Intended for healthcare professionals

Letters News story on Tamiflu study

Mark Jones’s reply to Myles and Leonardi-Bee’s response to his critique of their paper reported in The BMJ

BMJ 2014; 348 doi: (Published 30 April 2014) Cite this as: BMJ 2014;348:g3001
  1. Mark Jones, statistician1
  1. 1University of Queensland, Brisbane, Australia
  1. m.jones{at}

Thank you for the explanation of how you conducted your time dependent analysis.1 2 It is now clear why you obtained such a biased estimate of treatment effect. By ignoring the time before treatment with a neuraminidase inhibitor you have increased the immortal time bias, not eliminated it. In fact, you did not include treatment as a time dependent exposure—you just began the follow-up at different points in time for each treatment group. You failed to take into account that patients in both treatment groups needed to survive long enough to reach hospital. Once they reached …

View Full Text

Log in

Log in through your institution


* For online subscription