Biomedical subjects

Wenyaw Chan

Publications and source records attributed to Wenyaw Chan.

At least 19 recordsLinked to original sources

PubMed2006

Racial disparity and socioeconomic status in association with survival in older men with local/regional stage prostate carcinoma: findings from a large community-based cohort.

BACKGROUND: Few studies have examined the outcomes for Hispanic men with prostate carcinoma and incorporated socioeconomic factors in association with race/ethnicity in affecting survival, adjusting for factors on cancer stage, grade, comorbidity, and treatment. METHODS: We studied a population-based cohort of 61,228 men diagnosed with local or regional stage prostate carcinoma at age 65 years or older between 1992 and 1999 in the 11 SEER (Surveillance, Epidemiology, and End Results) areas, identified from the SEER-Medicare linked data with up to 11 years of followup. RESULTS: Low socioeconomic status was significantly associated with decreasing survival in all men with prostate carcinoma. Those living in the community with the lowest quartile of socioeconomic status were 31% more likely to die than those living in the highest quartile (hazard ratio [HR] of all-cause mortality: 1.31; 95% confidence interval [CI]: 1.25-1.36) after adjustment for patient age, comorbidity, Gleason score, and treatment. The HR remained almost unchanged after controlling for race/ethnicity (HR: 1.32; 95% CI: 1.26-1.38). Compared with Caucasians, the risk of mortality in African American men was marginally significantly higher (HR: 1.06; 95% CI: 1.01-1.11) after controlling for education, and no longer significant after adjusting for poverty, income, or composite socioeconomic variable; the HR was lower for Hispanic men (HR: 0.80; 95% CI: 0.72-0.89) after adjustment for education and other socioeconomic variables. CONCLUSION: Racial disparity in survival among men with local or regional prostate carcinoma was largely explained by socioeconomic status and other factors. Lower socioeconomic status appeared to be one of the major barriers to achieving comparable outcomes for men with prostate carcinoma.

Black or African American↗

PubMed2006

A meta-analytic approach for characterizing the within-worker and between-worker sources of variation in occupational exposure.

While many studies have quantified the sources of variation in exposure to workplace contaminants for individual groups of workers, patterns of exposure variability have not been investigated since a comprehensive evaluation was carried out over 10 years ago. Therefore, a systematic review of the literature was conducted to identify studies that applied the one-way random-effects model to describe exposure profiles of groups of workers classified on the basis of the kind of work performed and where it was performed. Quantitative estimates of the sources of variation in exposure along with information related to the workplace, contaminant and sampling strategy were compiled. For subsets of the data, based upon the classification scheme used to group workers, weighted empirical cumulative distribution functions were constructed and compared using the non-parametric Kolomogorov-Smirnov two-sample test. Further stratifications evaluated differences by industry, agent and characteristics of the sampling strategy. The review identified nearly 60 studies that examined the within-worker and between-worker sources of variation in exposure to workplace contaminants. In pooling results across studies, the between-worker variability increased as workers were aggregated across jobs and locations. The within-worker variability for an occupational group of workers was generally larger than the between-worker variability, although the differences in the variation in exposures across work shifts relative to the variation among workers' mean exposure levels diminished as groups were combined across jobs and locations. On average, gaseous exposures were more homogeneous than exposures to aerosols or dermal agents as were exposures in the chemical industry compared with the non-chemical industry. The design of sampling strategies also plays an important role with greater variability among groups of workers who were sampled randomly rather than systematically; in addition, differences were detected on the basis of the study period and sample size. In evaluating key features of the design and methods of the studies identified in the review, several methodological issues emerged given the heterogeneity in terms of how censored data were handled, which estimation method was applied and whether underlying assumptions of the models were met. Notwithstanding the utility of quantifying sources of variation in exposure, several challenges lie ahead with regard to ensuring quality in the collection, analysis and reporting of exposure monitoring data that would enhance efforts to accurately assess exposure.

Air Pollutants, Occupational↗

PubMed2006

Analysis of longitudinal multinomial outcome data.

