AMSTAR is an instrument to assess the methodological quality of systematic reviews, building upon previous tools, empirical evidence and expert consensus.
Reference:
Shea, B. J., Grimshaw, J. M., Wells, G. A., Boers, M., Andersson, N., Hamel, C., ... & Bouter, L. M. (2007). Development of AMSTAR: a measurement tool to assess the methodological quality of systematic reviews. BMC medical research methodology, 7(1), 1-7.
