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Subgroup Analyses in Surgery

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Evidence-Based Surgery

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Abstract

Evidence for surgical practice should be based on high-quality data, some of which would originate from well-designed and executed randomized controlled trials (RCTs). Subgroup analyses are often reported within RCT results and they aim to identify either consistencies or large differences in different categories (or subgroups) of patients. However, subgroup analyses can sometimes be misleading. The purpose of this article is to outline the criteria for rigorous subgroup analyses in methodologically sound RCTs. A clinical scenario based upon a recent RCT in general surgery will support these criteria throughout the text.

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References

  1. Sun X, Ioannidis JP, Agoritsas T, Alba AC, Guyatt G. How to use a subgroup analysis: users’ guide to the medical literature. JAMA. 2014;311:405–11.

    Article  CAS  Google Scholar 

  2. Sun X, Briel M, Busse JW, You JJ, Akl EA, Mejza F, Bala MM, Bassler D, Mertz D, Diaz-Granados N, Vandvik PO, Malaga G, Srinathan SK, Dahm P, Johnston BC, Alonso-Coello P, Hassouneh B, Walter SD, Heels-Ansdell D, Bhatnagar N, Altman DG, Guyatt GH. Credibility of claims of subgroup effects in randomised controlled trials: systematic review. BMJ. 2012;344:e1553.

    Article  Google Scholar 

  3. ISIS-2 (Second International Study of Infarct Survival) Collaborative Group. Randomised trial of intravenous streptokinase, oral aspirin, both, or neither among 17,187 cases of suspected acute myocardial infarction: ISIS-2. Lancet 1988;2:349–60.

    Google Scholar 

  4. Tsujinaka T, Yamamoto K, Fujita J, Endo S, Kawada J, Nakahira S, Shimokawa T, Kobayashi S, Yamasaki M, Akamaru Y, Miyamoto A, Mizushima T, Shimizu J, Umeshita K, Ito T, Doki Y, Mori M. Subcuticular sutures versus staples for skin closure after open gastrointestinal surgery: a phase 3, multicentre, open-label, randomised controlled trial. Lancet. 2013;382:1105–12.

    Article  Google Scholar 

  5. Sun X, Briel M, Walter SD, Guyatt GH. Is a subgroup effect believable? Updating criteria to evaluate the credibility of subgroup analyses. BMJ. 2010;340:c117.

    Article  Google Scholar 

  6. Dijkman B, Kooistra B, Bhandari M. Evidence-based surgery working group. How to work with a subgroup analysis. Can J Surg. 2009;52:515–22.

    Google Scholar 

  7. Oxman AD, Guyatt GH. A consumer’s guide to subgroup analyses. Ann Intern Med. 1992;116:78–84.

    Article  CAS  Google Scholar 

  8. Rothwell PM. Treating individuals 2. Subgroup analysis in randomised controlled trials: importance, indications, and interpretation. Lancet 2005;365:176–86.

    Google Scholar 

  9. Guyatt G, Wyer P, Ioannidis J. When to believe a subgroup analysis. In: Guyatt G, Drummond R, Meade MO, et al., editors. User’s guides to the medical literature: a manual for evidence-based clinical practice. 2nd ed. Toronto (ON): McGraw-Hill; 2008. p. 571–93.

    Google Scholar 

  10. Buyse ME. Analysis of clinical trial outcomes: some comments on subgroup analyses. Control Clin Trials. 1989;10:187S–94S.

    Article  CAS  Google Scholar 

  11. Sun X, Heels-Ansdell D, Sprague S, Bandhari M, Walter SD, Sanders D, Schemitsch E, Tornetta P III, Swiontkowski M, Guyatt G. Is a subgroup claim believable? A user’s guide to subgroup analyses in the surgical literature. J Bone Joint Surg Am. 2011;93:e8.

    Article  Google Scholar 

  12. Yusuf S, Wittes J, Probstfield J, Tyroler HA. Analysis and interpretation of treatment effects in subgroups of patients in randomized clinical trials. JAMA. 1991;266:93–8.

    Article  CAS  Google Scholar 

  13. Brookes ST, Whitely E, Egger M, Smith GD, Mulheran PA, Peters TJ. Subgroup analyses in randomized trials: risks of subgroup-specific analyses; power and sample size for the interaction test. J Clin Epidemiol. 2004;57:229–36.

