Points of time, investigated mediums, methods of analysis, and reporting of results of metal ion measurement in included RCTs.

Studies were summarized due to multiple reporting of identical patient population.2: Incl. all kinds of metal ion measurement in urin, e.g. 12- or 24 h urine.3: AAS = All procedures of atomic absorption spectrometry.4: ICP-MS = all procedures of inductively coupled plasma mass spectrometry.n. r. = Not reported.SD: Standard deviation; SEM: Standard error of the mean; IQR: Interquartile range.Metal ion concentration in RCTs.