. Author manuscript; available in PMC: 2015 Nov 1.

Published in final edited form as: Alzheimers Dement. 2014 Jul 14;10(6):735–742.e4. doi: 10.1016/j.jalz.2014.04.520

Table 2.

Parameters of fitted sigmoid curves.

Cognitive marker	Inflection point^*, mean (SD)	Slope at inflection point^†, mean (SD)
CVLT immediate recall	0.98 (0.05)	−0.65 (0.02)
CVLT short delayed free recall	0.67 (0.05)	−1.05 (0.04)
CVLT long delayed free recall	0.81 (0.05)	−1.13 (0.04)
BVRT error	1.75 (0.59)	1.03 (0.24)
BMS	3.32 (0.31)	1.31 (0.18)
MMSE	4.04 (0.24)	−0.82 (0.06)

Parameter summary statistics were calculated using the results on the 200 bootstrap samples. MMSE = Mini-Mental State Examination; BMS = Blessed Information Memory Concentration Score; CVLT = California Verbal Learning Test; BVRT = Benton Visual Retention Test.

Inflection point is in ADPS units.

^†

Equivalently, this is the maximum slope of the fitted sigmoid curves normalized to the [0,1] range, in units of normalized cognitive score per ADPS. Negative slopes indicate decline in cognitive score over time. To obtain the sigmoid curves in Figure 3, absolute values of the slopes were used.