Table 2.

Power calculations for a multicenter trial estimating the association between percent change in FDG PET SUV and pathologic response to neoadjuvant chemotherapy for patients with locally advanced breast cancer, calculated by simulation of 10,000 datasets with characteristics described in Table 1.

Error conditions for each scenario:	1	2	3	4	5	6	7
	Ref. power	20%/40%	20%/40%	−20%/−40%	0.25/0.50	0.25/0.50	−0.25/−0.50
Simulation scenarios:		pct error	pct bias	pct bias	abs error	abs bias	abs bias
75% from primary sites
- all data analyzed (no selection by SUV0)	0.92	0.71	0.78	0.60	0.78	0.78	0.79
- enriched sample (observed SUV0 ≥ 3)	0.87	0.70	0.79	0.54	0.73	0.76	0.70
25% from primary sites
- all data analyzed (no selection by SUV0)	0.92	0.54	0.69	0.36	0.67	0.66	0.68
- enriched sample (observed SUV0 ≥ 3)	0.87	0.57	0.71	0.32	0.62	0.65	0.57

SUV0 is SUV of first scan

N=100 for unselected design (200 scans), N < 100 for enrichment design (200 scans)