Analysis of categorical outcomes in a longitudinal study has been an important statistical issue. Continuous outcome in a similar study design is commonly handled by the mixed effects model. The longitudinal binary or Poisson-like outcome analysis is often handled by the generalized estimation equation (GEE) method. Neither method is appropriate for analyzing a multinomial outcome in a longitudinal study, although the cross-sectional multinomial outcome is often analyzed by generalized linear models. One reason that these methods are not used is that the correlation structure of two multinomial variables can not be easily specified. In addition, methods that rely upon GEE or mixed effects models are unsuitable in instances when the focus of a longitudinal study is on the rate of moving from one category to another. In this research, a longitudinal model that has three categories in the outcome variable will be examined. A continuous-time Markov chain model will be used to examine the transition from one category to another. This model permits an unbalanced number of measurements collected on individuals and an uneven duration between pairs of consecutive measurements. In this study, the explicit expression for the transition probability is derived that provides an algebraic form of the likelihood function and hence allows the implementation of the maximum likelihood method. Using this approach, the instantaneous transition rate that is assumed to be a function of the linear combination of independent variables can be estimated. For a comparison between two groups, the odds ratios of occurrence at a particular category and their confidence intervals can be calculated. Empirical studies will be performed to compare the goodness of fit of the proposed method with other available methods. An example will also be used to demonstrate the application of this method.

Biometry↗

PubMed2006

Adding story-centered care to standard lifestyle intervention for people with Stage 1 hypertension.

This study examined the blood pressure (BP)-lowering effect of adding story-centered care (i.e., carefully attending to another's narrative) to standard lifestyle intervention (i.e., exercise training and nutrition counseling) for people with Stage 1 hypertension. The subjects (N = 24), who were university and hospital employees, were unmedicated and received standard lifestyle intervention; half were randomly assigned to story-centered care. Their 24-hour BP was measured four times at 8-week intervals, twice before and twice after the intervention. Subjects who received story-centered care had greater decreases (p < .05) in awake systolic BP over the 6-month study period. Neither systolic nor diastolic sleep BP was significantly affected. Story-centered care showed promise for contributing to the BP-lowering effect of lifestyle intervention. Approaches for integrating story-centered care into the treatment of people with hypertension are challenging but warrant further attention.

Adult↗

PubMed2006

Ethnic differences in symptoms of insomnia among adolescents.

SUBJECT OBJECTIVE: To provide data on the prevalence of symptoms of disturbed sleep, particularly insomnia, and to ascertain whether there are differentials attributable to ethnic culture or ethnic status. DESIGN: Data were collected from youths (aged 11-17 years) and adult caregivers from a community-based sample of households using personal interviews and questionnaires. SETTING: Managed-care subscriber populations in metropolitan area of over 4.5 million. PARTICIPANTS: The sample consisted of 4175 youths and their caregivers (35.4% European American, 35.4% African American, 20.5% Mexican American, and 8.7% Other American). INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: The overall prevalence of DSM-IV insomnia-like syndrome in the past month was 4.7%. Females were more likely to report this syndrome, as were lower-income youths. Prevalence for European American youths was 5.3%, 5.2% for African American, and 3.5% Mexican American youths (p > .05). There also were some ethnic differences across symptoms of sleep disturbance that constitute insomnia. CONCLUSION: For most comparisons, subsequent multivariate analyses indicate no significant ethnic difference, supporting the hypothesis that observed ethnic differences are due primarily to the effects of status differences (e.g., age, gender, socioeconomic status, etc.). Insomnia clearly is a major public health problem, with prevalences comparable to mood, anxiety and disruptive behavior disorders among adolescents.

Adolescent↗

PubMed2005

Variation in modes of chemotherapy administration for breast carcinoma and association with hospitalization for chemotherapy-related toxicity.

BACKGROUND: To the authors' knowledge, few studies to date have addressed the patterns of how chemotherapy was administered (administration modes) over time. In the current study, the goal of the authors was to describe how chemotherapy for breast carcinoma was administered and to determine whether chemotherapy administration modes were associated with toxicity in a community-based large cohort. METHODS: The authors studied 5256 women who were diagnosed with breast carcinoma at age 65 years or older between 1992-1999 and received chemotherapy. The patients were identified from the Surveillance, Epidemiology, and End Results (SEER)Program-Medicare linked databases. Chemotherapy drugs and modes of administration were determined through procedure codes in Medicare claims. RESULTS: Of the 5256 patients who received chemotherapy, 33% received it through an intravenous infusion for less than 1 hour; 39% through an intravenous infusion lasting 1-8 hours; 15% through an intravenous infusion lasting longer than 8 hours and requiring a pump; 12% through an intravenous push technique; and 1% through a subcutaneous, intramuscular, or intralesional injection. These modes varied substantially across the 11 SEER areas. The risks of hospitalization for chemotherapy-related toxicities (neutropenia, fever, thrombocytopenia, and adverse effects of systemic therapy) were not found to be significantly associated with different modes of chemotherapy after adjusting for other factors. Compared with patients receiving 5-flurouracil using an intravenous infusion for longer than 8 hours, the risk of toxicity was determined to be 0.96 (95% confidence interval [95% CI], 0.63-1.47) for patients treated with an intravenous infusion lasting 1-8 hours; 0.94 (95% CI, 0.62-1.41) for patients treated with an intravenous infusion lasting less than 1 hour; and 0.66 (95% CI, 0.38-1.08) for patients treated with subcutaneous, intramuscular, or intralesional injection or an intravenous push technique. CONCLUSIONS: There were substantial geographic variations noted in the modes of administering chemotherapy; however, these variations did not appear to be associated with the risk of toxicities (neutropenia, fever, thrombocytopenia, and adverse effects of systemic therapy).

