A Cultural Comparison of Personality Profiles of U.S. and Japanese Centenarians

Abstract

The purpose of this study was a cross-cultural examination of centenarians’ personality through a person-centered approach to examine if there is a “resilient” personality profile consistent across cultures. Proxy reports information was obtained from family and close friends of 239 U.S. centenarians from the Georgia Centenarians Study and 272 Japanese centenarians from the Tokyo Centenarian Study. Latent profile analyses were conducted to identify personality profiles in centenarians from the United States and Japan. Two personality profiles were identified in both samples: a “resilient” personality profile and “nonresilient” personality profile. The “resilient” group had higher levels of positive personality traits with higher scores on agreeableness and extraversion and lower scores on neuroticism, conscientiousness, and openness. The “nonresilient” group had higher scores on neuroticism and lower scores on extraversion, openness, agreeableness, and conscientiousness. Fifty percent of U.S. centenarians and 65% of Japanese centenarians were in the “resilient” group.

Keywords

centenarians personality profiles NEO FFI United States Japan cross-cultural research

Centenarians are exceptional survivors and previous studies have indicated personality traits are associated with healthy aging (Roberts et al., 2007) and longevity (Gondo et al., 2006; Law et al., 2014; Martin et al., 2006; Masui et al., 2006). Based on the Big-Five personality model, centenarians have a unique set of personality traits that contribute to longevity (Law et al., 2014). Longevity for Japanese centenarians was associated with high levels of extraversion, openness, and conscientiousness (Masui et al., 2006). A population of U.S. centenarians in Georgia had low levels of neuroticism, high levels of extraversion, and high levels for facets of openness, agreeableness, and conscientiousness (Martin et al., 2006). Another study examining the personality traits of a population of Ashkenazi Jewish centenarians noted that centenarians have low levels of neuroticism and high levels of conscientiousness compared to U.S. population means from both self-report and informant-report groups (Kato et al., 2012). Across cultures, common personality traits according to the Big-Five factor personality model were associated with longevity. Centenarians have lived past their contemporaries and they may have a “resilient” personality profile rooted in the composition of the Big-Five-Factor personality model.

The purpose of this study was to examine if there is a “resilient” personality profile consistent for U.S. and Japanese centenarians. Personality profiles are groupings of individuals into distinct profiles according to a person-specific configuration of the five-factor model of personality (Asendorpf, 2015). Allik and McCrae (2004) in a large-scale study examined the distribution of personality profiles across cultures and observed that cultures closer together in geographic proximity shared similar personality profiles. However, the personality profiles of individuals from Japan were more similar to European cultures than to East Asian cultures (e.g., South Korea, Taiwan, Allik & McCrae, 2004). A cross-cultural study of centenarians’ personality profiles allows for an examination of similarities and differences in personality profiles across cultures. Prior cross-cultural studies of personality have primarily examined mean levels or age-related changes in personality rather than personality profiles across cultures (Allik, 2005; Chopik & Kitayama, 2018; Costa et al., 2001; Ferguson, 2010). In addition, cross-cultural studies of personality have focused on the factor structure or the invariance of the five-factor personality model across cultures (Church et al., 2011; McCrae & Costa, 1997), and participants primarily consisted of college students (Allik & McCrae, 2004; McCrae & Terracciano, 2005). Yet, an examination of personality profiles is very much needed in order to know which configuration of personality traits comprise a resilient personality profile among centenarians and whether they are consistent across cultures.

Resilience in terms of personality characteristics has two approaches: ego-resiliency and trait resilience (Oshio et al., 2018). Trait resilience focuses on trait orientation or personality characteristics of resiliency. Hu et al. (2015) defined trait resilience as a personal trait that allows individuals to adjust and overcome adversity. Resilience is viewed as a positive personality characteristic that leads to effective adaptation. The other approach is ego-resiliency, a person-centered approach to identify personality profiles. The methodology of a person-centered approach is to group individuals according to shared personality trait characteristics and similar personality structure—subsequently differentiating groups not sharing the same personality structure.

Specht et al. (2014) in an overview of research examining personality profiles noted most studies focus on age groups younger than 30 years of age. Three personality profiles using the Big-Five personality traits have been proposed and tested with children: resilient, overcontrolled, and undercontrolled profiles (Caspi, 1998; Robins et al., 1996). Resilient individuals have low average scores on neuroticism and high mean scores on extraversion, openness, agreeableness, and conscientiousness. Overcontrollers are described as having higher mean levels of neuroticism and lower levels of extraversion, and undercontrollers are characterized by having low average scores in conscientiousness and agreeableness (Asendorpf et al., 2001; Robins et al., 1998). Among older age groups, a higher number of resilient individuals have been observed compared to younger age groups, and personality profiles are similar across men and women (Specht et al., 2014). Further studies examining the personality profile of older age groups are needed to understand the configuration of personality traits that constitute a resilient profile in later life.

