Table 3.
Comparison of A-Prime Values on a Spatial Working Memory Task with Community Normal Controls
| A-Prime Deviation from Community Normal Mean |
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| Above 1 SD |
Within 1 SD |
Below 1–2 SD |
Below 2 SD |
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| Group (N) | Mean (SD) | N | % | N | % | N | % | N | % | RR | χ2 (1 df) | P-Value |
| Community Normal (36) | 0.82 (0.06) | 6 | 17 | 25 | 69 | 3 | 8 | 2 | 6 | 1.00 | ||
| Family Normal (23) | 0.81 (0.09) | 4 | 17 | 13 | 57 | 3 | 13 | 3 | 13 | 1.88 | 1.38 | 0.24 |
| Community Spectrum (14) | 0.78 (0.14) | 1 | 7 | 8 | 79 | 0 | 0 | 2 | 14 | 1.03 | > 0.01 | 0.97 |
| Family Spectrum (17) | 0.76 (0.14) | 2 | 12 | 8 | 47 | 4 | 24 | 3 | 18 | 2.97 | 4.91 | 0.027 |
| Schizophrenia Patients (23) | 0.72 (0.13) | 1 | 4 | 10 | 43 | 4 | 17 | 8 | 35 | 3.76 | 10.03 | 0.002 |
Note: RR = relative risk (compared to community normal) of impaired SWM score (> 1 SD below normal mean). In pairwise comparisons of the percentage with impaired SWM scores among other groups, community spectrum participants had significantly fewer than schizophrenia patients (χ2 = 5.31, p = .021), and family normal participants had marginally fewer than patients with schizophrenia (χ2 = 3.29, p = .070). Comparisons of percentage with impaired SWM between family spectrum versus community spectrum (p = .10), family normal versus community spectrum participants (p = .40), and family normal versus family spectrum participants (p = .31) were not statistically significant.