Evidence bicycle helmets mitigate intra-cranial injury is not controversial

  • J. OlivierEmail author
  • P. Creighton
  • C. T. Mason
Letter to the Editor

A recently published article questions the protective effect of bicycle helmets against intra-cranial injury [1]. In a case–control study design, Joseph and colleagues analyze data from cycling presentations from a collision or fall to a level 1 trauma center with an initial head computed tomography (CT) scan.

There are several inconsistencies and analytic errors in the analysis by Joseph and colleagues. This includes (1) a selection bias by limiting presentations to cyclists with a suspected head injury, (2) statistical results for intra-cranial hemorrhage that could not have arisen from the reported data, (3) failure to analyze intra-cranial injury as defined by the authors, (4) over-reliance on pvalues and the fallacy of accepting the null hypothesis, (5) simple numerical errors, and (6) incorrect reporting of previous literature. We discuss each of these issues in turn. When it is possible to correct these errors using the data reported, we have re-analyzed the data. The lead...


Lead Author Neck Injury Report Odds Ratio Lower Confidence Limit Initial Head 
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Compliance with ethical standards

Conflict of interest

Jake Olivier, Prudence Creighton and C. Thomas Mason declare they have 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

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  1. 1.School of Mathematics and StatisticsUniversity of New South WalesSydneyAustralia
  2. 2.University of ArizonaTucsonUSA

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