The utility of a non-verbal prospective memory measure as a sensitive marker for early-stage Alzheimer's disease in Hong Kong.

ABSTRACT Background: With the proportion of older adults in Hong Kong projected to double in size in the next 30 years, it is important to develop measures for detecting individuals in the earliest stage of Alzheimer's disease (AD, 0.5 in Clinical Dementia Rating, CDR). We tested the utility of a non-verbal prospective memory task (PM, ability to remember what one has to do when a specific event occurs in the future) as an early marker for AD in Hong Kong Chinese. Methods: A large community dwelling sample of older adults who are healthy controls (CDR 0, N = 125), in the earliest stage of AD (CDR 0.5, N = 125), or with mild AD (CDR 1, N = 30) participated in this study. Their reaction time/accuracy data were analyzed by mixed-factor analyses of variance to compare the performance of the three CDR groups. Logistic regression analyses were performed to test the discriminative power of these measures for CDR 0 versus 0.5 participants. Results: Prospective memory performance declined as a function of AD severity: CDR 0 > CDR 0.5 > CDR 1, suggesting the effects of early-stage AD and AD progression on PM. After partialling out the variance explained by psychometric measures (e.g., ADAS-Cog), reaction time/accuracy measures that reflected the PM still significantly discriminated between CDR 0 versus 0.5 participants in most of the cases. Conclusion: The effectiveness of PM measures in discriminating individuals in the earliest stage of AD from healthy older adults suggests that these measures should be further developed as tools for early-stage AD discrimination.

Effects of education on very mild dementia among Chinese people in Hong Kong: potential mediators in the Cantonese Mini-Mental State Examination tasks.

BACKGROUND: In Hong Kong, older Chinese adults generally have a low level of education. This study examined the effect of education on very mild Alzheimer's disease (AD), as quantified by Clinical Dementia Rating (CDR) scale (CDR 0.5 versus 0), in a Chinese community. The Cantonese version of the Mini-Mental State Examination (C-MMSE) was used to estimate cognitive abilities that were related to the level of education, and that in turn serve as protective factors for AD. METHODS: A total of 788 community-dwelling older adults (383 CDR 0 and 405 CDR 0.5) were recruited in this cross-sectional study, which was derived from a population-based prevalence project. The participants' number of years of education and C-MMSE scores were used to predict their CDR scores using logistic regression and the mediation effects of C-MMSE scores were analyzed. RESULTS: Consistent with previous studies, the chance of being rated as having very mild AD increased with age, but decreased with years of education, among the older adult community of Hong Kong. The effect of education on very mild dementia was weakened substantially when C-MMSE scores were included as mediating variables. CONCLUSIONS: The findings indicate that the protective effects of education on dementia were mediated by an enhancement of older adults' performance on some C-MMSE items, including attention and orientation to time and place.

The effect of diet and strength training on obese children's physical self-concept.

AIM: The aim of this study was to examine the effects of a 6-week diet and exercise program, with emphasis on strength training, on the physical self-concept, body composition, and physical fitness of young overweight and obese children. METHODS: Eighty-two overweight and obese children aged 8-11 years were randomized into a diet-only or a diet-and-strength training group. Self-concept, body composition and physical fitness were measured before and after the 6-week study period using the Physical Self Description Questionnaires (PSDQ), dual-energy X-ray absorptiometry (DXA), and standard fitness tests. Dietary intake was assessed with a food frequency questionnaire. Total daily energy intake was significantly reduced in both groups with a trend of more reduction in the diet-only group. RESULTS: Both groups developed greater confidence in strength. Those in the diet-and-strength training group also improved their endurance self-concept. Body Mass Index (BMI) decreased significantly in both groups. Lean mass increased significantly in both groups but significantly more in the diet-and-strength training group (+0.8 kg vs +0.3 kg, P<0.05). Handgrip, shuttle run, sit-up, and push-up were significantly improved in both groups, to a significantly greater extent in the diet-and-strength training group. CONCLUSION: These findings confirm the 6-week program of either diet-only or diet-and-strength training improved overweight/obese children's self-perception of muscular strength and body composition. With the diet-and-strength training program, self-concept in endurance also improved and the gain in lean body mass was more than double that of the diet only group.