    Article  Google Scholar 

  14. Kernan WN, Viscoli CM, Makuch RW, Brass LM, Horwitz RI. Stratified randomization for clinical trials. J Clin Epidemiol. 1999;52:19–26.

    Article  CAS  Google Scholar 

  15. Sun X, Briel M, Busse JW, You JJ, Akl EA, Mejza F, Bala MM, Bassler D, Mertz D, Diaz-Granados N, Vandvik PO, Malaga G, Srinathan SK, Dahm P, Johnston BC, Alonso-Coello P, Hassouneh B, Truong J, Dattani ND, Walter SD, Heels-Ansdell D, Bhatnagar N, Altman DG, Guyatt GH. The influence of study characteristics on reporting of subgroup analyses in randomised controlled trials: systematic review. BMJ. 2011;342:d1569.

    Article  Google Scholar 

  16. Furukawa TA. From effect size into number needed to treat. Lancet. 1999;353:1680.

    Article  CAS  Google Scholar 

  17. Schmid CH, Lau J, McIntosh MW, Cappelleri JC. An empirical study of the effect of the control rate as a predictor of treatment efficacy in meta-analysis of clinical trials. Stat Med. 1998;17:1923–42.

    Article  CAS  Google Scholar 

  18. Assmann SF, Pocock SJ, Enos LE, Kasten LE. Subgroup analysis and other (mis)uses of baseline data in clinical trials. Lancet. 2000;355:1064–9.

    Article  CAS  Google Scholar 

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Author information

Authors and Affiliations

  1. Department of Surgery, Division of Plastic Surgery, McMaster University, Hamilton, ON, Canada

    Alexandra Hatchell & Sophocles H. Voineskos

Authors
  1. Alexandra Hatchell
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  2. Sophocles H. Voineskos
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Corresponding author

Correspondence to Sophocles H. Voineskos .

Editor information

Editors and Affiliations

  1. Department of Surgery, Division of Plastic Surgery, Department of Health Research Methods, Evidence and Impact (HEI), McMaster University, Hamilton, ON, Canada

    Achilles Thoma

  2. Department of Surgery, Division of Orthopaedic Surgery, Department of Health Research Methods, Evidence and Impact (HEI), McMaster University, Hamilton, ON, Canada

    Sheila Sprague

  3. Department of Surgery, Division of Plastic Surgery, McMaster University, Hamilton, ON, Canada

    Sophocles H. Voineskos

  4. Department of Health Research Methods, Evidence and Impact (HEI), McMaster University, Hamilton, ON, Canada

    Charles H. Goldsmith

Appendix 1

Appendix 1

Search results for the following search strategy: “subcuticular suture AND staple AND gastrointestinal surgery AND infection AND scar AND randomized controlled trials”.

  1. 1.

    Tsujinaka T, Yamamoto K, Fujita J, Endo S, Kawada J, Nakahira S, Shimokawa T, Kobayashi S, Yamasaki M, Akamaru Y, Miyamoto A, Mizushima T, Shimizu J, Umeshita K, Ito T, Doki Y, Mori M. Subcuticular sutures versus staples for skin closure after open gastrointestinal surgery: a phase 3, multicentre, open-label, randomized controlled trial. Lancet. 2013;382:1105–12.

  2. 2.

    Tanaka A, Sadahiro S, Suzuki T, Okada K, Saito G. Randomized controlled trial comparing subcuticular absorbable suture with conventional interrupted suture for wound closure at elective operation of colon cancer. Surgery. 2014;155(3):486–92.

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Hatchell, A., Voineskos, S.H. (2019). Subgroup Analyses in Surgery. In: Thoma, A., Sprague, S., Voineskos, S., Goldsmith, C. (eds) Evidence-Based Surgery. Springer, Cham. https://doi.org/10.1007/978-3-030-05120-4_30

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  • DOI: https://doi.org/10.1007/978-3-030-05120-4_30

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  • Publisher Name: Springer, Cham

  • Print ISBN: 978-3-030-05119-8

  • Online ISBN: 978-3-030-05120-4

  • eBook Packages: MedicineMedicine (R0)

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