This study used a person-centered approach to examine shared configuration of Big-Five personality traits that constitute a resilient personality profile among U.S. and Japanese centenarians. Previous studies examining the personality traits of centenarians through the Big-five-factor personality model compared centenarians’ personality traits with defined population norms for the NEO-FFI and also compared centenarians’ personality traits with an age-matched sample of older adults aged 65–97 (Law et al., 2014). Law et al. (2014) reported that centenarians had higher neuroticism and lower extraversion and openness compared to the general population. In addition, centenarians’ had higher neuroticism, lower extraversion, openness, and conscientiousness than the closest age-matched sample. A study of Japanese centenarians comparing centenarians’ personality scores with a predicted personality score for a 100-year-old from younger controls revealed centenarians had higher extraversion, openness, and conscientiousness (Masui et al., 2006). These studies examined personality traits of centenarians and compared across closest age matching samples, and a projected personality score from younger controls. However, they did not examine personality traits according to shared configuration or groups of personality profiles through a person-centered approach.

Only a few studies have classified centenarians by shared configuration of personality traits or groups of personality profiles through the Big-five-factor personality model. Martin et al. (2006) investigated configurations of personality traits among U.S. centenarians. Self- and proxy reports indicated that centenarians had low levels of neuroticism and higher levels of extraversion, competence (a facet of conscientiousness), and trust (a facet of agreeableness). Martin et al. (2006) concluded that centenarians and their proxies agreed on personality reports but centenarians were more likely to report higher levels on the personality traits compared to proxy reports. In a second study, Martin et al. (2009) concluded that centenarians with low levels of neuroticism and high scores on extraversion, openness, and conscientiousness, and centenarians highly engaged in life were more likely to report better mental status. In addition, lower levels of emotional stability, extraversion, openness, agreeableness and conscientiousness, and lower levels of engagement in life were more commonly found among centenarians with poor mental status. Lastly, Martin (2007) noted centenarians with a configuration of resilient personality traits had low levels of neuroticism (i.e., high emotional stability), and high levels of extraversion and conscientiousness.

An important point to highlight when examining the personality profile of centenarians is the prevalence of dementia. Andersen-Ranberg et al. (2001) observed in a study of Danish centenarians, the prevalence of mild, moderate, and severe forms of dementia is 51%. Another study examining the prevalence of dementia in a sample of centenarians in Northern Georgia found 52.3% of centenarians having some form of dementia (Poon et al., 2012). However, Ishioka and Gondo (2017) noted dementia prevalence for centenarians is influenced by the definition according to diagnostic criteria. The prevalence of dementia increases when questionable cases are defined as dementia. Overall, dementia prevalence for centenarians is high, and it may be due to a number of risk factors (Ishioka & Gondo, 2017).

The Big-five-factor model of personality has been utilized to examine personality changes related to dementia. Strauss et al. (1993) evaluated personality ratings of dementia patients through two informants (primary caregiver and relative). The results indicated an increase in neuroticism, decrease in extraversion, openness, and conscientiousness. In addition, similar results were observed by Siegler et al. (1994), who examined personality of older adults after diagnosis of Alzheimer’s disease. These results indicate that dementia or Alzheimer’s disease can affect the current personality profile of centenarians.

In summary, the study of personality profiles of centenarians is still in its infancy; only a few studies have been conducted in examining a shared configuration or groups of personality profiles of centenarians through a person-centered approach. In addition, no study has been conducted across cultures investigating whether they are universal in U.S. and Japanese centenarians.

In this study, through an examination of personality profiles across U.S. and Japanese centenarians, we addressed these three research questions: (1) Which personality profiles can be identified in centenarians? (2) Are the personality profiles similar or different across cultures? and (3) Are there demographic (i.e., gender, ethnic, residential status, education, and mental status) differences between individuals identified as demonstrating these personality profiles?

Method

Participants and Procedures

The study included centenarians from Phase 3 of the Georgia Centenarian Study (GCS; Poon et al., 2007) and from the Tokyo Centenarian Study (Gondo et al., 2006). The participation rate for the Georgia sample was 67.2% and somewhat higher than the participation rate of Tokyo centenarians (43.0%, Martin et al., 2018).

Georgia Centenarian Study (Phase 3)

This study included 239 U.S. community-dwelling and institutionalized centenarians and near centenarians (98–109 years of age) and their proxies who are part of a population-based study. The names of the participants were obtained from voter registration rolls for the State of Georgia and from calls to a random subset of long-term care facilities. Centenarians were first contacted by telephone and mail, and follow-up face-to-face interviews were conducted. Table 1 indicates that the U.S. participants were more likely to be women (82%), White/Caucasian (75%), and to live independently in private homes (45%). Proxy information about the centenarians was obtained for all of the personality measures. Table 1 displays demographic characteristics of the Georgia centenarians along with information about proxy informants.

Table 1

Demographic Characteristics of Complete Sample.