Aged↗

PubMed2005

Changing patient characteristics and survival experience in an Alzheimer's center patient cohort.

BACKGROUND: Large and diverse dementia patient cohorts can further a variety of research programs aimed at improving diagnosis, treatment, and meaningful survival in AD. METHOD: We recruited 1,502 dementia patients between 1989 and 2002, subclassified using standardized criteria and laboratory procedures, and treated according to established guidelines. Baseline clinical and psychometric measures were repeated annually, in person or by use of a multi-modal telephone follow-up program that included many of the measures obtained at in-person visits. We tracked vital status of all subjects at 6-month intervals and offered autopsies to all participants. We assessed for cohort effects in baseline characteristics by 2-year intervals, examined the characteristics and outcomes for those who remained active compared to those who were eventually lost to follow-up, examined survival times for demographic or diagnostic subgroups, and assessed the accuracy of clinical diagnoses versus neuropathology. RESULTS: The average age at entry, average educational level, and baseline MMSE scores for subjects are increasing over time, and probable AD diagnoses are also increasing. Most (80.6%) subjects have remained active in our Center; those who did not were more likely to have a non-AD diagnosis. Survival averages 5.2 years (CI 4.98--5.37) and is influenced by age and gender, but not by diagnosis of probable versus possible AD. Our diagnostic accuracy is 89.6%, with high sensitivity to the presence of AD (96%). CONCLUSIONS: In a large and representative clinical cohort, the demographics of AD are changing over time. Careful analyses of those who continue and those who drop out from follow-up suggest that atypical diagnosis, rather than severity or demographic issues accounts for most of the attrition. Clinicians are likely to encounter increasingly older patients with milder disease, and these trends have implications for the design of clinical trials. Survival from the onset of first symptoms, similar for probable and possible AD cases, may be increasing over time.

Aged↗

PubMed2005

Determinants of the demand for breast cancer screening among women veterans in the United States.

Demand theory has been applied to use of breast exams for cancer prevention, but not since widespread promotion of mammography screening and managed care. Previous economic analyses may be biased due to inclusion of diagnostic exams and generally fail to consider perceived risk and time costs. The objective was to identify and measure the effect of economic, demographic, and behavioral factors that influence the use of mammography screening among US women veterans aged 50 years and older. Data are from a 2000-2001 national mail survey with telephone follow-up of a random sample of women veterans. There were a maximum of 3415 respondents aged 50 and over with no history of breast cancer. Maximum likelihood probit models were used to estimate the effects of the independent variables on the probability that a woman will have had a mammogram in the past year. Education, income, insurance, and perceived risk of breast cancer are directly related to use of mammography screening. Age, smoking, travel and waiting time are inversely related to the likelihood of mammography screening. Mammography use among women veterans is generally consistent with the theory of the demand for health and medical care, and also consistent with previous national studies on the demand for breast exams. Findings highlight the role of perceived risk and non-price barriers to mammography use in the context of widespread insurance coverage for mammography screening.

Aged↗

PubMed2004

Developmental, gender, and ethnic group differences in moods and ambulatory blood pressure in adolescents.

