Table 1.

Means and Standard Deviations for All Variables Examined

Variable	M	SD
Primary variables
Adult health quality (ages 25–27)	14.7	3.42
Close-friendship quality (age 13)	.01	.55
Allocentrism vis-à-vis peers (ages 14–17)	.01	.27
Internalizing symptoms (ages 25–27)	.00	.82
Body mass index (ages 25–27)	26.8	7.9
History of serious illness prior to age 18	.18	.46
Family income (age 13)	6.1	2.0
Additional potential confounds
Depressive symptoms (ages 13–15)	5.8	4.6
Anxiety (ages 13–15)	6.6	8.0
Physical attractiveness (ages 13–15)	3.7	0.7
Hard-drug use (ages 14–15)	1.04	0.27
Hard-drug use (ages 25–27)	0.54	2.04
Extraversion (age 23)	35.0	7.5
Agreeableness (age 23)	39.8	5.5
Conscientiousness (age 23)	37.4	6.1
Emotional stability (age 23)	34.2	8.7
Imagination (age 23)	38.8	5.7

Note: For variables assessed across a range of years, items were assessed annually, and the scores were averaged.