Demographic characteristics	United States (GCS)	Japan (TCS)	Chi-square
Number of centenarians	N = 239	N = 304	–
Age in years M (SD)	99.7	100.8	–
Gender			1.23
Women	82%	79%	–
Men	18%	21%	–
Ethnicity			–
White/Caucasian	74.5%	–	–
Black/African-American	25.5%	–	–
Asian	–	100%	–
Education			8.56*
Less than high school	41%	41%	–
High school completed	30%	40%	–
College/post graduate	29%	19%	–
Residential status			–
Private home	45%	68%	–
Personal care home	18%	–	–
Nursing home	37%	26%	–
Hospital	–	7%	–
Marital status			21.30***
Married	4%	1%	–
Separated	0%	1%	–
Divorced	4%	0%	–
Widowed	87%	96%	–
Never married	5%	1%	–
NEO personality factors			–
Neuroticism	16.91 (7.68)	18.98 (6.37)	–
Extraversion	26.54 (6.57)	27.98 (6.28)	–
Openness to experience	20.13 (5.44)	22.36 (4.97)	–
Agreeableness	32.83 (7.63)	31.25 (7.79)	–
Conscientiousness	30.70 (6.36)	32.02 (6.84)	–
MMSE			–
Total summary score	17.09 (8.99)	12.45 (8.64)	–

Abbreviations: GCS = Georgia Centenarian Study; TCS = Tokyo Centenarian Study; MMSE = The Mini-Mental Status Examination.

Note. Because of rounding, percentages may not add to 100. *p < .05. **p < .01. ***p < .001. The majority of proxies for the US sample were daughters (40%), sons (15%), granddaughters (8%), nieces (8%) and wives (6%). Among the Japanese proxies, 54% were the centenarians’ child, 19% the spouse of their child, 13% facility staff, and 4% a grandchild. The NEO-FFI contained 60 statements and proxy participants responded to the items from the NEO using a five-point scale where SD = strongly disagree (=0), D = disagree (=1), N = neutral (=2), A = agree (=3), and SA = strongly agree (=4). The MMSE questions were rated on a dichotomous scale, coded 1 = no, and 2 = yes. Standard deviations in parentheses.

Tokyo Centenarian Study

This study included 304 Japanese centenarians and their proxies from the Tokyo metropolitan area. The centenarians’ mean age was 101 years (SD = 1.3), with an age range from 100 to 106 years. The Tokyo Centenarian Study (TCS [Gondo et al., 2006] was initiated in 2000 with a semi total population sample of centenarians recruited from residential lists. In the TCS, Japanese centenarians were more likely to be women (79%), had lower levels of education (41%), and were more likely to live in a private home (68%).

Table 1 also presents the results of comparison testing for differences between the U.S. and Japanese centenarians on some of the demographic variables for the complete sample. Results suggest significant cultural differences for education and marital status,χ²(2, N = 473) =8.56, p < .05 and χ²(4, N = 514) =21.30, p < .001, respectively. The cross-cultural comparison indicates that 30% of U.S. centenarians’ highest educational attainment was the completion of high school compared to 40% of Japanese centenarians. An additional 29% of U.S. centenarians achieved a college/post college education along with 19% of Japanese centenarians. Our findings indicate that more U.S. centenarians (5%) never married compared to only 1% of Japanese centenarians. Moreover, 4.2% of U.S. centenarians were currently married compared to 1.4% of Japanese centenarians. Lastly, 4% of U.S. centenarians were divorced compared to 0% of Japanese centenarians. We found that 99% of Japanese centenarians had been married at some point in time compared to 95.4% of U.S. centenarians.

Measures

Demographic Variables

In this study, demographic variables included age, gender (0 = male, and 1 = female), ethnicity/race (0 = Caucasian, 1 = African American; only assessed in the U.S. sample), culture (0 = U.S. American, 1 = Japanese), education (1 = less than high school, 2 = high school completed, and 3 = college/post college), residential status (0 = private home, 1 = personal care home, 2 = hospital, and 3 = long-term care facility), and marital status (1 = currently married, 2 = living with a partner, 3 = separated, 4 = divorced, 5 = widowed, and 6 = never married).

Personality Reported by Proxies

For a direct comparison between both samples, the same items of the NEO Five-Factor Inventory (NEO-FFI; Costa & McCrae, 1992) were used in both U.S. and Japanese study. The Japanese version (Shimonaka et al., 1999) of the NEO-FFI was used in the Japanese study. The NEO-FFI contained 60 statements and has five factors: neuroticism, extraversion, openness, agreeableness, and conscientiousness; and each factor has 12 questions. The items were added and a summary score for each personality domain was obtained, ranging from 0 to 48. A higher score in both measures suggest a higher level of the personality domain being measured. In order to obtain a larger number of responses, proxy reports were used to assess centenarians’ personality traits. Reliability (coefficient alpha) was computed in SPSS. Reliabilities in the U.S. study for each personality dimension were .82 for neuroticism, .78 for extraversion, .72 for openness (after deleting the item, “she/he believes we should look to our religious authorities for decisions on moral issues”), .87 for agreeableness, and .83 for conscientiousness. In the Japanese study the reliability was .77 for neuroticism, .80 for neuroticism, .61 for openness (after deleting the item, “she/he believes we should look to our religious authorities for decisions on moral issues”), .89 for agreeableness and .86 for conscientiousness. In this study, we used proxy reports of centenarians’ personality. The items were added, and a summary score for each personality domain was obtained, ranging from 0 to 48.

