Modeling intraindividual change in personality traits: findings from the normative aging study

To advance an intraindividual life-span approach to the issue of stability and change, we studied personality trait trajectories in adulthood. Growth curves for extraversion and neuroticism were estimated for over 1600 men (initially aged 43-91) in the Normative Aging Study, who were followed over 12 years. We found significant individual differences in intraindividual change for both traits, as well as different trajectories for extraversion and neuroticism. The overall extraversion trajectory was best defined by a linear model, but neuroticism was characterized by quadratic decline with age. We then considered several variables as predictors of individual differences around these overall trajectories. Birth cohort, marriage or remarriage, death of spouse, and memory complaints were all significant predictors, explaining variability in both level and rate of personality trait change. These findings suggest that there is a good deal of variability in personality trajectories, and that some of this variability can be explained by birth cohort as well as by age-graded life events.     

Lower cognitive test scores observed in alcohol abstainers are associated with demographic, personality, and biological factors: the PATH Through Life Project

AIMS: To identify variables that explain the association between alcohol abstention and cognitive performance. We hypothesized that demographic and personality variables would be important for explaining the association in all age cohorts, but that health variables would be more important in the older age-cohorts. DESIGN: Three age cohorts (20-24, 40-44, 60-64 years) were sampled randomly, yielding a total of 7485 participants, with data from 602 alcohol abstainers and 4158 light or moderate drinkers used in this study. Setting The sample was drawn from the cities of Canberra and Queanbeyan, Australia. MEASUREMENTS: Scales measuring demographic, health and personality variables and cognitive and physical tests were administered. Participants drinking at hazardous or harmful levels were excluded from the analysis. FINDINGS: A range of demographic and physical function measures were found to explain partially the finding of abstainers having lower cognitive test scores. The effects of independent variables were largest in the 60-64-year-old age group with a trend for physical variables such as lung function and grip strength to become more important in the older age groups. In the 20-24-year-olds, the majority of the effect remained unexplained. CONCLUSION: There is evidence that poorer cognitive test performance by abstainers reflects in part selection effects and poorer physical functioning, but does not appear to be due to mental or physical health conditions or personality.     

Stability and change in adult personality over 6 years: findings from the Victoria Longitudinal Study

Data from the Victoria Longitudinal Study were used to examine the 6-year longitudinal stability of personality in older adults. Personality was measured with the NEO Personality Inventory. The longitudinal sample consisted of 223 adults initially ranging from 55 to 85 years of age. Longitudinal confirmatory factor analyses were used to examine the stability of individual differences in change over time, and the stability of the longitudinal factor structure. The results indicated both substantial stability at the level of individual differences in change, as well as significant individual differences in change that were related to age and gender. Finally, the factor structure of personality was invariant over time but did not approximate simple structure for the five dimensions of personality. Our study of 6-year personality development provided both (a). a confirmation of early significant stability findings and (b). unique evidence for significant individual differences in late adulthood.     

Personality-ability relationships in aged adults

In an effort to investigate personality-ability interrelationships in older persons, 102 community-residing elderly persons were administered the Holtzman Inkblot Technique (HIT) and measures of both crystallized (Gc) and fluid (Gf) intelligence. Results suggested that each ability factor loaded on separate personality dimensions established in a previous analysis of HIT data using this sample. Whereas the personality factors labeled Anxiety Over Ideational Sufficiency and Feelings About Bodily Integrity loaded on Gc, factors termed Use of Cognitive Resources to Deal With Reality and Organizational Ability/Intellectual Functioning loaded on Gf. Causal inferences are difficult to make. However, these data suggest that individual differences in the maintenance of higher levels of intellectual functioning in later adulthood might be motivated by ego defensive mechanisms that act to insulate the older individual from feelings of self-worthlessness and failure and/or a loss of control over external forces via the development of intellectual skills.     

Monetary incentive, age, and cognition.

Results from studies of cohort differences suggest that older and younger volunteers may differ in aspects other than age. In this study subjects, who had or had not been promised $10.00 payment for their participation, were compared on certain personality and intelligence factors. No differences between incentive conditions were observed for 2466 potential subjects on willingness to participate, nor for 591 subjects eventually tested on their scores on the Primary Mental Abilities Test, the Test of Behavioral Rigidity and Cattell's 16 PF. However, differences by incentive condition were observed on the intercorrelation matrices for women on Form B of the 16 PF. Results of these analyses suggest that, with few exceptions, supplying a monetary incentive to induce subjects to participate in a study does not significantly alter the characteristics of a volunteer sample with regard to age or sex.     

