780 vII. APPLICATIONS  AND  IMPLICATIONS
and a conscientious trajectory (Caspi, Hari -
ri, Holmes, Uher, & Moffitt, 2010), and 
they often involve social relations and com -
munity. It is not the case, however, that SES 
accounts for conscientiousness effects (e.g., 
Pluess & Bartley, 2015). Furthermore, the 
absolute level may be important. Only very 
low or very high levels of conscientiousness 
may be dangerous or protective.
Weiss and Costa (2005) evaluated ele -
ments of the five-  factor personality model 
as predictors of mortality in a community 
sample of men and women ages 65–100. 
They confirmed protective effects of high 
conscientiousness on mortality over a 5-year 
follow-  up. Longer-  term follow-  up then con -
firmed self-  discipline as a powerful predic -
tor of survival (Costa, Weiss, Duberstein, 
Friedman, & Siegler, 2014). Wilson, Mendes 
de Leon, Bienias, Evans, and Bennett (2004) 
studied personality predictors of mortality 
in a group of elderly Catholic clergy mem -
bers (men and women, no dementia at base -
line) followed for 5 years. The risk of mor -
tality was halved for those with high versus 
low conscientiousness scores, when the ef -
fects of the other traits and physical health 
were controlled.
These results are all the more striking 
when viewed from a lifespan perspective, be -
cause less conscientious individuals are more 
likely to die at all ages (Friedman & Kern, 
2014; Friedman, Tucker, Schwartz, Martin, 
et al., 1995; Martin et al., 2007); hence, the 
survivors into old age are likely to be rela -
tively conscientious! That is, when studying 
the relation between personality and health 
in older samples, an important caveat is the 
issue of the “survival elite”—these are indi -
viduals who have survived the other predic -
tors of mortality (Korten et al., 1999). The 
relations can be weaker (or different) in 
old age, in part because of selective earlier 
mortality or successful treatment (Swan & 
Carmelli, 1996). Moreover, simple health– 
behavior or physiological models are less 
applicable in old age when insults have ac -
cumulated, physical limitations place restric -
tions on activities, and body chemistry has 
changed. Other issues for research with older 
samples include the distinction between nor -
mal aging and terminal decline preceding 
death; the presence of illness and disability; 
social disruptions; and stronger influence of 
genetic factors in extreme old age.Negative Emotionality/Neuroticism 
(Emotional  Instability)
The discovery of replicable associations be -
tween child and young adult traits and life -
long mortality risk has been a major devel -
opment in health psychology in the past 25 
years, and has contributed to the revitaliza -
tion of the study of individual differences as 
predictors of consequential outcomes (Ozer 
& Benet-Martínez, 2006). Not only traits 
associated with more rational processes— 
especially conscientiousness—  but also  traits 
associated with affective processes—espe -
cially negative emotionality—  are important 
influences on later adult morbidity and mor -
tality.
In the study of Cardiovascular Risk in 
Young Finns (CRYF), a representative co -
hort study, negative emotionality and hy -
peractivity (restlessness and impatience) in 
both boys and girls ages 9–15, assessed by 
mothers’ ratings, predicted adverse changes 
on indicators of the metabolic syndrome 3 
years later (Ravaja & Keltikangas-  Järvinen, 
1995). Expanding on this study, Pulkki- 
Råback, Elovainio, Kivimäki, Raitakari, 
and Keltikangas-  Järvinen (2005) examined 
the younger CRYF cohorts. They related 
maternal ratings of temperament (negative 
emotionality and aggression, activity, and 
sociability) at ages 6–12 to BMI assessed in 
young adulthood (ages 24–30), finding that 
negative emotionality had the strongest as -
sociation with adult BMI, after controlling 
for childhood BMI and several other well- 
established risk factors, such as parents’ 
obesity. Consistent with transactional and 
interactional models, these children may 
evoke more stress in their lives and be more 
responsive to stress. Consistent with psycho -
physiological models, psychosocial stress in 
childhood is associated with weight gain in 
adulthood (e.g., Williamson, Thompson, 
Anda, Dietz, & Felitti, 2002). Support for 
a psychosocial stress model of negative emo -
tionality and obesity also comes from the 
Dunedin study, which found a link between 
lower childhood SES and higher BMI at age 
26, independent of adult SES (Poulton et al., 
2002).
Many studies have shown a prospective 
association between aspects of difficult 
temperament (e.g., hostility) in childhood 
and subsequent unhealthy behavior, includ -