Studies using individual self- and proxy reports have demonstrated a high level of agreement between both sources of data. For example, McCrae (1982) found a significant level of agreement between raters, with the highest level of agreement between self-reports and spouse ratings. Riemann et al. (1997) also found strong agreement between self-reports and peer ratings, with a correlation of .55 for the NEO-FFI. Martin (2007) compared centenarians’ reports and their proxy reports on centenarians’ personality traits, and concluded that centenarians were more likely to report their personality traits as extreme. In addition, both reports had an agreement on the level of the personality traits (Martin, 2007).

Cognitive Health

The Mini-Mental Status Examination (MMSE; Folstein et al., 1975) was administered to assess cognitive health. The MMSE has 11 items with scores ranging from 0 to 30. A higher score indicates better cognitive health. The MMSE is a well-known and frequently used screening device for mental status functioning. In this study, a summary score was used to assess mental status in older adults. In this study, we used a lower MMSE cutoff because of the high prevalence of centenarians with sensorimotor limitations, placing them at a disadvantage (Holtsberg et al., 1995). Centenarians with MMSE <17 were considered in poor cognitive health, and MMSE scores of 17 and above were considered to be in moderate to high cognitive health.

Statistical Analyses

Analyzing data in the present study involved two steps. First, to identify personality patterns in centenarians, two latent profile analyses were performed in each sample using Mplus 5.0 (Muthén & Muthén, 2007). Latent profile analysis (LPA) classifies individuals into groups based on their shared characteristics. The purpose of using LPA was to determine if there is a resilient personality profile for both U.S. and Japanese centenarians. LPA uses continuous outcomes to classify and cluster individuals into group categories. We examined classification accuracy of the best final solution obtained in our LPA. The number of classes was determined by considering statistical indicators such as Lo–Mendell–Rubin (LMR; Lo et al., 2001) and Vuong–Lo–Mendell–Rubin (VLMR). Muthén and Muthén (2000) presented four criteria to decide the optimal number of latent classes in mixture models, including Bayesian information criteria (BIC) and a sample-size adjusted version of the BIC (Adj. BIC), entropy, and the bootstrapped likelihood ratio test (BLRT). In LPA, the goodness-of-fit indices are not “sample size free”; values are influenced by the number of participants. Therefore, it is important to consider other indicators of fit that are “sample size free.” The fit statistics, interpretability of the classes, and sample size for each personality subgroup were evaluated before deciding on the best number of classes for each sample. Other analyses were conducted using SPSS.

After determining the latent personality profiles, additional analyses were conducted to compare centenarians who were classified as representing each profile on gender, ethnicity, residential status, education, and mental status differences in selected latent classes. These analyses were done separately because some of the demographic variables were not comparable across samples. A crosstabulation analysis was performed to test for cultural differences on the identified personality latent profiles.

Results

Results are presented in two sections. First, results regarding the identification of latent personality profiles are presented and cultural differences on the profiles are examined. Second, crosstabulation results for gender, ethnicity, residential status, education, and mental status differences are presented for the two-class personality solution for U.S. and Japanese centenarians.

Latent Profile Analyses

We performed a series of latent personality profile analyses (LPA) separately for the centenarians from the United States and Japan. Table 2 displays the model fit indices for the two-, three-, and four-class model solutions for the two groups. Changes in the goodness-of-fit statistics were evaluated as groups were added. The LPA results for the U.S. sample indicated the four-class model appeared to fit better than the three-class solution because of the lower values for the AIC, BIC, and adjusted BIC as well as higher entropy level. The VLMR and LMR indices do not support the four-class solution; instead, these measures indicate that the two-group solution provides the best fit to the U.S. centenarian personality data. The p-values for the BLRT _p were all statistically significant, supporting all three models.

Table 2

Comparisons of Model Fit Indices of Personality Traits for U.S. and Japanese Centenarians.

	Akaike (AIC)	BIC	Adjusted BIC	Entropy	VLMR_p	LMR_p	BLRT_p
U.S. sample
2 groups	7,396.520	7,451.389	7,400.680	0.687	0.0020	0.0023	0.0000
3 groups	7,345.502	7,420.948	7,351.222	0.749	0.0860	0.0909	0.0000
4 groups	7,321.121	7,417.143	7,328.402	0.806	0.2132	0.2218	0.0000
Japanese sample
2 groups	8,491.889	8,549.225	8,498.496	0.694	0.0000	0.0000	0.0000
3 groups	8,471.651	8,550.488	8,480.736	0.721	0.4131	0.4220	0.0000
4 groups	8,457.534	8,557.872	8,469.096	0.744	1.0000	1.0000	0.0128

Note. BIC = Bayesian Information Criterion; VLMR = Vuong–Lo–Mendell–Rubin; LMR = Lo–Mendell–Rubin; BLRT = Bootstrap Likelihood Ratio Test.