Search for a common cause factor amongst cognitive, speed and biological variables using narrow age cohorts

BACKGROUND: Cross-sectional studies have demonstrated that age-related effects on many cognitive and biological functioning variables are shared. A number of theories postulate that these associations arise from a common causal mechanism responsible for change across a wide range of functions. However, it has been claimed that the finding of shared variance among variables in these studies may be spurious because most studies have been cross-sectional and based on age-heterogeneous samples. OBJECTIVE: To examine evidence for changes with age in variance shared by cognitive variables using a narrow-age cohort design. Methods: Three samples of adults with age ranges 20-24 years (n = 2,404), 40-44 years (n = 2,530) and 60-64 years (n = 2,510) were drawn from a population-based study. These groups were supplemented by data from an older sample of individuals (77 years and over) from a second population-based study (n = 374). Four models of the structure of a range of cognitive, speed and biological variables derived from previous cross-sectional research were fitted to data. These models were complete independence of variables within a cohort, a single common factor, multiple independent factors, and a second order factor model. RESULTS: Model fit and the magnitude of loadings from multiple-group confirmatory factor analyses was compared between age groups. The fit for all four models was worse in the 60-64 year age group. Factor loadings on the common factor specified in these models varied between the groups, but the speed factor rather than the biological factor showed increased loadings as a function of age. CONCLUSIONS: This narrow age-cohort study did not support the existence of developmental changes in the structure of cognitive and biological variables across the lifespan. Shared variation between measures of cognition and biological function may be an artifact of the research designs that have generated these findings. This casts doubt of the existence of a common causal mechanism. However, it may be that such changes manifest only in later old age.     

Age changes and differences in personality traits and states of the old and very old

The purpose of this study was to examine stability and change in personality traits and states for 3 age groups: centenarians, octogenarians, and sexagenarians. One hundred seventy-nine older adults participated in the 2-wave study. Results concerning age-group differences indicated that centenarians scored higher in Suspiciousness but lower in Intelligence and Stress when compared with the other 2 age groups. Octogenarians were lower in the personality traits Intelligence, Dominance, and Conscientiousness when compared with sexagenarians. Octogenarians were lower in the personality state Arousal, but higher on Regression. Results from the longitudinal analyses for centenarians indicated lower scores for Sensitivity, but higher scores for Radicalism (both personality traits), as well as higher scores of Fatigue and Depression (personality states) at follow-up. For the younger 2 age groups, age changes included higher scores for Sensitivity and Suspiciousness (personality traits). Stability scores for traits and states were considerably lower for centenarians when compared with the younger age groups.     

Personality dimensions and substance misuse: relationships in adolescents, mothers and fathers.

The research addressed the question of whether relationships exist between personality dimensions, antisocial behavior, and alcohol or other substance misuse (AOSM) in adolescents and in their fathers and mothers, who often also have histories of AOSM. One hundred male adolescents (mean age 15.8 years) entering a residential treatment center for youths with AOSM, their mothers (n = 88, mean age 39.4 years), their fathers (n = 36, mean age 44.9 years), and community controls (n = 100 adolescents, mean age 16.5 years; n = 96 mothers, mean age 43.8 years; n = 87 fathers, mean age 45.9 years) were recruited. All participants completed a personality questionnaire and were interviewed on several measures, including structured interviews for psychopathology and substance misuse. The findings indicated that novelty seeking (NS), one of the personality dimensions, was significantly correlated with substance misuse in adolescent probands, adolescent controls, and proband fathers and mothers, but not in control fathers and mothers. Regression analyses that included conduct disorder (CD) or antisocial personality disorder (APD) symptoms indicated that both NS and CD or APD symptoms made significant contributions to the prediction of substance misuse in treatment group probands and in their fathers and mothers. The findings further suggest that NS and antisocial behaviors contribute independently to substance misuse in severely impaired adolescents and their fathers, but not in their mothers.     

Monetary incentive,age, and cognition

Abstract

Results from studies of cohort differences suggest that older and younger volunteers may differ in aspects other than age. In this study subjects, who had or had not been promised $10.00 payment for their participation, were compared on certain personality and intelligence factors. No differences between incentive conditions were observed for 2466 potential subjects on willingness to participate, nor for 591 subjects eventually tested on their scores on the Primary Mental Abilities Test, the Test of Behavioral Rigidity and Cattell's 16 PF. However, differences by incentive condition were observed on the intercorrelation matrices for women on Form B of the 16 PF. Results of these analyses suggest that, with few exceptions, supplying a monetary incentive to induce subjects to participate in a study does not significantly alter the characteristics of a volunteer sample with regard to age or sex.     

Influence of age and sex on 19 blood variables in healthy subjects.

