Article Text

Download PDFPDF
A cautious approach to interpreting retrospective data
  1. Kamron N Khan1,2,
  2. Rubina Rahman2
  1. 1 Department of ophthalmology, Leeds Institute of Molecular Medicine, Leeds, UK
  2. 2 Department of ophthalmology, Calderdale Royal Infirmary, Halifax, UK
  1. Correspondence to Dr Kamron N Khan PhD, Department of ophthalmology, Leeds Institute of Molecular Medicine, Leeds ls97tf, UK; medknk{at}

Statistics from

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.

The recent article of Yiu et al 1 aims to compare the functional and anatomical outcomes after idiopathic epiretinal membrane (ERM) surgery either ‘alone’ or when ‘combined’ with a cataract surgery. We feel that the design of this study is fundamentally flawed, however. In order to adequately compare these groups, the ‘alone’ group should remain phakic for the duration of the study. In this paper, the ‘alone’ group were already pseudophakic in 67.5% of cases (27/40) at recruitment, and a further 10% received surgery for lens opacification at a separate date. The authors have, therefore, compared single session combined surgery with sequential individual surgery (primary cataract surgery with late ERM peeling) in 77.5% of cases. Furthermore, all …

View Full Text


  • Contributors Both KNK and RR contributed to the writing of this paper.

  • Competing interests None.

  • Provenance and peer review Not commissioned; internally peer reviewed.