Childhood obesity, gender, actual-ideal body image discrepancies, and physical self-concept in Hong Kong children: cultural differences in the value of moderation.

Childhood obesity is increasingly prevalent in Western and non-Western societies. The authors related multiple dimensions of physical self-concept to body composition for 763 Chinese children aged 8 to 15 and compared the results with Western research. Compared with Western research, gender differences favoring boys were generally much smaller for physical self-concept and body image. Objective and subjective indexes of body fat were negatively related to many components of physical self-concept, but--in contrast to Western research--were unrelated to global self-esteem and slightly positively related to health self-concept. In support of discrepancy theory, actual-ideal discrepancies in body image were related to physical self-concept. However, consistent with the Chinese cultural value of moderation, and in contrast to Western results, being too thin relative to personal ideals was almost as detrimental as being too fat. The results reflect stronger Chinese cultural values of moderation and acceptance of obesity than in Western culture and have implications for social and educational policy in China.

Self-perception of physical competences in preadolescent overweight Chinese children.

OBJECTIVE: To compare self-perceptions of physical competences in overweight and in normal weight preadolescent Chinese children. DESIGN: Cross-sectional study. SETTING: Three primary schools and a university hospital in Hong Kong. SUBJECTS: A total of 634 children, comprising 558 (462 normal weight, 96 overweight) aged 8-12 y randomly sampled from three primary schools, and 76 similar age overweight children recruited from the community for a diet and exercise intervention programme. MEASUREMENTS: Height, weight and percentage body fat were measured. Self-perceptions of physical competences were determined by Physical Self-Descriptive Questionnaire (PSDQ). Corresponding actual physical competences were measured by physical fitness tests. RESULTS: Overweight children perceived themselves to have significantly more body fat than normal weight children, with poorer appearance, sports competence, endurance, coordination, flexibility, overall physical self-concept and self-esteem, but to be no less healthy, no less physically active and no less strong. Overweight children performed less well than normal weight children in measures of endurance, coordination and flexibility but better in strength. Poor self-perception of physical competences appeared only partly related to deficiencies in actual physical competences. CONCLUSION: Overweight children have poorer self-perception of their physical competences but do not perceive themselves to be less strong, healthy or physically active than normal weight children. Exercise programmes for overweight children could be more effective if designed with the knowledge of these self-perceptions.

Longitudinal multilevel models of the big-fish-little-pond effect on academic self-concept: counterbalancing contrast and reflected-glory effects in Hong Kong schools.

Longitudinal multilevel path models (7,997 students, 44 high schools, 4 years) evaluated effects of school-average achievement and perceived school status on academic self-concept in Hong Kong, which has a collectivist culture with a highly achievement-segregated high school system. Consistent with a priori predictions based on the big-fish-little-pond effect (BFLPE), higher school-average achievements led to lower academic self-concepts (contrast effect), whereas higher perceived school status had a counterbalancing positive effect on self-concept (reflected-glory, assimilation effect). The negative BFLPE is the net effect of counterbalancing influences, stronger negative contrast effects, and weaker positive assimilation effects so that controlling perceived school status led to purer--and even more negative--contrast effects. Attending a school where school-average achievement is high simultaneously resulted in a more demanding basis of comparison for one's own accomplishments (the stronger negative contrast effect) and a source of pride (the weaker positive assimilation effect).

Suicide in Hong Kong 1971-1990: age trend, sex ratio, and method of suicide.

This study gives an overview of the suicide rates in Hong Kong in the last 2 decades (1971-1990). It was found that the average suicide rate for the whole population was 11.3 per 100,000 population and it has been quite steady in recent years. The male and female adolescent (age-group 10-24 years) suicide rates were approximately the same, while the ratio of the overall male to female rate was 1.3:1. This indicated a relatively high female rate as compared with other countries. An examination of the suicide rates for various age-groups showed that the rate increased with age. The adolescent suicide rate was not particularly high (4.7 per 100,000 population for the age-group 10-24 years), but that for the elderly was 4-5 times the overall rate (49.5 per 100,000 population for those aged over 70 years). As regards the method of suicide, jumping from a height and hanging predominated in all age-groups. These methods were in great contrast to those used in other countries.

