Social Activity and Cognitive Functioning Over Time: A Coordinated Analysis of Four Longitudinal Studies
Table 4
VLS participant characteristics.
Year of testing
Measure
Baseline ()
Year 3 ()
Year 6 ()
Year 9 ()
Year 12 ()
Year 15 ()
Year 18 ()
M (SD)
M (SD)
M (SD)
M (SD)
M (SD)
M (SD)
M (SD)
Retention from previous testing (%)a
—
74
79
72
67
79
57
Age
68.6 (6.7)
71.3 (6.6)
73.7 (6.4)
76.5 (5.9)
79.3 (5.2)
82.2 (4.6)
85.1 (3.6)
Years of education at baseline
14.9 (3.3)
15.4 (3.2)
15.6 (3.1)
15.9 (3.1)
15.8 (3.1)
15.2 (3.1)
14.8 (2.8)
Sex, female [ (%)]
614 (62.8)
450 (62.2)
346 (60.6)
251 (61.1)
170 (61.8)
60 (65.9)
35 (67.3)
Reasoningb
11.2 (4.7)
11.7 (4.2)
10.3 (4.7)
10.3 (4.6)
9.9 (4.6)
7.5 (4.7)
6.5 (4.2)
Fluency
17.7 (4.3)
17.9 (4.4)
17.7 (4.5)
17.2 (4.8)
16.3 (4.9)
14.7 (5.8)
13.8 (5.4)
Memoryc
13.7 (5.9)
14.7 (6.0)
14.7 (6.1)
14.9 (6.4)
11.7 (5.4)
13.0 (6.3)
—
Semantic knowledge
43.7 (7.4)
44.7 (6.2)
44.3 (6.0)
44.2 (5.8)
43.5 (5.7)
42.7 (7.1)
42.6 (6.6)
Social activity
23.0 (6.9)
23.2 (7.2)
22.8 (7.3)
22.5 (7.2)
21.2 (7.1)
22.8 (7.7)
21.1 (7.2)
Social activity change
—
−0.1 (5.4)
−0.3 (6.0)
−0.9 (6.4)
−2.5 (6.9)
−3.5 (7.5)
−5.3 (8.1)
M: mean, SD: standard deviation. The range for each measure with a defined upper limit is as follows: reasoning = 0–20, Memory = 0−30, and Semantic knowledge 0−54.
aThe 1986 cohort was followed for up to 18 years, the 1993 cohort for up to 12.
bThe reasoning measure was not given until year 6 for the 1986 cohort.
cThe memory measure was not given in year 18.