Table 1.
Demographic Characteristics and Scan Parameters by Diagnostic Group
| Parameter | Controls (n=21) | SPD Participants (n=18) | pa |
|---|---|---|---|
| Demographic (Mean ± SD unless otherwise noted) | |||
| Age | 40.76 ± 5.80 | 42.30 ± 7.42 | 0.473 |
| Sex (% male) | 67% | 67% | 1.00 |
| Ethnicity (%) | 38% C, 48% AA, 14% H | 39% C, 22% AA, 39% H | 0.959b |
| Smoking status (% yes) | 29% | 29%c | 0.955 |
| Parental education (years) | 14.65 ± 3.22d | 13.40 ± 4.07d | 0.317 |
| Participant education (years) | 15.20 ± 2.09e | 14.33 ± 2.91 | 0.295 |
| Scan parameters (Mean ± SD) | |||
| Injected dose (mCi) | 13.24 ± 3.70 | 11.01 ± 2.93 | 0.046 |
| Injected mass (ug) | 4.91 ± 1.08 | 4.32 ± 1.48 | 0.166 |
| Specific activity (Ci/mmol) | 921.86 ± 285.72 | 985.00 ± 553.65 | 0.650 |
| Plasma free fraction (fp, %) | 0.89 ± 0.26f | 0.73 ± 0.15 | 0.024 |
| VND (mL/cm3) | 2.25 ± 0.48 | 2.17 ± 0.46 | 0.614 |
AA=African American; C=Caucasian; H=Hispanic; SD=standard deviation; SPD=schizotypal personality disorder; VND=nondisplaceable distribution volume (measured in the cerebellum to provide a measure of non-specific radioligand binding).
a
For continuous variables, independent-samples t-test; for dichotomous variables, chi-square tests used.
b
Groups were compared on a dichotomized ethnicity variable (Caucasian v. ethnic minority).
c
Smoking status was missing for 1 SPD participant.
d
Parental education was missing for 3 SPD participants and 1 control.
e
Participant education was missing for 1 control.
f
Plasma free fraction was missing for 1 control.