Tobacco smoking and gastric cancer: meta-analyses of published data versus pooled analyses of individual participant data (StoP Project).

Ferro, A. et al. (2018) Tobacco smoking and gastric cancer: meta-analyses of published data versus pooled analyses of individual participant data (StoP Project). European Journal of Cancer Prevention, 27(3), pp. 197-204. (doi: 10.1097/CEJ.0000000000000401) (PMID:29595756)

Abstract

Tobacco smoking is one of the main risk factors for gastric cancer, but the magnitude of the association estimated by conventional systematic reviews and meta-analyses might be inaccurate, due to heterogeneous reporting of data and publication bias. We aimed to quantify the combined impact of publication-related biases, and heterogeneity in data analysis or presentation, in the summary estimates obtained from conventional meta-analyses. We compared results from individual participant data pooled-analyses, including the studies in the Stomach Cancer Pooling (StoP) Project, with conventional meta-analyses carried out using only data available in previously published reports from the same studies. From the 23 studies in the StoP Project, 20 had published reports with information on smoking and gastric cancer, but only six had specific data for gastric cardia cancer and seven had data on the daily number of cigarettes smoked. Compared to the results obtained with the StoP database, conventional meta-analyses overvalued the relation between ever smoking (summary odds ratios ranging from 7% higher for all studies to 22% higher for the risk of gastric cardia cancer) and yielded less precise summary estimates (SE ≤2.4 times higher). Additionally, funnel plot asymmetry and corresponding hypotheses tests were suggestive of publication bias. Conventional meta-analyses and individual participant data pooled-analyses reached similar conclusions on the direction of the association between smoking and gastric cancer. However, published data tended to overestimate the magnitude of the effects, possibly due to publication biases and limited the analyses by different levels of exposure or cancer subtypes.

• Item Type: Articles
• Additional Information: This study was funded by FEDER through the Operational Programme Competitiveness and Internationalization and national funding from the Foundation for Science and Technology – FCT (Portuguese Ministry of Science, Technology and Higher Education) under the Unidade de Investigação em Epidemiologia – Instituto de Saúde Pública da Universidade do Porto (EPI Unit) (POCI-01- 0145-FEDER-006862; ref. UID/DTP/04750/2013); the PhD Grants PD/BD/105823/2014 (Ana Ferro) and SFRH/BD/ 102585/2014 (Samantha Morais) and the Postdoc grant SFRH/BPD/108751/2015 (Bárbara Peleteiro) co-funded by FCT and the POPH/FSE Program, and by the Italian Ministry of Health (Young Researchers, GR-2011-02347943 to Stefania Boccia), the Fondazione Italiana per la Ricerca sul Cancro (FIRC), and the Associazione Italiana per la Ricerca sul Cancro, project no. 16715 (investigator grant). Matteo Rota was supported by a fellowship from FIRC.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Derakhshan, Professor Mohammad
• Authors: Ferro, A., Morais, S., Rota, M., Pelucchi, C., Bertuccio, P., Bonzi, R., Galeone, C., Zhang, Z.-F., Matsuo, K., Ito, H., Hu, J., Johnson, K. C., Yu, G.-P., Palli, D., Ferraroni, M., Muscat, J., Malekzadeh, R., Ye, W., Song, H., Zaridze, D., Maximovitch, D., Aragonés, N., Castaño-Vinyals, G., Vioque, J., Navarrete-Muñoz, E. M., Pakseresht, M., Pourfarzi, F., Wolk, A., Orsini, N., Bellavia, A., Håkansson, N., Mu, L., Pastorino, R., Kurtz, R. C., Derakhshan, M. H., Lagiou, A., Lagiou, P., Boffetta, P., Boccia, S., Negri, E., La Vecchia, C., Peleteiro, B., and Lunet, N.
• College/School: College of Medical Veterinary and Life Sciences > School of Infection & Immunity
• Journal Name: European Journal of Cancer Prevention
• Publisher: Lippincott Williams & Wilkins
• ISSN: 0959-8278
• ISSN (Online): 1473-5709
• Copyright Holders: Copyright © 2018 Wolters Kluwer Health, Inc.
• First Published: First published in European Journal of Cancer Prevention 27(3):197-204
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher