Always randomize as late as possible

  • Erik van WerkhovenEmail author
  • Parvin Tajik
  • Patrick M. Bossuyt
Letter to the Editor


Compliance with ethical standards

Conflict of interest

Erik van Werkhoven declares that he has no conflict of interest. Parvin Tajik declares that she has no conflict of interest. Patrick M. Bossuyt declares that he has no conflict of interest.

Ethical approval

This article does not contain any studies with human participants or animals performed by any of the authors.


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Copyright information

© The International Gastric Cancer Association and The Japanese Gastric Cancer Association 2019

Authors and Affiliations

  1. 1.Department of Clinical Epidemiology, Biostatistics and BioinformaticsAmsterdam UMC, University of AmsterdamAmsterdamThe Netherlands
  2. 2.Department of PathologyAmsterdam UMC, University of AmsterdamAmsterdamThe Netherlands

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