Discussion on the selection of effect size in meta-analysis
We read with great interest the recent published study by Zhao and colleagues entitled “The effect of health education on the quality of life of postoperative patients with gastric cancer: a systematic review and meta-analysis” (1). They performed a systematic review and meta-analysis to assess the effect of health education on postoperative quality of life in patients with gastric cancer and confirmed that health education can significantly improve patients’ quality of life. We appreciate Zhao and colleagues for the valuable work, however, after a careful learning of the literature, we would like to pay attention to some important missing aspects in the study.
Concerning the effect size in the study, the odds ratio (OR) was used when the scores of quality of life and physical, role, emotional, cognitive, and social function were compared between health education group and control group. However, the scores were continuous variable, and mean difference (MD) should be applied when comparison was performed between health education group and control group. Actually, MD is showed in every forest plot in this meta-analysis and OR is suitable for binary variable (2). Moreover, in the method section, sensitivity analysis was introduced. But, in this meta-analysis, results of the sensitivity analysis were not reported in the main text. Therefore, we believe that this study is required to further revise.
We make these comments only to recommend that the authors of similar such studies may consider these comments.
Acknowledgments
Funding: None.
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References
- Zhao G, Zhang Y, Liu C. The effect of health education on the quality of life of postoperative patients with gastric cancer: a systematic review and meta-analysis. Ann Palliat Med 2021;10:10633-42. [Crossref] [PubMed]
- Wu J, Jin Y, Sun X. Is magnetic resonance elastography superior to transient elastography for the diagnosis of liver fibrosis? Ann Palliat Med 2021;10:12917-8. [Crossref] [PubMed]
