Table 3.
SLS participant characteristics.
| Year of testing | ||||
|---|---|---|---|---|
| Measure | Baseline | Year 7 | Year 14 | Year 21 |
| (n = 1649) | (n = 939) | (n = 445) | (n = 178) | |
| 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.