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Sample size needed to detect effect sizes of 15%, 20% and 25% in OEF, CBF and CMRO2 for three different study designs (significance level = 5%, statistical power = 80%).
| OEF |
CBF |
CMRO2 |
|||||||
|---|---|---|---|---|---|---|---|---|---|
| 15% | 20% | 25% | 15% | 20% | 25% | 15% | 20% | 25% | |
| (i) within subjects, within session | 14 | 8 | 5 | 15 | 9 | 6 | 24 | 14 | 9 |
| (ii) within subjects, between sessions | 8 | 4 | 3 | 11 | 6 | 4 | 12 | 7 | 5 |
| (iii) between subjects | 20 | 11 | 7 | 28 | 16 | 10 | 40 | 23 | 15 |