BACKGROUND: Adolescence is characterized by profound changes in physical, psychological, and social functioning thought to be accompanied by intense and varying moods. PURPOSE: Within a psychophysiological framework, this study examined the prevalence of 12 self-reported mood states of adolescents; investigated associations between specific mood states and ambulatory blood pressure readings; and explored effects of interactions among moods, gender, ethnic group, and maturation on ambulatory blood pressures. METHODS: The sample included 371 African American, European American, and Hispanic American adolescents 11 to 16 years old. Systolic (SBP) and diastolic (DBP) blood pressures were measured every 30 min with an ambulatory monitor and were synchronized with electronic activity monitoring and moods self-recorded during waking hours in a checklist diary. RESULTS: Moods differed significantly by gender, ethnic group, and maturation. Controlling for height, maturation, gender, ethnic group, mother's education, position, location, activity, other moods, and interactions of moods with other variables in a multilevel, random coefficients regression model, both positive and negative mood states were associated with higher levels of SBP and DBP; being relaxed or bored, or having a feeling of accomplishing things were associated with lower SBP and DBP. There were significant interaction effects of moods with physical maturity, gender, and ethnic group on ambulatory SBP and DBP. CONCLUSIONS: Further study of the modifying effects of gender, ethnic group, and stage of development on reports of moods, and their associations with cardiovascular responses is recommended.

Adolescent↗

PubMed2004

Sexual risk attitudes and intentions of youth aged 12-14 years: survey comparisons of parent-teen prevention and control groups.

In this study, the authors compared differences in sexual risk attitudes and intentions for three groups of youth (experimental program, n = 90; attention control, n = 80; and nonparticipant control, n = 634) aged 12-14 years. Two student groups participated with their parents in programs focused on strengthening family interaction and prevention of sexual risks, HIV, and adolescent pregnancy. Surveys assessed students' attitudes and intentions regarding early sexual and other health-risk behaviors, family interactions, and perceived parental disapproval of risk behaviors. The authors used general linear modeling to compare results. The experimental prevention program differentiated the total scores of the 3 groups (p < .05). A similar result was obtained for student intentions to avoid sex (p < .01). Pairwise comparisons showed the experimental program group scored higher than the nonparticipant group on total scores (p < .01) and on students' intention to avoid sex (p < .01). The results suggest this novel educational program involving both parents and students offers a promising approach to HIV and teen pregnancy prevention.

Adolescent↗

PubMed2003

Sustained benefit of a community and professional intervention to increase acute stroke therapy.

BACKGROUND: The ultimate test of an educational intervention is the sustainability of the effect after the intervention ceases. METHODS: The TLL Temple Foundation Stroke Project was a quasi-experimental study aimed at increasing Food and Drug Administration-approved acute stroke therapy in a nonurban community in east Texas. During the intensive community and professional intervention (phase 2), significantly more patients with acute stroke received intravenous tissue plasminogen activator (tPA) compared with the preintervention period (phase 1). In the comparison community, no change was noted. We present the results of tPA treatment in the 6 months after the intervention ended (phase 3). RESULTS: Two hundred thirty-eight patients had a validated stroke during phase 3. Among patients who experienced an ischemic stroke, 11.2% in the intervention group received intravenous tPA compared with 2.2% in phase 1 (P =.007). In the comparison group, 1.4% received intravenous tPA in phase 3 compared with 0.7% in phase 1 (P>.99). Among eligible candidates for treatment, 69.2% were treated in phase 3 in the intervention community compared with 13.6% in phase 1 (P =.002). In the comparison group, 20.0% were treated in phase 3 compared with 6.7% in phase 1 (P =.45). There was 1 protocol violation among the 9 patients treated in the intervention community in phase 3. CONCLUSIONS: There was a sustained benefit of the intervention in increasing tPA treatments in the intervention community even after cessation of the educational effort. Treatments in the control community remained few through all 3 phases of the study. A carefully planned multilevel intervention can improve community stroke treatments even in a nonurban community.

Drug Utilization↗

PubMed2003

Behavioral change for blood pressure control among urban and rural adults in Taiwan.

In exploring the mechanisms of behavioral change for hypertension control, a study based on the transtheoretical model was carried out in Taiwan in 2000, with a sample of 350 hypertensive adults living in Taipei urban and rural areas. The relationships among stages of change, processes of change, and demographic factors were analyzed for six health behaviors: low-fat food consumption, alcohol use, smoking, physical activity, weight control and routine blood pressure check-ups. The results showed that rural populations had greater difficulty than urban populations in avoiding smoking and engaging in physical activity, and the processes of change being used by urban populations were significantly greater than rural populations for diet, physical activity and routine blood pressure check-up. Individuals who use more processes of change will be more inclined to move from the pre-contemplation stage to the maintenance stage. Social liberation, self-reevaluation and counterconditioning were very important processes for changing diet behavior, engaging in physical activity and checking blood pressure on a regular basis.

Adult↗

PubMed2002

Sex and acute stroke presentation.

