Table 6. Information of search methods and criteria of inclusion and exclusion.

Methods	Information
Search strategy	4 search engines, including PubMed, EMBASE, Web of Science and Cochrane Database of Systematic Reviews
Search deadline	15 April, 2017
Search terms	mir and hepatocellular carcinoma
Inclusion criteria	(1) Patients with hepatocellular carcinoma; (2) Expression of miRNAs and survival outcome in tissue, plasma or serum were measured; (3) At least, one of survival curves about overall survival (OS), cause-specific survival (CSS), disease-free survival (DFS), recurrence-free survival (RFS), progression-free survival (PFS) and metastasis-free survival (MFS) was measured, with or without the HR or 95% CI; (4) Full text articles published in English
Exclusion criteria	(1) Reviews, letters or laboratory studies without original data and retracted articles; (2) Frequency of studies estimating prognostic value of miRNAs ≤ 2 in tissue; (3) Studies which cannot be merged; (4) If more than one article had been published on the identical study cohort, only the most comprehensive study was selected for the present meta-analysis