Table 2.
Motion characteristics of young and elderly participantsa
| Characteristic | Young adults | Elderly |
||
|---|---|---|---|---|
| Baseline | Second time point | Third time point | ||
| Prescrubbing | ||||
| Relative motion (mm) | 0.050 (0.024) | 0.071 (0.028) | 0.072 (0.029) | 0.067 (0.028) |
| Absolute motion (mm) | 0.261 (0.193) | 0.247 (0.146) | 0.264 (0.153) | 0.279 (0.219) |
| Postscrubbing | ||||
| Relative motion (mm) | 0.045 (0.016)* | 0.063 (0.021) | 0.064 (0.022) | 0.062 (0.020) |
| Absolute motion (mm) | 0.238 (0.164) | 0.232 (0.117) | 0.244 (0.140) | 0.254 (0.195) |
| Number of volumes | 220.8 (23.3)* | 211.0 (25.2) | 212.8 (24.7) | 220.1 (19.9) |
aData are mean (SD).
*Postscrubbing motion parameters that showed significant differences (p < 0.05) between young and elderly participants. Within the healthy elderly, no postscrubbing motion parameters showed significant changes with time.