Correction: Quantitative Amyloid Imaging in Autosomal Dominant Alzheimer’s Disease: Results from the DIAN Study Group

There are errors in the published article. Incorrect sample sizes were reported in Table 4 and Table 6. The intended sample size calculation was based on two-sided two-sample t-test to estimate the number of participants per arm needed to detect the specified reduction in amyloid accumulation rate due to treatment with 80% power and two-tailed type-I error of p = 0.05 in a 12-month placebo-controlled randomized clinical trial. The tables with corrected sample size values can be seen here.

Table 4. Longitudinal SUVR analysis for mean cortical regions in mutation carriers.

	MC_CER	MC_BS	MC_CW	MC_TW	MCRSF_CER	MCRSF_BS	MCRSF_CW	MCRSF_TW
Baseline	1.73±0.58	1.15±0.35	1.08±0.31	0.99±0.14	2.54±1.28	1.43±0.63	1.53±0.73	1.43±0.56
follow-up	1.76±0.60	1.17±0.35	1.12±0.32	1.00±0.14	2.65±1.36	1.48±0.64	1.64±0.80	1.49±0.57
delta	0.03±0.11	0.01±0.07	0.04±0.07	0.01±0.03	0.11±0.26	0.05±0.10	0.11±0.17	0.06±0.11
delta%	1.63±7.04	1.51±6.30†	3.34±5.88	1.29±3.54	4.19±11.07*‡	4.08±9.86*‡	7.03±11.27*	5.05±9.82*
p (follow-up vs. Baseline)	7.22E-02	1.39E-01	1.70E-05	8.12E-03	8.78E-04	6.25E-04	7.46E-06	1.14E-04
Rate	0.01±0.08	0.00±0.04	0.02±0.04	0.01±0.02	0.07±0.18	0.02±0.06	0.07±0.13	0.04±0.07
Effect Size	0.15	0.07	0.55	0.38	0.38	0.38	0.51	0.50
sample size (25% reduction in Rate)	11425	48016	819	1744	1712	1701	956	1001
sample size (50% reduction in rate)	2857	12005	206	437	429	426	240	251

MC_CER = mean cortical region SUVR using cerebellar cortex as reference; MC_BS = mean cortical region SUVR using brainstem as reference; MC_CW = mean cortical region SUVR using core white matter as reference; MC_TW = mean cortical region SUVR using total white matter as reference; MCRSF_CER = mean cortical region SUVR using cerebellar cortex as reference with RSF partial volume correction; MCRSF_BS = mean cortical region SUVR using brainstem as reference with RSF partial volume correction; MCRSF_CW = mean cortical region SUVR using core white matter as reference with RSF partial volume correction; MCRSF_TW = mean cortical region SUVR using total white matter as reference with RSF partial volume correction; delta = change in SUVR from baseline to follow-up; delta% = percent change in SUVR from baseline to follow-up; p is the strength of the difference between follow-up and baseline SUVRs based on a paired t-test; Rate = the annual rate of SUVR change; sample size is the estimated number of participants per arm needed to detect a 25% or a 50% reduction in amyloid accumulation rate due to treatment with 80% power and a two-tailed type-I error of p = 0.05 in a 12-month placebo-controlled randomized clinical trial.

*percent change in MCSUVR significantly greater with PVC than without (p<0.0005)

†percent change in MCSUVR significantly smaller than CW referencing (p<0.01)

‡percent change in MCSUVR with PVC significantly smaller than CW referencing (p<0.05)

Table 6. Mean cortical measurement for longitudinal cohort participants with full dynamic PiB.

	MC_CER	MC_BS	MC_CW	MC_TW	MCRSF_CER	MCRRSF_BS	MCRRSF_CW	MCRRSF_TW	MCBP	MCBPRSF
Baseline	1.83±0.59	1.18±0.35	1.12±0.31	1.02±0.16	2.80±1.33	1.50±0.64	1.60±0.71	1.54±0.62	0.62±0.45	1.33±0.93
follow-up	1.89±0.58	1.22±0.35	1.16±0.32	1.03±0.15	2.93±1.33	1.58±0.66	1.71±0.75	1.60±0.62	0.67±0.45	1.43±0.95
delta	0.05±0.13	0.04±0.06	0.04±0.05	0.01±0.04	0.14±0.29	0.09±0.09	0.11±0.12	0.06±0.11	0.05±0.10	0.10±0.22
p (follow-up vs. Baseline)	6.34E-02	1.98E-03	4.47E-04	8.39E-02	3.33E-02	2.02E-04	1.68E-04	1.19E-02	2.91E-02	3.84E-02
Rate	0.02±0.09	0.02±0.03	0.02±0.03	0.00±0.02	0.05±0.17	0.04±0.05	0.05±0.06	0.03±0.05	0.02±0.05	0.04±0.11
Effect Size	0.23	0.62	0.71	0.25	0.33	0.85	0.82	0.49	0.33	0.34
sample size (25% reduction in Rate)	4570	662	499	4072	2339	350	373	1034	2350	2192
sample size (50% reduction in rate)	1143	167	126	1019	586	89	94	260	589	549

MC_CER = mean cortical region SUVR using cerebellar cortex as reference; MC_BS = mean cortical region SUVR using brainstem as reference; MC_CW = mean cortical region SUVR using core white matter as reference; MC_TW = mean cortical region SUVR using total white matter as reference; MCRSF_CER = mean cortical region SUVR using cerebellar cortex as reference with RSF partial volume correction; MCRSF_BS = mean cortical region SUVR using brainstem as reference with RSF partial volume correction; MCRSF_CW = mean cortical region SUVR using core white matter as reference with RSF partial volume correction; MCRSF_TW = mean cortical region SUVR using total white matter as reference with RSF partial volume correction; MCBP = mean cortical binding potential; MCBPRSF = mean cortical binding potential with RSF partial volume correction; delta = change in SUVR from baseline to follow-up; p is the strength of the difference between follow-up and baseline SUVRs based on a paired t-test; Rate = the annual rate of SUVR change; sample size is the estimated number of participants per arm needed to detect a 25% or a 50% reduction in amyloid accumulation rate due to treatment with 80% power and a two-tailed type-I error of p = 0.05 in a 12-month placebo-controlled randomized clinical trial.