For the four-class solution, one group included only a few centenarians (i.e., n = 6 which consisted of 3% of the sample), indicating that the four-class solution did not represent the U.S. sample well. After analyzing the classes projected on the graph for the three-class solution (not shown) two groups in the U.S. sample did not appear to differ on the personality variables. We therefore selected the two-group solution as providing the best fit to the personality data for the U.S. centenarian sample.

Table 2 also shows the goodness-of-fit statistics for two-, three-, and four-class LPA solutions for the Japanese centenarians. Several statistics fit indices were obtained from the LPA and examined to determine the best number of classes. The lower values for the BLRT _p (p = 0.00), BIC, LMR _p (p = 0.00), and VLMR _p (p = 0.00) clearly indicate that the two-class solution model provides a better fit to the personality data than the one-class solution for the Japanese sample. Values for the BLRT _p slightly increased from the three- to four-class solution, but the BLRT _p values were statistically significant for all three models. These values did not clearly indicate the best number of Japanese centenarian classes. The lower values on the AIC, Adjusted BIC, and higher entropy values indicate that the four-class group solution model is better than the three-class solution. However, the BLRT _p (p < 0.001), VLMR (p < 0.001), and LMR _p (p < 0.001) were statistically significant and support the two class solution. We also examined the number of individuals in each group for all three solutions to determine whether there were enough centenarians in each group. The four-class solution includes one subgroup with only a few centenarians (i.e., n = 12 which consisted of 4% of the sample). For the three-class solution, the plots (not shown) suggest that two groups do not seem to differ on the personality dimensions. After considering inconsistencies and variations in the goodness-of-fit the best number of groups, we also selected the two-group solution for the Japanese sample.

Figure 1 displays estimated means for the two classes on the five personality traits for the U.S. and Japanese centenarians. Results for the U.S. sample indicate that the Class 1 and Class 2 groups had the same number of U.S. centenarians. Class 1 (n = 114, 50%) consisted of U.S. centenarians who received high mean scores from proxies on neuroticism and low mean scores on extraversion, openness, agreeableness, and conscientiousness (Costa & McCrae, 1992). Class 2 (n = 114, 50%) consisted of U.S. centenarians who received from proxy raters low mean scores on neuroticism and openness along with high mean scores on extraversion and agreeableness (Costa & McCrae, 1992). When examining differences between the two-group personality profiles for the U.S. sample, results suggest the two groups differed significantly on levels of neuroticism, t(226) = 13.36, p < .001, extraversion t(225) = −12.23, p < .001, openness t(225) = −4.80, p < .001, agreeableness, t(226) = −9.75, p < .001, and conscientiousness t(226) = −11.12, p < .001. Table 3 displays the means, standard deviations, t-test results, and effect sizes. These results indicate that U.S. centenarians in Class 2 received significantly lower scores from proxies on neuroticism and higher scores on extraversion, openness, agreeableness and conscientiousness compared to U.S. centenarians in Class 1. Centenarians in Class 1 can be labeled as the nonresilient group characterized by proxy raters as showing U.S. centenarians with higher levels of neuroticism and lower levels of extraversion, openness, agreeableness and conscientiousness (Costa & McCrae, 1992). By contrast, U.S. centenarians in Class 2 can be labeled the resilient group because centenarians from this group were rated by proxies as being lower on neuroticism, openness, and conscientiousness and higher on extraversion and agreeableness (Costa & McCrae, 1992). The resilient group was rated by proxies as higher on extraversion and lower on neuroticism and agreeableness compared to centenarians in the nonresilient group.

Figure 1

Mean personality profiles for U.S. and Japanese centenarians for two-class solution.

Table 3

Independent Group t-Test Between Personality Traits and Profile Groups for U.S. and Japanese Centenarians.

	Resilient		Nonresilient		t-test	Cohen’s d
	M	SD	M	SD	t-test	Cohen’s d
Neuroticism	11.85	4.84	21.97	6.48	13.36***	1.82
Extraversion	30.66	4.97	22.38	5.23	−12.23***	1.62
Openness	21.78	5.18	18.47	5.20	−4.80***	.64
Agreeableness	36.97	5.52	28.69	7.19	−9.75***	1.29
Conscientiousness	34.47	4.29	26.92	5.84	−11.12***	1.47

	Resilient		Nonresilient		t-test	Cohen’s d
	M	SD	M	SD	t-test	Cohen’s d
Neuroticism	16.66	5.53	23.16	5.62	8.74***	1.17
Extraversion	30.14	5.71	24.03	5.30	−8.31***	1.11
Openness	23.88	4.38	19.62	4.82	−7.02***	.93
Agreeableness	35.36	5.27	24.07	6.08	−15.32***	1.98
Conscientiousness	34.63	5.37	27.14	6.65	−9.64***	1.24

Abbreviations: M = Mean; SD = Standard Deviation.

Note. U.S. centenarians top. Japanese centenarians below. *** p < .001.

