Letter to the Editor: “Technical performance of shear wave elastography for measuring liver stiffness in pediatric and adolescent patients: a systematic review and meta-analysis”
by Jie Wei, Mingyang Jiang, Huachu Deng, Dong Hong Deng (email@example.com)Technical performance of shear wave elastography for measuring liver stiffness in pediatric and adolescent patients: a systematic review and meta-analysis
We read the paper by Kim et al.  with interest. The authors performed a meta-analysis with 36 studies that met the inclusion criteria, providing data for 5429 patients to assess the technical performance (proportion of technical failure and unreliable measurements) of shear wave elastography (SWE) for assessing liver stiffness in pediatric and adolescent patients. They concluded that echnical erformance of SWE, especially the rate of unreliable measurements from TE studies and rates of technical failure from pSWE and 2D-SWE studies. Considering the importance of technical performance for clinical validation of SWE, numbers of and reasons for technical failure and unreliable measurements should be reported in future studies. Further efforts are necessary to standardize SWE reliability criteria. After carefully reading, we wish to put forth the following suggestion.
Repeatedly including the same study population will affect the total sample size and the number of participants in each group; thus, duplicated studies using the same study population should not be included in a meta-analysis. However, we found that data from several studies may have by error been included twice due to reporting of different aspects of the study in separate publications, which significantly affect the reliability of the results. For instance, the studies in the references 23 and 24 included for the characteristics of included trial comparisons, were conducted by the same group of authors, the participants are from the same country, have the same number of participants. Hence, we suspect that these are two duplicate studies. Therefore, we suspect that this article might include more of the same studies and the same patients. The authors should formulate strict inclusion and exclusion criteria, eliminate duplicate documents that employ the same study population, and select the ones with the best quality or the largest sample size for analysis.