  An ongoing "reproducibility crisis" calls into question scientific
discoveries across a variety of disciplines ranging from life to social
sciences. Replication studies aim to investigate the validity of findings in
published research, and try to assess whether the latter are statistically
consistent with those in the replications. While the majority of replication
projects are based on a single experiment, multiple independent replications of
the same experiment conducted simultaneously at different sites are becoming
more frequent. In connection with these types of projects, we deal with testing
heterogeneity among sites; specifically, we focus on sample size determination
suitable to deliver compelling evidence once the experimental data are
gathered.