Figure 1 also shows estimated means for the two personality profiles for the Japanese centenarians. Class 1 (n = 98, 35%) was the smaller centenarian group (labeled the nonresilient group) and consisted of Japanese centenarians who received from proxy raters high mean scores on neuroticism and low mean scores on extraversion, openness, agreeableness, and conscientiousness (Costa & McCrae, 1992). Class 2 (n = 166, 65%) was the resilient group and included Japanese centenarians who received higher mean scores on extraversion and agreeableness as well as lower mean scores on neuroticism, openness, and conscientiousness (Costa & McCrae, 1992). When examining differences between the two-group personality profiles for the Japanese sample, results suggest the two groups differed significantly on levels of neuroticism t(242) = 8.74, p < .001, extraversion t(249) = −8.31, p < .001, openness t(241) = −7.02, p < .001, agreeableness, t(245) = −15.32, p < .001, and conscientiousness t(248) = −9.64, p < .001. Table 3 displays the means, standard deviations, t-test results, and effect sizes. Therefore, the results for the Japanese sample indicated Japanese centenarians in Class 2 received significantly lower scores from proxies on neuroticism and higher scores on extraversion, openness, agreeableness, and conscientiousness compared to Japanese centenarians in Class 1. Just like in the U.S. sample, centenarians in Class 1 can be labeled as the nonresilient group characterized by proxy raters as showing Japanese centenarians with higher levels of neuroticism and lower levels of extraversion, openness, agreeableness, and conscientiousness (Costa & McCrae, 1992). By contrast, Japanese centenarians in Class 2 can be labeled the resilient group because centenarians from this group were rated by proxies as being lower on neuroticism, openness, and conscientiousness and higher on extraversion and agreeableness (Costa & McCrae, 1992).

Demographic and Cultural Differences in Personality Profiles

Table 4 shows crosstabulation results concerning differences between the two personality classes on gender, ethnicity, residential status, education, and mental status for the U.S. and Japanese centenarians. Results for the U.S. sample indicate significant residential (χ²[2, 228] =6.21, p = .045), educational (χ²[2, 177] =9.60, p = .008), and cognitive health (χ²[1, 226] =7.28, p = .007) differences between the two groups. The results indicate that 27 % of U.S. resilient centenarians lived in long-term care facilities compared to 42 % of nonresilient U.S. centenarians. United States centenarians with lower levels of education were more likely (51.7%) to be in Class 1 (the nonresilient group), whereas U.S. centenarians with either high school (35.6%) or college/post college degrees (35.6%) were more likely to be classified in the resilient group. In addition, results for cognitive health suggest that 52.6% of U.S. centenarians in poor cognitive health were in Class 1 (nonresilient group) whereas 34.8 % of U.S. centenarians in poor cognitive health were in Class 2 (resilient group). No significant gender and ethnic differences were found between the nonresilient group and the resilient group for U.S. centenarians.

Table 4

Demographic Differences in Two Group Class Personality Profiles in U.S. and Japanese Centenarians.

Demographics	U.S. centenarians				χ²	Japanese centenarians				χ²
	LC(1)		LC(2)			LC(1)		LC(2)
	Freq.	%	Freq.	%		Freq.	%	Freq.	%
Gender					.12					.19
Men	19	16.7	21	18.4		18	19.6	38	21.8
Women	95	83.3	93	81.6		74	80.4	136	78.2
Ethnicity					.03
Whites	88	77.2	87	76.3		―	―	―	―
Blacks	26	22.8	27	23.7		―	―	―	―
Residential status					6.21*					1.44
Private home	48	42.5	54	47.4		61	66.3	126	72.4
Personal care Home	18	15.9	29	25.4		―	―	―	―
Long term care	47	41.6	31	27.2		25	27.2	36	20.7
Hospital	―	―	―	―		6	6.5	12	6.9
Education					9.60**					2.36
Lower high school	45	51.7	26	28.9		36	41.4	66	39.5
High school	21	24.1	32	35.6		39	44.8	65	38.9
College/post college	21	24.1	32	35.6		12	13.8	36	21.6
MMSE					7.28**					1.78
Poor cognitive health	60	52.6	39	34.8		61	70.9	98	62.4
High cognitive health	54	47.4				25	29.1	59	37.6

Abbreviation: LC = Latent Class.

Note. *p < .05; **p < .01; ***p< .001.

Table 4 also displays crosstabulation results for gender, residential status, education, and cognitive status differences in the two-class personality profiles solution for Japanese centenarians. No statistically significant demographic differences were found between the two personality profile groups. This may indicate that the two personality profile groups may differ in other domains that we did not test. In addition, when examining cultural differences in the two-class personality profiles, the crosstabulation analysis (not shown) suggested that the percentage of centenarians in each of the two-class personality profiles did not significantly differ across cultures, χ²(1, 494) =1.18, p = .278.

Discussion

This study had three main goals: first, to determine the personality profiles of centenarians; whether personality profiles were similar for the U.S. and Japanese centenarians; and later, to assess demographic differences between the personality profiles for the U.S. and Japanese centenarians.

