TABLE 1. Sociodemographic Characteristics of Probands With Schizophrenia, Schizoaffective Disorder, or Psychotic Bipolar I Disorder, Their Relatives, and Healthy Comparison Subjectsa.
| Variable | Probands |
Relatives |
Healthy Comparison Subjects (N=459) | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Schizophrenia (N=397) | Schizoaffective Disorder (N=224) | Bipolar Disorder (N=312) | Schizophrenia (N=415) | Schizoaffective Disorder (N=280) | Bipolar Disorder (N=360) | |||||||||
| Mean | SD | Mean | SD | Mean | SD | Mean | SD | Mean | SD | Mean | SD | Mean | SD | |
| Age (years)b | 35.7 | 12.7 | 36.6 | 11.9 | 36.4 | 12.9 | 43.3 | 15.0 | 40.1 | 16.0 | 40.0 | 15.9 | 36.5 | 12.7 |
| Education (years)c | 12.7 | 2.3 | 13.1 | 2.2 | 14.1 | 2.4 | 13.9 | 2.4 | 13.6 | 2.9 | 14.4 | 2.8 | 14.8 | 2.5 |
| N | % | N | % | N | % | N | % | N | % | N | % | N | % | |
| Male genderd | 267 | 67.3 | 93 | 41.5 | 110 | 35.4 | 132 | 31.8 | 83 | 30.0 | 130 | 36.5 | 210 | 46.0 |
| Hispanic ethnicity | 32 | 8.1 | 21 | 9.4 | 24 | 7.7 | 34 | 8.2 | 25 | 9.0 | 26 | 7.3 | 39 | 8.5 |
| Racee | ||||||||||||||
| Caucasian | 182 | 45.8 | 121 | 54.0 | 227 | 72.8 | 219 | 52.8 | 161 | 57.5 | 278 | 77.2 | 283 | 61.7 |
| African American | 181 | 45.6 | 90 | 40.2 | 67 | 21.5 | 173 | 41.7 | 102 | 36.4 | 62 | 17.2 | 132 | 28.8 |
| Other | 34 | 8.6 | 13 | 5.8 | 18 | 5.8 | 23 | 5.5 | 17 | 6.1 | 20 | 5.6 | 44 | 9.6 |
| Handedness | ||||||||||||||
| Right-handed | 309 | 85.1 | 193 | 86.5 | 251 | 84.2 | 353 | 88.9 | 236 | 87.1 | 303 | 86.1 | 379 | 88.3 |
| Left-handed | 46 | 12.7 | 22 | 9.9 | 42 | 14.1 | 39 | 9.8 | 29 | 10.7 | 45 | 12.8 | 44 | 10.3 |
| Ambidextrous | 8 | 2.2 | 8 | 3.6 | 5 | 1.7 | 5 | 1.3 | 6 | 2.2 | 4 | 1.1 | 6 | 1.4 |
| Marital statusf | ||||||||||||||
| Married | 28 | 7.6 | 25 | 11.2 | 50 | 16.7 | 145 | 36.5 | 99 | 36.8 | 142 | 40.6 | 114 | 26.0 |
| Widowed | 4 | 1.1 | 1 | 0.4 | 8 | 2.7 | 16 | 4.0 | 10 | 3.7 | 7 | 2.0 | 8 | 1.8 |
| Divorced/separated | 45 | 12.3 | 61 | 27.4 | 74 | 24.7 | 77 | 19.4 | 41 | 15.2 | 47 | 13.4 | 64 | 14.6 |
| Never married | 290 | 79.0 | 136 | 61.0 | 167 | 55.9 | 159 | 40.1 | 119 | 44.2 | 154 | 44.0 | 252 | 57.5 |
| Hollingshead | ||||||||||||||
| Index of Social Position Participantg | ||||||||||||||
| Class 1 | 1 | 0.3 | 3 | 1.5 | 7 | 2.5 | 15 | 4.1 | 18 | 7.1 | 32 | 9.9 | 23 | 5.5 |
| Class 2 | 29 | 8.7 | 21 | 10.3 | 60 | 21.1 | 98 | 26.6 | 62 | 24.5 | 93 | 28.7 | 136 | 32.8 |
| Class 3 | 79 | 23.8 | 69 | 34.0 | 108 | 37.9 | 130 | 35.3 | 73 | 28.9 | 111 | 34.3 | 169 | 40.7 |
| Class 4 | 128 | 38.6 | 72 | 35.5 | 78 | 27.4 | 85 | 23.1 | 58 | 22.9 | 45 | 13.9 | 64 | 15.4 |
| Class 5 | 95 | 28.6 | 38 | 18.7 | 32 | 11.2 | 40 | 10.9 | 42 | 16.6 | 43 | 13.3 | 23 | 5.5 |
| Family of originh | ||||||||||||||
| Class 1 | 32 | 12.5 | 15 | 10.1 | 40 | 17.2 | 42 | 13.5 | 17 | 9.3 | 45 | 16.7 | 53 | 14.6 |
