In a meta-analysis the literature base is thoroughly searched for experimental
and correlational studies that are relevant to the investigation. These
studies become the data base for the subsequent analysis. Studies reporting
on the reliability of the measures used in the various studies and their
standard deviations (for range deviation adjustments) in either or both
variables are included in this database.
Once the study database is assembled, the next step is to convert the individual
study statistic to a common metric for later accumulation. Table 1
shows several of the more common methods of converting the individual study
statistic to r.