This study identified personality profiles (classes) for U.S. and Japanese centenarians. Results from the LPA analyses revealed that a two-profile solution best described the personality structure of both samples. The two identified personality groups were significantly different. Results for the U.S. and Japanese centenarians indicate that Class 2, labeled the “resilient group,” is characterized by significantly lower scores on neuroticism and higher scores on extraversion, openness, agreeableness, and conscientiousness compared to U.S. and Japanese centenarians in Class 1.

The second group was Class 1, the nonresilient group, characterized as individuals who were rated as higher on neuroticism and lower on extraversion, openness, agreeableness, and conscientiousness (Costa & McCrae, 1992). Our results indicate that these two personality profile groups significantly differed on the five personality traits—indicating that U.S. and Japanese centenarians in the resilient group received significantly lower ratings on neuroticism and higher ratings on extraversion, openness, agreeableness, and conscientiousness when compared to U.S. and Japanese centenarians in the nonresilient group.

When comparing LPA results across the two cultures it is interesting to note that we found similar personality patterns. The results seem to support a common personality structure among centenarians from both countries and indicate that the resilient group was found in both studies—comprised of centenarians with high mean levels of extraversion, agreeableness, and conscientiousness, and low levels of neuroticism and openness. The two personality profiles significantly differed in personality configurations for the U.S. and the Japanese sample suggesting that the personality profiles of U.S. and Japanese centenarians from the resilient group significantly differ from personality profiles of centenarians in the nonresilient group.

The results suggest there are no significant cultural differences in the personality profiles of the U.S. and Japanese centenarians with a nonresilient group and a resilient group being found centenarians from the two countries. The lack of differences between U.S. and Japanese centenarians might be explained in terms of the unique population of study. Centenarians are survivors who have lived a long life due to their successful adaptation (Martin et al., 2010). The successful adaptation of centenarians is in part due to personal resources (i.e., personality). In order to live past 100 years of age, a “survivorship” personality profile may be beneficial (Martin et al., 2010). The similarities in personality profiles across U.S. and Japanese centenarians suggest that to survive past 100 years of age, specific personality profiles are associated with successful adaptation into the second century of life. One study (Vollrath & Torgersen, 2000) concluded the combination of low neuroticism and high conscientiousness was the most positive personality profile in terms of helping students manage stress and coping. Perhaps a resilient personality, in young and old age, has equipped the resilient group to persevere, survive, and enjoy positive outcomes in life.

One important issue aspect when conducting cross-cultural research is the possibility that other personality characteristics may be important for these groups. We used a well-established measure to assess personality traits in centenarians; the fact that we did find evidence supporting the existence of five NEO personality traits in each culture does not mean that other possible personality traits may exist within each culture. Studies should consider other approaches to understanding personality structure such as the six foci of personality approach (Hooker & McAdams, 2003) that include traits, states, personal action constructs (PACs), life story, self-narration, and self-regulation.

Results from the demographic mean comparisons between the two-personality profiles for U.S. centenarians suggest significant residential status, education, and mental status differences in the two-personality profiles. U.S. centenarians in the resilient group were more likely to live in private homes or personal care homes than in long-term care facilities, had attended high school or achieved higher academic degrees, and had higher mental status compared to U.S. centenarians from the nonresilient group; U.S. centenarians in the nonresilient group were more likely to live in long-term care facilities, had less education, and lower levels of mental status. These results seem to clearly differentiate the two personality profile groups; the resilient group appears to be better off in terms of some of the demographic characteristics. No demographic differences were found between the two-personality profile groups for the Japanese sample probably because the differences between the two groups may be due to other domains that were not tested. It is possible that other demographic variables not included in our analyses (e.g., family support, physical and functional health) would better distinguish between the two groups.

Hofstede and McCrae (2004) noted that at the individual level, personality dispositions reflect the makeup of the individual and the influence of the cultural context. Collectivist cultures like Japan are concerned with relationships shaping their behavior (Triandis, 2001). In addition, having a personality that “fits in” with the cultural context increases subjective well-being regardless of individual differences (Triandis, 2000). Chopik and Kitayama (2018) observed that Japanese individuals over the life span show greater decline in neuroticism and higher increase in conscientiousness in later life compared to Americans. Conscientiousness is defined as an individual’s tendency to follow socially prescribed norms and rules, the ability to delay personal gratification, maintain impulse control, and to respond in a consistent manner in certain situations (Roberts et al., 2009). Norms, duties, and obligations shape social behavior in collectivist cultures (Triandis, 1999). The two Japanese centenarian personality profile groups might not have had significant demographic differences due to the well-being of collectivist individuals depending on fitting in, maintaining good relationships, and following the norms of the culture (Triandis, 1999).

