than for those initially aged 17–25. Differences in instrument are also
important. The MMPI scales studied by Gloria Leon and her colleagues(Leon, Gillum, Gillum, & Gouze, 1979) were intended to assess psy -
chopathology , not personality traits, and so are not fully appropriate for
a study of personality in a psychiatrically normal sample. Jack Block’s(1977) results, using a standard personality inventory in a large groupof men initially over age 30, are precisely in line with the findings in Ta -
ble 11.
The 6-year longitudinal study of the NEO-PI discussed in Chapter
4 (Costa & McCrae, 1988b) was also the basis for an analysis of the sta -The Course of Personality Development 111
TABLE 12. Stability Coefficients from Some Longitudinal Studies Using Self-Reports
Initial RetestCorrelations
Study Instrument N Sex age interval Range Median
J. Block (1977) CPI 219 M, F 31–38 10 .71
Siegler et al. (1979) 16PF 331 M, F 45–70 2 .50Leon et al. (1979) MMPI 71 M 45–54 13 .07–.82 .50
MMPI 71 M 58–67 17 .03–.76 .52MMPI 71 M 45–54 30 .28–.74 .40
Mortimer et al. (1982) Self-concept 368 M College 10 .51-.63 .55Conley (1985) KLS factors 378 M, F 18-35 20 .34–.57 .46A. Howard & D. Bray
aEPPS 266 M Adult 20 .31–.54 .42
GAMIN 264 M Adult 20 .45–.61 .57
Stevens & Truss (1985) EPPS 85 M, F College 12 −.05–.58 .34
EPPS 92 M, F College 20 −.01–.79 .44
Finn (1986) MMPI factors 96 M 17–25 30 −.14–.58 .35
MMPI factors 78 M 43–53 30 .10–.88 .56
Helson & Moane (1987) CPI 81 F 21 22 .21–.58 .37
CPI 81 F 27 16 .40–.70 .51ACL 78 F 27 16 .49–.72 .61
Helson & Wink (1992) CPI 101 F 43 9 .73
ACL 96 F 43 9 .73
Note. CPI = California Psychological Inventory; 16PF = Sixteen Personality Factor Questionnaire; MMPI =
Minnesota Multiphasic Personality Inventory; KLS = Kelly Longitudinal Study; EPPS = Edwards Personal Pref -
erence Schedule; GAMIN = Guilford–Martin Inventory of Factors; ACL = Adjective Check List. Adapted from
Costa and McCrae (1997).
aPersonal communication, May 10, 1985.