Table 2 Baseline characteristics of the recruited subjects in the individual studies

Doganavsargil Baysal, G.O. (2013)

yes

lithium: 11 patients (18.33%) valproic acid:6 patients (10%) mood stabilizing drugs plus antipsychotic drugs:30 patients (50%) two mood stabilizing drugs: 12 patients (20%)

Subjects who had not been diagnosed with a psychiatric disease and did not have a known significant medical condition or mental development disorder

n/a

n/a

n/a

Turkey

Ezzaher, A. (2011)

yes

Valproic acid: 46 patients (50%) Lithium: 10 patients (10.9%) Carbamazepine: 9 patients (9.8%) Valproic acid and lithium: 3 patients (3.2%) Antipsychotics: 24 patients (26.1%)

None of the controls had psychiatric illnesses, epilepsy, mental retardation, hormone therapy, history of vitamin use, diabetes, cardiovascular disease, thyroid dysfunction, liver disease or renal dysfunction.

n/a

n/a

C677T MTHFR polymorphism was studied but no significant finding

Tunisia

Diass, V.V. (2009)

yes

n/a

Healthy individuals were screened for personal and first-degree family axis I psychiatric disorders with the MINI.

n/a

n/a

n/a

Spain

Ozbek, Z. (2008)

yes

Atypical antipsychotic: 17% typical antipsychotic: 65% atypical antipsychotic in combination with typical antipsychotic: 18%

Healthy and unrelated volunteers without psychiatric disorders were selected as a control group.

n/a

n/a

Patients carrying TT and/or AA and AC genotypes in methylenetetrahydrofolate (MTHFR) gene variants of c.1298A > C (Glu429Ala) and c.677C > T (Ala222Val) reduced folate levels

Turkey

Lerner, V. (2006)

yes

n/a

Subjects from community clinics with no record of psychiatric illness

n/a

n/a

n/a

Israel

Hasanah, C.I. (1997)

inpatient, n/a

n/a

The control group was taken from the out-patient clinic. Only patients with minor ailments like headaches, cough and cold were taken.

Exclusion criteria for the control group were, family history and past history of psychiatric illness, substance misuse, recent weight loss, sleep disturbance, pregnancy and puerperium.

n/a

n/a

n/a

Malaysia