First author Year Country Ethnicity Study design Number Gender (M/F) Source of controls Age Evidence of FCD Diagnosis of epilepsy Methods NMDA receptors Quality assessment Case Control Case Control Nobuhiro Mikuni et al. 1999 USA Caucasian Case-control 3 3 2/1 2/1 Non-CD tissue 7-18 Pathology Symptoms and EEG ICC and immunoblot analysis NR1 and NR2B Middle-high Nobuhiro Mikuni et al. 1999 USA Caucasian Case-control 3 3 2/1 2/1 Non-CD tissue 6-18 Pathology Symptoms and EEG ICC and immunoblot analysis NR1 Middle-high Ying  Z et al. 1999 USA Caucasian Case-control 11 11 11 11 Non-CD tissue   Pathology Symptoms and EEG Immunoblot analysis NR1 and NR2B Middle-high Thomas L Babb et al. 2000 USA Caucasian Case-control 3 3 3 3 Non-CD tissue   Pathology Symptoms and EEG Immunoblot analysis NR1 Middle-high Iniad M Najm et al. 2000 USA Caucasian Case-control 5 5 1/4 1/4 Non-CD tissue 15-29 Pathology Symptoms and EEG ICC NR1 and NR2B Middle-high Zhong Ying et al. 2004 USA Caucasian Case-control 4 4 1/3 1/3 Non-CD tissue 3.5-17 Pathology Symptoms and EEG Immunoblot analysis NR2B Middle-high Gabriel Moddel et al. 2005 USA Caucasian Case-control 20 8 8/12 8 Non-CD tissue 0-4 Pathology Symptoms and EEG ICC and immunoblot analysis NR2B Middle-high Akira Hodozuka et al. 2006 Japan Asian Case-control 15 15 7/8 7/8 Non-CD tissue 0.6-8 Pathology Symptoms and EEG Immunohistochemical staining NR1 and NR2A/B Middle-high Lei Liu et al. 2008 China Asian Case-control 20 4 14/6 4 Non-CD tissue 1-17 Pathology Symptoms and EEG En Vision NR1 and NR2A/B Middle-high Jie Zheng et al. 2011 China Asian Case-control 20 10 12/8 10 Non-CD tissue 18-45 Pathology Symptoms and EEG ICC NR1 and NR2A/B Middle-high

Table 1: Characteristics of included studies in this meta-analysis.