The evidence strength of a meta-analysis of aspirin for primary prevention of cancer

  • Qibiao WuEmail author
  • Elaine Laihan Leung
Letter to the Editor


Dr. Tarek Haykal et al. (145:1795–1809, 2019) reported a meta-analysis of aspirin for the primary prevention of cancer in individuals without known cancer. The authors found that aspirin use was not associated with significant reduction in cancer mortality or incidence, but with higher rates of bleeding. The findings of this study added some evidence to the clinical practice. However, several issues might have compromised the strength of the evidence of this systematic review. If the investigators could have further clarified the inclusion and exclusion criteria, included all eligible studies, extracted data more meticulously, and performed more necessary sensitivity analyses to confirm the robustness of their findings, the strength of evidence of this meta-analysis would have been stronger.


Letter to the editors Evidence Strength Meta-analysis Aspirin Primary prevention Cancer 



This work was funded by The Science and Technology Development Fund, Macau SAR (File No. 130/2017/A3, 0099/2018/A3, 0096/2018/A3).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.State Key Laboratory of Quality Research in Chinese Medicine, Faculty of Chinese Medicine, Macau Institute for Applied Research in Medicine and HealthMacau University of Science and TechnologyMacauChina

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