Table 1.

Cognitive function tests used, ranges in their scores (possible and observed within the study), and cut-off points used to define cognitive impairment

Cognitive function test	Range possible		Range in study		Cut-off point
	Min	Max	Min	Max
Age-Related Eye Disease Study
3MS*	0	100	47	100	≤79
Buschke immediate recall	0	100	0	83.3	≤8.3
Buschke overall word list	0	12	0	11.2	≤3.3
Logical memory part I	0	75	0	69	≤22
Logical memory part II	0	50	0	45	≤9
Animal category	0	-	0	44	≤11
Letter fluency	0	-	1	91	≤21
Logical memory part I	0	75	0	69	≤22
Logical memory part II	0	50	0	45	≤9
Digits backwards†	0	12	0	12	≤3
Composite score‡	-	-	-23.5	17.9	≤−7.0
Age-Related Eye Disease Study 2
TICS-M*	0	41	12	41	≤29
TICS-M recall	0	10	0	10	=0
Animal category	0	-	0	43	≤10
Letter fluency	0	-	0	118	≤19
Alternating fluency	0	-	0	14	≤1
Logical memory part I	0	75	0	69	≤22
Logical memory part II	0	50	0	46	≤9
Digits backwards†	0	100	0	100	≤23
Composite score‡	-	-	-21.1	17.6	≤−7.0

TICS-M = Telephone Interview Cognitive Status-Modified; 3MS = Modified Mini-Mental State Examination

^*The 3MS has a pre-defined cut-off point for cognitive impairment of 80 and the TICS-M has one of 30. For the other tests, cognitive impairment is defined as being in the lowest decile, except for the TICS-M recall, for which it is defined as being in the lowest quintile. In both study cohorts, the cut-off points were determined using only the participants included in the analyses; in AREDS2, the cut-off points were determined using all time-points (though the same cut-off point is used for all study visits)

^†Different versions of the digits backwards test were used in AREDS and AREDS2, hence the difference in the score ranges

^‡Composite score is the sum of Z-scores from each test within the battery.