Comparison of fMRI scan quality between groups without a prescan interview and those with a prescan interview
| Variable | No Prescan Interview | With Prescan Interview | P Value | ||
|---|---|---|---|---|---|
| Patients (n = 96) | Scans (n = 460) | Patients (n = 106) | Scans (n = 539) | ||
| Unacceptable sequences | – | 15.2% (70/460) | – | 10.9% (59/539) | .04 |
| Unacceptable studies | 9.4% (9/96) | – | 1.9% (2/106) | – | .02 |
| Fraction of outlying data points during time course | – | 0.65% | – | 0.59% | .004 |
| SD of linear displacements of image centroid (range, voxels) | – | 0.008 | – | 0.007 | <.01 |
| 0.022 | 0.019 | <.01 | |||
| 0.012 | 0.010 | <.01 | |||
| SD of angular displacements of image centroid (range) | – | 0.17° | – | 0.10° | <.001 |
| 0.19° | 0.12° | <.001 | |||
| 0.21° | 0.10° | <.001 | |||
Note:—This analysis was conducted grouping the data on the scan/sequence basis and the patient basis. The extra numbers seen on the scan-basis analysis could not be meaningfully extended into the patient basis and therefore hyphens are used.