Table 1.
Description of the studies included in our meta-analysis.
| ARTICLE | Risks of BIAS | APPLICABILITY Concerns | Paradigm | Modality | Responders |
|---|---|---|---|---|---|
| Bekinschtein (2009) [17] | HIGH | LOW | Local-global effect (count) | fMRI/EEG | 28.57% |
| Chennu (2013) [18] | HIGH | LOW | Local-global effect (count) | fMRI/EEG | 19.05% |
| Chennu (2014) [19] | HIGH | LOW | Local-global effect (count) | EEG | 43.33% |
| Cruse (2011) [20] | LOW | LOW | Motor imagery | EEG | 20.00% |
| Cruse (2012) [21] | HIGH | LOW | Motor imagery | EEG | 21.05% |
| Edlow (2017) [22] | LOW | HIGH | Motor imagery | fMRI/EEG | 43.75% |
| Faugeras (2011) [23] | HIGH | LOW | Count target | EEG | 9.09% |
| Gibson (2014) [24] | HIGH | LOW | Spatial and motor imagery | fMRI/EEG | 66.67% |
| Habbal (2014) [25] | LOW | LOW | Motor imagery | EMG | 10.53% |
| Hauger (2015) [26] | HIGH | LOW | Count target | EEG | 10.00% |
| Hauger (2017) [27] | HIGH | LOW | Count target | EEG | 62.50% |
| Holler (2013) [28] | HIGH | LOW | Motor imagery | EEG | 35.71% |
| King (2013) [29] | HIGH | LOW | Count target | EEG | 26.14% |
| Li (2015) [30] | HIGH | LOW | Mental calculation | EEG | 33.33% |
| Monti (2010) [9] | HIGH | LOW | Spatial and motor imagery | fMRI | 7.69% |
| Schnakers (2015) [31] | LOW | LOW | Focus attention | EEG | 19.05% |
| Schnakers (2008) [32] | LOW | LOW | Count target | EEG | 27.27% |
| Stender (2014) [33] | HIGH | LOW | Spatial and motor imagery | fMRI | 33.33% |
| Vogel (2013) [34] | HIGH | LOW | Spatial and motor imagery | fMRI | 60.00% |
| Wang (2015) [35] | HIGH | LOW | Count target | EEG | 71.43% |
| Yu (2013) [36] | HIGH | LOW | Count target | fMRI | 11.63% |
| Chatelle (2018) [37] | LOW | HIGH | Count and motor imagery | EEG | 40.00% |
| Curley (2018) [38] | LOW | LOW | Motor imagery | fMRI/EEG | 34.78% |
| Spataro (2018) [39] | HIGH | LOW | Count target | EEG | 30.77% |
| Xie (2018) [40] | HIGH | LOW | Focus attention | EEG | 37.50% |
This table reports the risk of bias and applicability concerns based on the QUADAS-2. The paradigm and modality used to detect covert cognition in each study are also described (fMRI = functional magnetic resonance imaging, EEG = electroencephalography, and EMG = electromyogram).