| Class 2 | 56 | 21.8 | 38 | 25.5 | 70 | 30.0 | 61 | 19.7 | 52 | 28.6 | 71 | 26.4 | 96 | 26.4 |
| Class 3 | 71 | 27.6 | 41 | 27.5 | 60 | 25.8 | 73 | 23.5 | 45 | 24.7 | 65 | 24.2 | 98 | 26.9 |
| Class 4 | 72 | 28.0 | 37 | 24.8 | 43 | 18.5 | 102 | 32.9 | 48 | 26.4 | 70 | 26.0 | 97 | 26.6 |
| Class 5 | 26 | 10.1 | 18 | 12.1 | 20 | 8.6 | 32 | 10.3 | 20 | 11.0 | 18 | 6.7 | 20 | 5.5 |
The largest numbers of subjects available for each study group are presented. Percentages for dichotomous variables were based on the number of subjects available for each group excluding missing data. Proportions of missing data ranged from 0.8% to 11.0% for various sociodemographic characteristics.
Significant overall difference (F=15.28, df=6, 2427, p<0.001). The relatives were older than the probands and comparison subjects. Tukey-Kramer post hoc test results (p<0.01): schizophrenia probands different from all three relative groups; probands with schizoaffective disorder different from schizophrenia relatives; bipolar probands different from schizophrenia relatives; schizophrenia relatives different from all three proband groups and comparison group; schizoaffective disorder relatives different from schizophrenia probands; bipolar disorder relatives different from schizophrenia probands and comparison group; comparison group different from schizophrenia and schizoaffective disorder relatives.
Significant overall difference (F=31.69, df=6, 2336, p<0.001). The comparison group had the highest education level, the bipolar probands had more education than the other proband groups, and relatives had more education than probands. Tukey-Kramer post hoc test results (p<0.01): schizophrenia probands different from bipolar probands, all three relative groups, and comparison group; schizoaffective disorder probands different from bipolar probands, schizoaffective and bipolar disorder relatives, and comparison group; bipolar probands different from other two proband groups and comparison group; schizophrenia relatives different from schizophrenia and schizoaffective disorder probands and comparison group; schizoaffective disorder relatives different from schizophrenia probands, bipolar disorder relatives, and comparison group; bipolar disorder relatives different from schizophrenia and schizoaffective disorder probands and from schizoaffective disorder relatives; comparison group different from schizophrenia, schizoaffective disorder, and bipolar disorder probands and from schizophrenia and schizoaffective disorder relatives.
Significant overall difference (χ2=151.01, df=6, p<0.001).
Significant overall difference (χ2=129.89, df=12, p<0.001).
Significant overall difference (χ2=253.79, df=18, p<0.001).
Significant overall difference (χ2=278.74, df=24, p<0.001).
Nonsignificant overall difference (χ2=39.09, df=24, p=0.03).