Corrigendum to: “Publication bias and time-trend bias in meta-analysis of bicycle helmet efficacy: a re-analysis of Attewell, Glase and McFadden, 2001” [Accid. Anal. Prev. 43 (2011) 1245–1251].

This paper is a corrigendum to the previously published paper: “Publication bias and time-trend bias in meta-analysis of bicycle helmet efficacy: A re-analysis of Attewell, Glase and McFadden, 2001” [Accid. Anal. Prev. (2011) 1245–1251]. This corrigendum was prepared to correct errors in data and analysis in the previously published paper. Like the previously published paper, this paper confirms that the meta-analysis of bicycle helmet efficacy reported by Attewell, Glase and McFadden (Accident Analysis and Prevention, 2001, 345–352) was influenced by publication bias and time-trend bias that was not controlled for. As a result, the analysis reported inflated estimates of the effects of bicycle helmets. This paper presents a re-analysis of the study. The re-analysis included: (1) Ensuring the inclusion of all published studies by means of continuity corrections of estimates of effect relying on zero counts; (2) detecting and adjusting for publication bias by means of the trim-and-fill method; (3) detecting and trying to account for a time-trend bias in estimates of the effects of bicycle helmets; (4) updating the study by including recently published studies evaluating the effects of bicycle helmets. The re-analysis shows smaller safety benefits associated with the use of bicycle helmets than the original study.

[1]  Alexander J Sutton,et al.  What to add to nothing? Use and avoidance of continuity corrections in meta-analysis of sparse data. , 2004, Statistics in medicine.

[2]  M. S. Patel,et al.  An introduction to meta-analysis. , 1989, Health Policy.

[3]  K. Heng,et al.  Helmet use and bicycle-related trauma in patients presenting to an acute hospital in Singapore. , 2006, Singapore medical journal.

[4]  Richard L. Tweedie,et al.  A Non-parametric "Trim and Fill" Method of Assessing Publication Bias in Meta-analysis , 1998 .

[5]  Julia H. Littell,et al.  Systematic Reviews and Meta-Analysis , 2008 .

[6]  Rune Elvik,et al.  The Handbook of Road Safety Measures , 2009 .

[7]  R G Attewell,et al.  Bicycle helmet efficacy: a meta-analysis. , 2001, Accident; analysis and prevention.

[8]  R. Tweedie,et al.  A Nonparametric “Trim and Fill” Method of Accounting for Publication Bias in Meta-Analysis , 2000 .

[9]  Elizabeth M. L. Towner,et al.  BICYCLE HELMETS - A REVIEW OF THEIR EFFECTIVENESS: A CRITICAL REVIEW OF THE LITERATURE , 2002 .

[10]  J. Sterne,et al.  Funnel plots for detecting bias in meta-analysis: guidelines on choice of axis. , 2001, Journal of clinical epidemiology.

[11]  K. Hansen,et al.  Protective Effect of Different Types of Bicycle Helmets , 2003, Traffic injury prevention.

[12]  Julian P T Higgins,et al.  Systematic reviews and metaanalysis , 1997 .

[13]  S Duval,et al.  Trim and Fill: A Simple Funnel‐Plot–Based Method of Testing and Adjusting for Publication Bias in Meta‐Analysis , 2000, Biometrics.

[14]  M. Borenstein,et al.  Publication Bias in Meta-Analysis: Prevention, Assessment and Adjustments , 2006 .

[15]  Rune Elvik,et al.  Can We Trust the Results of Meta-Analyses?: A Systematic Approach to Sensitivity Analysis in Meta-Analyses , 2005 .

[16]  D. L. Robinson,et al.  Bicycle helmet legislation: can we reach a consensus? , 2007, Accident; analysis and prevention.

[17]  W Hausotter Fahrradunfaelle mit und ohne Fahrradhelm , 2000 .

[18]  Wolfgang Viechtbauer,et al.  Publication bias in meta-analysis: Prevention, assessment and adjustments , 2007, Psychometrika.

[19]  D. Thompson,et al.  Epidemiology of bicycle injuries and risk factors for serious injury. , 1997, Injury prevention : journal of the International Society for Child and Adolescent Injury Prevention.

[20]  F P Rivara,et al.  Helmets for preventing head and facial injuries in bicyclists. , 2000, The Cochrane database of systematic reviews.

[21]  D. Thompson,et al.  Cochrane Review : Helmets for preventing head and facial injuries in bicyclists , 2017 .

[22]  Sue Duval,et al.  The Trim and Fill Method , 2006 .