Normal values exist for all clinical chemical tests, but it is not very clear what is normal for healthy elderly subjects. Therefore, routine blood variables were determined in 80 ambulatory, disease-free persons who had undergone rigorous health screening. The subjects were divided into the following age groups: 20 (+/- 3), 40 (+/- 3), 60 (+/- 3), and 80 (+/- 5) years, with 10 males and 10 females per age group. Blood variables were determined after an overnight fast. It was found that even with conservative statistical measures more than half of the variables were significantly affected by age or sex. Significant age differences were found for total cholesterol, triglycerides, sodium, and ASAT. Urea, creatinine, gamma-GT, phosphate, alkaline phosphatase, and albumin were characterized by both age and sex differences. No age or sex differences were found for glucose, potassium, chloride, calcium, calcium ion, iron, magnesium, total protein, and ALAT. The findings suggest that the age or sex-related changes of a number of blood variables such as cholesterol, triglycerides, and liver enzymes are not only of statistical significance, but are also of clinical relevance.     

Disparate time spans in sequential studies of aging.

In several published studies of intelligence and adult age, a sequential design was used in which birth cohort and time of measurement were the independent variables in an ANOVA. The time span of these two variables were quite disparate; the cohort variable covered about 50 years whereas the time-of-measurement variable covered 7 or 14 years. It was demonstrated here that when time spans are disparate, even when all differences are attributable entirely to age changes, the F values typically will be larger for the cohort variable and errors in interpretations became likely. When cohort differences are statistically significant and time-of-measurement differences are not, the conclusion that age differences are "generational" and not due to age changes within individuals may be wrong.     

Perceived changes in well-being: the role of chronological age, target age, and type of measure

The goal of this study is to investigate whether perceived changes in one's well-being from the present to the future are related to chronological age, target age, and type of measure (psychological well-being versus life satisfaction). Young adults (N=114) rated their current well-being and their future well-being at one of three target ages (30, 50, or 70 years old) and middle-aged adults (N=51) rated their current well-being and future well-being at the target age of 70 years old. Future self-enhancement effects were observed on both measures of well-being for young adults and on life satisfaction for middle-aged adults. Future self-enhancement effects were greater for life satisfaction than for psychological well-being. One-way MANOVAs showed that there were chronological age differences but not target age differences in the magnitude of future self-enhancement effects for well-being. Future self-enhancement effects were larger for young adults than for middle-aged adults.     

Methodological comment: temporal stability of older person's spontaneous self-definition

Open-ended tasks such as the "Who am I?" (Bugental & Zelen, 1950) or the Twenty Statement Test (Kuhn & McPartland, 1954) have facevalidity with regard to assessing content and dimensions of self-definition. Examined in the present study were questions about short-term temporal stability. Theory suggests that measures of the self may better reflect intraindividual variability than personality tests. Free-response and card-sort versions of the "Who am I?" were completed twice over an 8-week period by a volunteer sample of older persons (N = 104; age range: 69-92 years, M = 79). Low temporal stability of self-definition was found on an intraindividual level and on the level of interindividual differences. Measures of personality showed high stability. Although the "Who am I?" may not be the best instrument for assessing the content aspects of self-definition that are stable over time and across situations, it may provide a measure of situation-related variability.     

Cross-sectional age differences and longitudinal change on the Bradburn Affect Balance Scale

Cross-sectional age differences and longitudinal change were examined on psychological well-being, positive affect, and negative affect, as measured by the Bradburn Affect Balance Scale. Data were collected from 1,159 participants in 1971 and 1985. Cross-sectional analyses showed age differences: older cohorts reported greater overall well-being but lower levels of both positive and negative affect when compared to younger respondents. Longitudinal analyses indicated small but significant changes toward decreased positive and negative affect but increased overall well-being. Negative affect had the strongest effect size. Positive and negative affect showed different patterns of change for different age groups. Taken together, cross-sectional and longitudinal findings suggest that change in affect variables is age-related, although these changes are relatively small. More evident was a pattern of correlational stability with age. Finally, the pattern of the results supports a two-factor theory of psychological well-being.     

Longitudinal analyses of psychological well-being in a national sample: stability of mean levels

Maturational changes, cohort differences, and time of measurement effects on psychological well-being were examined in data from the National Health and Nutrition Examination Survey (NHANES) I Epidemiologic Followup Study. A 9-year longitudinal study of 4,942 men and women initially aged 25 to 74 was supplemented by cross- and time-sequential analyses using an independent sample of 4,986 participants who were first administered the well-being measures at the time of the follow-up. Older participants in the study tended to be lower in both Positive and Negative Affect, but longitudinal changes in these two subscales were not found, and Total Well-Being showed no significant age, birth cohort, or time effects in any of the analyses. Given the size and representativeness of the sample, this is strong evidence of the stability of mean levels of psychological well-being in adulthood, and points to the importance of enduring personality dispositions and processes of adaptation in determining levels of well-being.     

