| ROI-based meta-analyses | Voxel-based meta-analyses | |||
---|---|---|---|---|---|
 |  | KDA/old ALE | Multilevel KDA/new ALE | SDM | ES-SDM |
Selection of studies | Â | Â | Â | Â | Â |
   Exhaustive inclusion of studies | Limited, as information for a given brain region is present in few or no studies | Probable, as far as the included studies investigate the whole brain and not only some ROIs (in which case should be discarded) | More probable, because statistical parametric maps can also be included | ||
   Unbiased inclusion of studies | Limited, as information is only available for regions hypothesized a priori, ignoring the rest of the brain | Probable, as far as the included studies do not use different statistical thresholds for different parts of the brain (this is a strict inclusion criterion in SDM and ES-SDM) | |||
Statistical analyses | Â | Â | Â | Â | Â |
   Weighting of the studies | Complete (sample size and study precision) | None | Partial (only sample size) | Complete (sample size and study precision) | |
   Control of the heterogeneity | Residual heterogeneity is correctly included in the analyses | Residual heterogeneity is not controlled, and increases and decreases are not counteracted, potentially leading to voxels being detected as increased and decreased at the same time | Residual heterogeneity is not included in the weightings, but increases and decreases are counteracted | Residual heterogeneity is correctly included in the weightings | |
   Study of the heterogeneity | Possible, by means of meta-regressions and subgroup analyses | Limited to subgroup analyses | Possible, by means of meta-regressions and subgroup analyses | ||
   Correction for multiple comparisons | Possible | Not possible, questionable or limited to conventional voxel-thresholded cluster-based methods | |||
   Description of the effect sizes | Possible | Not possible | Possible though limited to pseudo-effect sizes based on the proportion of studies reporting significant findings | Possible | |
   Description of relevant non-significant trends | Possible, as the number of ROIs is manageable | Not possible, or limited to the visual inspection of liberally thresholded maps, as the number of voxels is too massive for a more accurate individual inspection |