially false positive results in many meta-analyses. J Clin Epidemiol. 2008;61:763–769
  12. Brok J, Thorlund K, Wetterslev J, Gluud C. Apparently conclusive meta-analyses may be inconclusive—trial sequential analysis adjustment of random error risk due to repetitive testing of accumulating data in apparently conclusive neonatal meta-analyses. Int J Epidemiol. 2009;38:287–298
  13. Thorlund K, Devereaux PJ, Wetterslev J, Guyatt G, Ioannidis JP, Thabane L, et al. Can trial sequential monitoring boundaries reduce spurious inferences from meta-analyses?. Int J Epidemiol. 2009;38:276–286
  14. Bangalore S, Wetterslev J, Pranesh S, Sawhney S, Gluud C, Messerli FH. Peri-operative beta-blockers in patients undergoing non-cardiac surgery. A meta-analysis and trial sequential analysis of 12,306 patients from randomised trials. Lancet. 2008;372:1962–1976
  15. Nuesch E, Juni P. Commentary: which meta-analyses are conclusive?. Int J Epidemiol. 2009;38:298–303
  16. Keus F, de Jong JAF, Gooszen HG, van Laarhoven CJHM. Laparoscopic versus small-incision cholecystectomy for patients with symptomatic cholecystolithiasis. Cochrane Database Syst Rev. 2006;4:CD006229
  17. Keus F, Gooszen HG, van Laarhoven CJHM. Systematic review: open, small-incision or laparoscopic cholecystectomy for symptomatic cholecystolithiasis. Aliment Pharmacol Ther. 2009;29:359–378
  18. Atkins D, Eccles M, Flottorp S, Guyatt GH, Henry D, Hill S, et al. Systems for grading the quality of evidence and the strength of recommendations I: critical appraisal of existing approaches. The GRADE Working Group. BMC Health Serv Res. 2004;4:38
  19. Atkins D, Briss PA, Eccles M, Flottorp S, Guyatt GH, Harbour RT, et al. Systems for grading the quality of evidence and the strength of recommendations II: pilot study of a new system. BMC Health Serv Res. 2005;5:25
  20. Guyatt GH, Oxman AD, Vist GE, Kunz R, Falck-Ytter Y, Alonso-Coello P, et al. GRADE: an emerging consensus on rating quality of evidence and strength of recommendations. BMJ. 2008;336:924–926
  21. Keus F, Wetterslev J, Gluud C, Gooszen HG, van Laarhoven CJHM. Robustness assessments are needed to reduce bias in meta-analyses including zero-event randomized trials. Am J Gastroenterol 2009;104:546–51.
  22. Bradburn MJ, Deeks JJ, Berlin JA, Russell Localio A. Much ado about nothing: a comparison of the performance of meta-analytical methods with rare events. Stat Med. 2007;26:53–77
  23. Sweeting MJ, Sutton AJ, Lambert PC. What to add to nothing? Use and avoidance of continuity corrections in meta-analysis of sparse data. Stat Med. 2004;23:1351–1375
  24. Agresti A. An introduction to categorical data analysis. New York, NY: Wiley and Sons; 1996;
  25. Gluud LL. Bias in clinical intervention research. Am J Epidemiol. 2006;163:493–501
  26. Higgins JPT, Green S, editors. Cochrane Handbook for Systematic Reviews of Interventions 5.0.1 [updated September 2008]. The Cochrane Collaboration, 2008. Available at: www.cochrane-handbook.org.
  27. Berkey CS, Mosteller F, Lau J, Antman EM. Uncertainty of the time of first significance in random effects cumulative meta-analysis. Control Clin Trials. 1996;17:357–371
  28. Trikalinos TA, Churchill R, Ferri M, Leucht S, Tuunainen A, Wahlbeck K, et al. Effect sizes in cumulative meta-analyses of mental health randomized trials evolved over time. J Clin Epidemiol. 2004;57:1124–1130
  29. Ioannidis JP. Contradicted and initially stronger effects in highly cited clinical research. JAMA. 2005;294:218–228
  30. Ros A, Gustafsson L, Krook H, Nordgren CE, Thorell A, Wallin G, et al. Laparoscopic cholecystectomy versus mini-laparotomy cholecystectomy: a prospective, randomized, single-blind study. Ann Surg. 2001;234:741–749
  31. Bruce DM, Smith M, Walker CB, Heys SD, Binnie NR, Gough DB, et al. Minimal access surgery for cholelithiasis induces an attenuated acute phase response. Am J Surg. 1999;178:232–234
  32. Sutton AJ, Cooper NJ, Jones DR, Lambert PC, Thompson JR, Abrams KR. Evidence-based sample size calculations based upon updated meta-analysis. Stat Med. 2007;26:2479–2500
  33. O'Neill RT. Secondary endpoints cannot be validly analyzed if the primary endpoint does not demonstrate clear statistical significance. Control Clin Trials. 1997;18:550–556
  34. Guyatt GH, Mills EJ, Elbourne D. In the era of systematic reviews, does the size of an individual trial still matter. PLoS Med. 2008;5:e4

 Funding: No funding was obtained for this study. All researchers were dependent on funding.

 Conflict of interest: All authors declare that there are no personal interests, no competing interests, and no funding interests. Therefore, the authors have nothing to declare.

 Guarantor of the article: F. Keus and J. Wetterslev had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.

PII: S0895-4356(09)00278-9

doi: 10.1016/j.jclinepi.2009.08.023

Journal of Clinical Epidemiology
Volume 63, Issue 3 , Pages 246-256 , March 2010

Article Tools

* Image Usage & Resolution