Age differences in perceptual style,selective attention,and perceptual-motor reaction time

One hundred seventy-five females ranging in age from 17 to 72 years, who were placed into one of seven age groups, were administered tasks measuring perceptual style, selective attention, simple choice, and complex reaction time. Multivariate and univariate analysis indicated there were significant differences between the age groups for all dependent measures. Trends manifest in the data suggest significant declines on the investigated information-processing ability measures begin in the late-40′s. This finding appears to indicate an over-all general decline on all information-processing variables rather than selective drop-out of abilities. Theoretical and applied implications of the results are discussed.     

Intellectual and personality differences between community-living and institutionalized older adult females

The purpose of the present study was to investigate simultaneously differences between normal institutionalized older adults and community-living older adults with respect to intelligence/cognitive test performance and personality. Participants were 25 community-living females (M age = 72.9 yrs, SD = 6.34) and 25 institutionalized females (M age = 80.0 yrs, SD = 6.46). Intellectual/cognitive ability was assessed by the WAIS, Stanford-Binet Intelligence Scale (Form L-M), Ravens Coloured Progressive Matrices; personality was assessed by the Hand Test, a projective technique. Several multivariate analyses (discriminant analysis) were conducted. Results suggested that even when controlling for age and level of education, institutionalization appears to be associated with intellectual/cognitive as well as personality deficits. The findings were discussed in terms of the potential implications for the professional working with institutionalized older adults.     

Age, personality, and the spontaneous self-concept

Kuhn and McPartland's (1954) Twenty Statements Test (TST) was examined as a measure of the spontaneous self-concept. In the first study, using 60 men and 60 women aged 32 to 84, responses were scored to indicate the salience of different aspects of self-concept content; global ratings of five personality dimensions and self-esteem were also made and compared to scores on the NEO Personality Inventory. Although age itself was infrequently mentioned, there were some age differences in the salience of different elements of the self-concept, and older individuals scored somewhat lower on TST-rated Neuroticism. In the second study, age identification and self-esteem were considered in the responses of 245 men and women. As in Study 1, self-esteem was related to low Neuroticism and high Extraversion, but was unrelated to age. Social structural variables like age are reflected in the content of the spontaneous self-concept, but personality traits appear to be more important in explaining self-esteem.     

Relationship of age of first drink to child behavioral problems and family psychopathology

BACKGROUND: Studies have implicated a wide variety of variables as being associated with an early age of first drink (AFD). AFD in turn has been associated with a variety of negative outcomes in adolescence and early adulthood. This study is designed to quantify the contributions of these antecedent variables to prediction of AFD; in particular it will carefully examine the involvement of variables in four areas (child characteristics, family demographics, family psychopathology, and child behavior problems). METHODS: Using data from a multicenter study on alcoholism, we first investigated the differences between two groups of children (ages 7 to 17 years), one from families heavily loaded for alcohol dependence and the other from population controls. Second, a multidomain, multistep regression model using child characteristics, family demographics, family psychopathology, and child behavior problems was performed to determine significant contributors to predicted AFD. RESULTS: Five variables initially contributed to the prediction of AFD. These included gender, age at interview, the number of adult sibs with alcohol dependence, being held back a year in school, and conduct scale score. However, the number of conduct symptoms appeared to contain the contributions of gender and being held back a grade in school, and these two variables were subsequent removed from the model. The remaining three variables explained 45% of the model variance; age at interview accounted for 38.3%, conduct scale score accounted for 6.2%, and the number of alcohol-dependent adult sibs accounted for 0.5%. No family history measures of alcohol dependence or antisocial personality disorder were contributory to the prediction model for AFD. CONCLUSIONS: Both the "number of conduct symptoms" and the "number of adult sibs with alcohol dependence" are inversely associated with predicted AFD. The latter variable appears marginally predictive of AFD and suggests a condition in which the child's household, regardless of strength of family history of AD (or antisocial personality disorder), appears conducive to early drinking. Thus, child and environmental factors are stronger predictors of age of first drink than family history.     

Questionnaire, walking time and button test measures of functional capacity as predictive markers for mortality in rheumatoid arthritis

Mortality over 9 years in rheumatoid arthritis was studied according to baseline demographic, disease, therapy and comorbidity variables, and measures of functional capacity variables. Significant differences between patients who survived and died over the next 9 years were seen for 8 variables: age, joint count, oral corticosteroid use, presence of concurrent heart disease, formal educational level, and 3 quantitative measures of functional capacity, questionnaire responses regarding activities of daily living, modified walking time and the button test. Five-year survivals of 50% or less were seen in patients with severely dysfunctional values for the 3 quantitative measures of functional capacity. Increased relative risk of mortality according to functional capacity measures was not explained by age, sex, duration of disease, smoking history, joint count, hand radiograph score, grip strength, morning stiffness, formal educational level, oral corticosteroid or parenteral gold use, or various comorbidities, and was not expected by a majority of physicians.