This study, like others, has several limitations. The results can only be generalized to a very old population; the findings may not apply to other age groups and may not be generalizable to all U.S. and Japanese centenarians or centenarians from other countries. Results for the U.S. sample represent personality profiles of centenarians living in Georgia, and results obtained for the Japanese sample may only represent the personality characteristics of centenarians from the Tokyo area. In addition, internal consistency for the personality dimension, Openness to new experience was relatively low for U.S. centenarians (alpha = .72) and Japanese centenarians (alpha = .61). Findings from this study represent the personality profiles of survivors who may differ from the personality characteristics from individuals who have already died. Specifically, the two personality profiles found in both samples may have influenced U.S. and Japanese centenarians’ longevity. Lastly, this study used proxy reports on centenarians’ personality traits, which may not accurately reflect their true personality characteristics. We may have found different personality profiles if centenarians’ self-reports were used to assess their personality. Future studies are needed to investigate the relationship between personality traits (profiles) and mortality.

Potential reasons for why centenarians with a nonresilient personality lived into the second century of life might be due to not experiencing many negative life events. In the case of centenarians, a significant number of centenarians have not experienced many negative life events and reported low negative emotions (Martin et al., 2010). In addition, centenarians have been observed to have a healthy aging phenotype with minimal chronic diseases (Willcox et al., 2008). As noted in the Georgia adaptation model, there are other factors contributing to longevity: family longevity, strong social and environmental support, adaptational skills, health behaviors and nutrition, as well as continued physical and mental health (Poon et al., 1992). Centenarians are unique survivors who have escaped challenges that would have compromised their longevity.

The most important finding from this study is that two similar personality profiles (i.e., the resilient and nonresilient groups) were found among long-lived older adults from a Western and an Eastern culture. A positive configuration of personality traits is not the only prerequisite for a long life; it is possible to be a centenarian with a nonresilient personality. Future studies should attempt to replicate our findings in other culturally diverse samples and investigate the link between personality profiles and important life outcomes such as mortality.

Footnotes

Acknowledgments

Additional authors include S. M. Jazwinski, R. C. Green, M. MacDonald, M. Gearing, W. R. Markesbery (deceased), J. L. Woodard, M. A. Johnson, J. S. Tenover, I. C. Siegler, W. L. Rodgers, D. B. Hausman, C. Rott, A. Davey, and J. Arnold. Authors acknowledge the valuable recruitment and data acquisition effort from M. Burgess, K. Grier, E. Jackson, E. McCarthy, K. Shaw, L. Strong and S. Reynolds, data acquisition team manager; S. Anderson, E. Cassidy, M. Janke, and J. Savla, data management; M. Poon for project fiscal management.

Authors’ Note

Grace D. da Rosa is now affiliated with Georgia State University, Atlanta, GA.

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The Georgia Centenarian Study (Leonard W. Poon, PI) was funded by 1P01AG17553 from the National Institute on Aging, a collaboration among The University of Georgia, Tulane University Health Sciences Center, Boston University, University of Kentucky, Emory University, Duke University, Wayne State University, Iowa State University, Temple University, and University of Michigan. The Tokyo Centenarian Study was supported in part by a grant from the Japanese Ministry of Health and Welfare for the Scientific Research Project on Longevity, a grant for studying the multidisciplinary approach to centenarians and its international comparison (Principal Investigator, Nobuyoshi Hirose); a grant from the Japanese Ministry of Education, Science and Culture (No.15730346); and aid for research from the Keio Health Consulting Center. This study is also supported by the International Joint Research Promotion Program of the Osaka University.

ORCID iD

Joseph Kim

Author Biographies

Grace da Rosa, PhD, is a lecturer at the Georgia State University, Gerontology Institute. Her research focuses on personality, mental health, life events, and cross-cultural issues.

Peter Martin, PhD, is university professor of Human Development and Family Studies at Iowa State University. His research is concerned with longevity, personality, stress, coping, and well-being of older adults.

Joseph Kim, is a PhD candidate in the Department of Human Development and Family Studies at Iowa State University. His research focuses on personality, multimorbidity, financial resources, and well-being.

Daniel Russell, PhD, is professor of Human Development and Family Studies at Iowa State University. His research interests are in social support, loneliness, and health, as well as in neighborhood effects on physical and mental health.

W. Todd Abraham, PhD, is assistant director of Data & Analytics in the Department of Human Development and Family Studies at Iowa State University. His special expertise is in advanced quantitative methods and statistics.

Yasuyuki Gondo, PhD, is professor in the College of Human Sciences at Osaka University. His research focuses on longevity, well-being, cognition, and personality among oldest-old adults.

Nobuyoshi Hirose, MD, is Emeritus professor in the Department of Geriatric Medicine at Keio University. His research is concerned with geriatric assessment, mild cognitive impairment, and extreme longevity.

Yukie Masui, PhD, is a research scientist at the Tokyo Metropolitan Institute of Gerontology. Her research interest focuses on personality and well-being of centenarians.

Leonard W. Poon, PhD, Dr. Phil, hc, is distinguished research professor Emeritus in Gerontology, Psychology, and Public Health, and director Emeritus of the Institute of Gerontology and the Georgia Geriatric Education Center at the University of Georgia. His primary research areas are in normal and pathological changes of cognition in aging and survival, longevity, and successful aging of the oldest old.

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