You are here

Article Text

Article menu
Download PDFPDF
PostScript
Letter
Case–control or cohort study?
  1. Tamhane Ashutosh,
  2. Gerald McGwin
  1. Department of Epidemiology, The University of Alabama at Birmingham, Birmingham, Alabama, USA
  1. Correspondence to Ashutosh Tamhane, 1665 University blvd, RPHB 514-A, Birmingham, AL 35294, USA; tamhane{at}uab.edu

http://dx.doi.org/10.1136/bjo.2011.203141

Statistics from Altmetric.com

    Request Permissions

    If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

    In a recently published article by Chandra et al the authors have stated that they conducted a ‘case-controlled’ study to examine the anticoagulant effect of warfarin in vitreoretinal surgery.1 However, this study was conducted on a cohort of patients receiving pars plana vitrectomy (PPV); 60 patients who received warfarin (exposure) on the day of …

    View Full Text

    Footnotes

    • Competing interests None.

    • Provenance and peer review Not commissioned; not externally peer reviewed.