Social Activity and Cognitive Functioning Over Time: A Coordinated Analysis of Four Longitudinal Studies

Table 3

SLS participant characteristics.

	Year of testing
Measure	Baseline (𝑛=1657)	Year 7 (𝑛=940)	Year 14 (𝑛=446)	Year 21 (𝑛=181)
	M (SD)	M (SD)	M (SD)	M (SD)
Retention from previous testing (%)		57	47	41
Age	67.1 (8.2)	73.0 (7.23)	78.0 (6.4)	81.9 (4.9)
Education	14.6 (2.9)	14.7 (2.8)	14.8 (2.7)	14.8 (2.8)
Sex, female [𝑛 (%)]	861 (52)	507 (54)	256 (57)	108 (60)
Reasoning	15.6 (5.8)	15.2 (5.6)	14.3 (5.5)	14.0 (5.25)
Fluency	38.5 (12.8)	37.5 (13.1)	36.7 (12.7)	38.8 (14.5)
Memory	12.5 (4.0)	12.0 (4.1)	11.5 (4.1)	11.6 (4.0)
Semantic knowledge	25.0 (6.7)	25.3 (6.6)	25.8 (6.2)	25.9 (5.9)
Social activity	3.5 (1.6)	3.5 (1.6)	3.5 (1.6)	3.3 (1.6)
Social activity change	—	−0.1 (1.5)	−0.2 (1.6)	−0.4 (1.7)

M: mean, SD: standard deviation. The range for each measure with a defined upper limit is as follows: education = 0–20, reasoning = 0–30, memory =0-20, semantic knowledge = 0–36, and social activity = 0–7.