Update of a meta-analysis on lung cancer and welding

Scand J Work Environ Health. 2006 Feb;32(1):22-31. doi: 10.5271/sjweh.973.


Objectives: This study is an update, over the period 1954-2004, of a previous meta-analysis completed in 1994. It was aimed at assessing lung cancer risk among welders, while addressing heterogeneity, publication bias, and confounding issues.

Methods: Combined relative risks (CRR) and their variances were calculated using fixed and random effects models. Heterogeneity was tested using the Q statistic. The publication bias was estimated using funnel plots, and Egger's regression and partially controlled by excluding studies with positive reporting bias.

Results: The literature provided 60 studies eligible for the meta-analysis. No heterogeneity was observed. The fixed effect CRR for all of the welders and all of the studies was 1.26 (95% CI 1.20-1.32) after partial control of publication bias. No difference was observed according to welding activities. Smoking did not appear to be a marked confounder in the relationship between lung cancer and welding, but the effect of asbestos could not be assessed.

Conclusions: The meta-analysis showed a 26% excess of lung cancer for welders without any difference according to welding activities.

Publication types

  • Meta-Analysis

MeSH terms

  • Americas / epidemiology
  • Case-Control Studies
  • Europe / epidemiology
  • Humans
  • Lung Neoplasms / epidemiology*
  • Lung Neoplasms / etiology
  • Lung Neoplasms / mortality
  • Welding / statistics & numerical data*