Qu, J., Yang, J., Chen, M., Cui, L., Wang, T., Gao, W., Tian, J. and Wei, R. 2019. MicroRNA-21 as a diagnostic marker for hepatocellular carcinoma: A systematic review and meta-analysis: MiR-21 in HCC. Pakistan Journal of Medical Sciences. 35, 5 (Aug. 2019). DOI:https://doi.org/10.12669/pjms.35.5.685.