Demographic and clinical characteristics of the study groups
| Characteristics | Patients with schizophrenia (n=100) | Healthy controls (n=100) | Statistics | P value |
| Sex (male/female) | 49/51 | 35/65 | χ2=11.562* | 0.073 |
| Age (years), mean (SD) | 42.38 (15.38) | 40.60 (14.9) | t=−0.703† | 0.482 |
| Marital status (married/single) | 33/67 | 58/42 | χ2=12.602* | <0.001 |
| Residence (urban/suburban) | 53/47 | 66/34 | χ2=3.506* | 0.061 |
| Permanent employment (yes/no) | 11/89 | 85/15 | χ2=109.695* | <0.001 |
| Family history of psychiatric disorders (n=77) | 65 (84.4%) | 12 (15.6%) | χ2=59.318* | <0.001 |
| Comorbidities (n=53) | 32 (60.4%) | 21 (39.6%) | χ2=3.106* | 0.109 |
| Regular psychiatric treatment of any kind (n=72) | 72 (100.0%) | 0 (0.0%) | χ2=109.397‡ | <0.001 |
| Smoking (n=99) | 63 (63.6%) | 36 (36.4%) | χ2=14.581* | <0.001 |
| Education level (university/high school or lower) | 8/92 | 67/33 | χ2=74.261* | <0.001 |
*χ2 value.
†t value.
‡Fisher’s exact test value.