Table 2. Comparisons Between Groups: Baseline, Week 8, and Change in Hippocampal Volumetric Integrity.
| Characteristic | Total No. | Participants With FEP, Median (IQR) | Total No. | Healthy Controls, Median (IQR) | Test Statistic | P Value | Effect Size (r)a |
|---|---|---|---|---|---|---|---|
| Baseline LHVI | 57 | 0.9275 (0.8256 to 0.9689) | 54 | 0.9512 (0.8501 to 0.9825) | 841.00 | .001 | .391 |
| Baseline RHVI | 57 | 0.9237 (0.8525 to 0.9661) | 54 | 0.9412 (0.8681 to 0.9690) | 967.00 | .001 | .320 |
| Baseline LHVI (completers) | 24 | 0.9323 (0.8343 to 0.9789) | 31 | 0.9633 (0.9138 to 0.9876) | 157.00 | .001 | .481 |
| Baseline RHVI (completers) | 24 | 0.9277 (0.8623 to 0.9678) | 31 | 0.9537 (0.8795 to 0.9722) | 445.00 | .001 | .476 |
| Week 8 LHVI | 24 | 0.9297 (0.8083 to 0.9763) | 32 | 0.9636 (0.9149 to 0.9908) | 111.00 | .001 | .654 |
| Week 8 RHVI | 24 | 0.9239 (0.8575 to 0.9597) | 32 | 0.9548 (0.8795 to 0.9722) | 88.50 | .001 | .604 |
| Median annualized change in LHVI | 24 | −0.03791 (−0.0758 to 0.0049) | 31 | 0.001151 (−0.0165 to 0.0207) | 179.00 | .001 | .441 |
| Median annualized change in RHVI | 24 | −0.03027 (−0.0817 to 0.00004) | 31 | 0.004535 (−0.0151 to 0.0350) | 184.00 | .001 | .430 |
Abbreviations: FEP, first episode of psychosis; LHVI, left hippocampal volumetric integrity; RHVI, right hippocampal volumetric integrity.
a
Effect sizes were calculated using the z score statistic from each Mann-Whitney test comparison of median values, divided by the square root of the sample size.