Table 3: SLS participant characteristics. Year of testing Measure Baseline Year 7 Year 14 Year 21 (
𝑛
=
1
6
4
9
) (
𝑛
=
9
3
9
) (
𝑛
=
4
4
5
) (
𝑛
=
1
7
8
) Retention from previous testing (%) 56.4 47.7 40.8 Age [M (SD)] 67.1 (8.2) 72.9 (7.3) 77.9 (6.4) 81.8 (4.9) Education [M (SD)] 14.6 (2.9) 14.7 (2.8) 14.8 (2.7) 14.8 (2.8) Sex, female [
𝑛
(%)] 859 (52) 502 (54) 255 (57) 108 (60) Reasoning [M (SD)] 15.6 (5.8) 15.2 (5.6) 14.3 (5.5) 14.0 (5.3) Fluency [M (SD)] 38.6 (12.8) 37.5 (13.1) 36.7 (12.7) 38.8 (14.5) Memory [M (SD)] 12.5 (4.0) 12.0 (4.1) 11.5 (4.2) 11.6 (4.0) Semantic knowledge [M (SD)] 25.0 (6.7) 25.3 (6.6) 25.8 (6.2) 25.8 (5.9) Cognitive activity [M (SD)] 2.4 (1.2) 2.5 (1.2) 2.5 (1.2) 2.3 (1.2) Activity change [M (SD)] — −0.1 (1.1) −0.2 (1.1) −0.5 (1.3)
M: mean; SD: standard deviation. The theoretical ranges for each measure with a defined upper limit are as follows: education = 0–20, reasoning = 0–30, memory = 0–20, semantic knowledge = 0–36, and cognitive activity = 0–5.