Confounding: What is it and how do we deal with it?

Confounding: What is it and how do we deal with it?

Can J Surg 2012;55(2):132-138 | PDF

Luis Henrique P. Braga, MD, MSc, PhD*† Forough Farrokhyar, MPhil, PhD*‡ Mohit Bhandari, MD, PhD*‡§

From the *Department of Surgery, the †Division of Urology, the ‡Department of Clinical Epidemiology and Biostatistics and the §Division of Orthopaedic Surgery, McMaster University, Hamilton, Ont.


This article explores the potential benefits and defined risks associated with prophylactic surgical procedures for astronauts before extended-duration space flight. This includes, but is not limited to, appendectomy and cholecystesctomy. Furthermore, discussion of treatment during space flight, potential impact of an acute illness on a defined mission and the ethical issues surrounding this concept are debated in detail.


Cet article explore les avantages possibles et les risques définis associés à des interventions chirurgicales prophylactiques (notamment appendicectomie et cholécystectomie) chez les astronautes devant effectuer des séjours prolongés dans l’espace. Le traitement pendant le séjour dans l’espace, les répercussions éventuelles d’une maladie grave au cours d’une mission particulière et les enjeux éthiques entourant la question y sont débattus en profondeur.

Accepted for publication Dec. 21, 2011

Competing interests:M. Bhandari was funded, in part, by a Canada Research Chair, McMaster University. None declared for L.H.P. Braga and F. Farrokhyar.

DOI: 10.1503/cjs.036311

Correspondence to: L.H.P. Braga, Division of Urology, Department of Surgery, McMaster University, 1280 Main St. W, Hamilton ON L8S 4K1;