Confirmatory factor analyses of seven locus of control measures.

Confirmatory factor analyses with congeneric models were used to examine whether seven common locus of control instruments were measuring the same single construct. The subjects were 191 adolescents, and the analyses were based on the intercorrelations among the scales as reported by Furnham (1987). In addition to the one-factor congeneric model, other first- and second-order factor models were posited to reflect the effects due to target subject (adult vs. child), dimensionality (uni- vs. multidimension), and scaling method (yes/no, forced-choice, 7-point). A recently developed strategy in multitrait-multimethod analyses was also adopted in the analyses. In general, results of this study did not substantiate the claim that all scales were measuring the same construct. Even among the more strongly correlated unidimensional measures for children, the support for a one-factor model was still rather weak. Furthermore, results did not justify the categorization of the measures by their target subject, dimensionality, and scaling method.

Moral development of chinese students in Hong Kong.

The Defining Issues Test (DIT) of moral judgment by Rest was administered to 242 Chinese secondary school and university students in Hong Kong. Metric unfolding analysis on the stage scores of different groups of both sexes and various educational levels revealed that the moral development of the Chinese students were in agreement with Kohlberg's major distinctions of preconventional, conventional and postconventional levels. The sequence of stage development within the same level (e.g., between stages 5 and 6), however, was sometimes ambiguous. Results also showed that older university students were morally more mature than the younger secondary school students in their P%, D, and stages 5 and 6 scores. The applicability of DIT in the Chinese culture and the universality of Kohlberg's 6-stage model were generally supported.

Development of the Multi-Trait Personality Inventory (MTPI): comparison among four Chinese populations.

Anemic approach was adopted to develop a culture-specific instrument for the assessment of Chinese personality. The Multi-Trial Personality Inventory (MTPI) was administered to 1,673 men and 944 women in four major Chinese populations. It was found that Chinese in mainland China, Taiwan, Hong Kong, and the United States possess some common traits deeply rooted in the Chinese culture characterized by Confucian thoughts (e.g., self-discipline and moderation) and some additional traits nurtured by their respective environments. Consequently, findings of this study lent support to the hypothesis that, in spite of superficial discontinuities, there are basic continuities in the personality traits of mainland and overseas Chinese. The cross-cultural differences in personality were examined from a political-social perspective and also explained with a cultural-ecological model. In the development of the MTPI, a new methodology that relies on forming factor-consistent clusters was employed to deal successfully with the problem of complex factor space.

Is More Ever Too Much? The Number of Indicators per Factor in Confirmatory Factor Analysis.

We evaluated whether "more is ever too much" for the number of indicators (p) per factor (p/f) in confirmatory factor analysis by varying sample size (N = 50-1000) and p/f (2-12 items per factor) in 35,000 Monte Carlo solutions. For all N's, solution behavior steadily improved (more proper solutions, more accurate parameter estimates, greater reliability) with increasing p/f. There was a compensatory relation between N and p/f: large p/f compensated for small N and large N compensated for small p/f, but large-N and large-p/f was best. A bias in the behavior of the χ(2) was also demonstrated where apparent goodness of fit declined with increasing p/f ratios even though approximating models were "true". Fit was similar for proper and improper solutions, as were parameter estimates form improper solutions not involving offending estimates. We also used the 12-p/f data to construct 2, 3, 4, or 6 parcels of items (e.g., two parcels of 6 items per factor, three parcels of 4 items per factor, etc.), but the 12-indicator (nonparceled) solutions were somewhat better behaved. At least for conditions in our simulation study, traditional "rules" implying fewer indicators should be used for smaller N may be inappropriate and researchers should consider using more indicators per factor that is evident in current practice.