LAUSR

In a meta-analysis of ds, the utility of converting d to a point-biserial correlation (rpb), correcting rpb for study artifacts, and then converting rpb back to d depends on how accurately the d to rpb-rpb to d (dr-rd) method reproduces the original uncorrected ds. This study compared test ds (dt) converted to dr-rd ds to control ds (dc) to determine the dr-rd formula combinations with the least bias, defined as the difference between dr-rd ds and dc. dt were calculated with available conversion and rpb correction formulas at various base rates and SD ratios, whereas dc were calculated without conversion formulas at base rate .50 and SD ratio 1.00. Results showed that the lowest bias formula combinations reproduced dc at SD ratio 1.00, bias increased as SD ratio decreased, and formula combinations that produced the lowest bias values were, on average, more accurate than formula combinations that produced the next to lowest bias values. Findings provide the lowest bias dr-rd formula combinations for artifact-corrected meta-analyses of studies using the two independent-groups design.