Limitations of the present study should be considered. Publication bias may result from the fact that unpublished data, as well as papers published in languages other than English and Chinese, were not included. Further, our meta-analysis division criteria of ethnic groups into “Caucasian,” or “Asian” may bias the results, without the detailed knowledge of the patients. Another limitation in our meta-analysis is the small sample size. Despite these limitations, we quantified and analyzed previous inconsistent results from previous studies in our meta-analysis. Besides, the number of years of publication, race, sample origin, disease, genotyping, male ratio, and average age were not heterogeneous factors in this study, which indicates a more credible conclusion of the relationship between ENPP1 genetic polymorphism and CHD in our results.
The authors would like to give our appreciation to the reviewers for their helpful comments.
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