2.1. | Search strategy
Systematic search was conducted within the PubMed/Medline, Scopus, ISI Web of Science, EMBASE and Google Scholar up to June 2020 with English language restriction for identifying eligible studies.
The following combination of search terms was used (Silymarin[tiab] OR silimarin[tiab] OR SIL[tiab] OR ”milk thistle”[tiab] OR Silybum[tiab] OR Silymarina[tiab] OR Silimarina[tiab] OR Silymarin[Mesh] OR ”Milk Thistle”[Mesh]) AND (berberine[tiab] OR BBR[tiab] OR Berberis[tiab] OR Berberina[tiab] OR Berberol[tiab] OR Berberine[Mesh] OR Berberis[Mesh]) AND (”liver enzyme”[tiab] OR ”liver enzymes”[tiab] OR ”Liver function”[tiab] OR aminotransferase[tiab] OR ALT[tiab] OR ”alanine aminotransferase”[tiab] OR ”Alanine Transaminase”[tiab] OR ”serum glutamic-pyruvic transaminase”[tiab] OR SGPT[tiab] OR AST[tiab] OR ”Aspartate Aminotransferases”[tiab] OR ”Aspartate transaminase”[tiab] OR SGOT[tiab] OR ”serum glutamic-oxaloacetic transaminase”[tiab] OR ALP[tiab] OR ”Alkaline phosphatase”[tiab] OR GGT[tiab] OR ”gamma-Glutamyltransferase”[tiab] OR ”Liver Function Tests”[Mesh] OR ”Alanine Transaminase”[Mesh] OR ”Aspartate Aminotransferases”[Mesh] OR ”Alkaline Phosphatase”[Mesh] OR ”gamma-Glutamyltransferase”[Mesh]). Literature searches were downloaded into EndNote (version X8, for Windows, Thomson Reuters, Philadelphia, PA, USA) to begin the review process.