STUDY OBJECTIVES: We determine whether a sex difference exists for acute stroke emergency department presentation. METHODS: The TLL Temple Foundation Stroke Project is a prospective observational study of acute stroke management that identified 1,189 validated strokes in nonurban community EDs from February 1998 to March 2000. Structured interview of the patient and the person with the patient at symptom onset identified the symptom or symptoms that prompted the patient to seek medical attention. Interview data were available for 1,124 (94%) patients. A physician blinded to sex classified the reported symptoms into 14 categories. RESULTS: Nontraditional stroke symptoms were reported by 28% of women and 19% of men (odds ratio 1.62; 95% confidence interval 1.2 to 2.2). Nontraditional stroke symptoms, pain (men 8%, women 12%) and change in level of consciousness (men 12%, women 17%), were more often reported by women. Traditional stroke symptoms, imbalance (men 20%, women 15%) and hemiparesis (men 24%, women 19%), were reported more frequently by men. Trends were also found for women to present with nonneurologic symptoms (men 17%, women 21%) and men to present with gait abnormalities (men 11%, women 8%). There was no sex difference in the mean number of symptoms reported by an individual patient. CONCLUSION: This study suggests that a sex difference exists in reporting of acute stroke symptoms. Women with validated strokes present more frequently with nontraditional stroke symptoms than men. Recognition of this difference might yield faster evaluation and management of female patients with acute stroke eligible for acute therapies.

Aged↗

PubMed2002

Improving delivery of acute stroke therapy: The TLL Temple Foundation Stroke Project.

BACKGROUND AND PURPOSE: Only a small minority of acute stroke patients receive approved acute stroke therapy. We performed a community and professional behavioral intervention project to increase the proportion of stroke patients treated with approved acute stroke therapy. METHODS: This study used a quasi-experimental design. Intervention and comparison communities were compared at baseline and during educational intervention. The communities were based in 5 nonurban East Texas counties. The multilevel intervention worked with hospitals and community physicians while changing the stroke identification skills, outcome expectations, and social norms of community residents. The primary goal was to increase the proportion of patients treated with intravenous recombinant tissue plasminogen activator (rTPA) from 1% to 6% of all cerebrovascular events in the intervention community. RESULTS: We prospectively evaluated 1733 patients and validated 1189 cerebrovascular events. Intravenous rTPA treatment increased from 1.38% to 5.75% among all cerebrovascular event patients in the intervention community (P=0.01) compared with a change from 0.49% to 0.55% in the comparison community (P=1.00). Among the ischemic stroke patients, an increase from 2.21% to 8.65% was noted in the intervention community (P=0.02). The comparison group did not appreciably change (0.71% to 0.86%, P=1.00). Of eligible intravenous rTPA candidates, treatment increased in the intervention community from 14% to 52% (P=0.003) and was unchanged in the comparison community (7% to 6%, P=1.00). CONCLUSIONS: An aggressive, multilevel stroke educational intervention program can increase delivery of acute stroke therapy. This may have important public health implications for reducing disability on a national level.

Acute Disease↗

PubMed2002

Healthy Growth: project description and baseline findings.

OBJECTIVES: The purpose of the study was to describe the physical activity, blood pressure, and body fat patterns of sixth-grade, African-American girls (N = 82), who participated in the Healthy Growth Study. The purpose of the primary study questions was to determine which sets of variables best predict blood pressure, physical activity, and body fat. DESIGN AND METHODS: This paper is a cross sectional analysis of the first assessment of a 5-year longitudinal project. Standard procedures were used to assess height, weight, skinfolds, blood pressure, physical activity, predictors of physical activity, maturation, dietary intake, fitness level, and health behaviors. RESULTS: The average age of the subjects was 12.3 years; almost two-thirds of the girls had reached menarche. Fifty-two percent of the 13-year-olds had body mass index (BMI) values greater than the 85th percentile for their age and sex compared to 32% of the 12-year-olds. None of the variables were significantly related to diastolic or systolic blood pressure. Physical activity was significantly and negatively related to total percent of calories from fat and to breast stages and positively related to waist/thigh ratio. Body mass index (BMI) was significantly and positively related to breast stages. CONCLUSIONS: Important developmental differences between 12- and 1 3-year-olds were evident. Body mass index (BMI) was mainly dependent on physical maturity. No relationship was found between BMI and blood pressure. The relationship between physical activity and waist/thigh ratio merits further study. The importance of BMI and physical inactivity as potential indicators of cardiovascular risk in adolescent girls is discussed. Developmentally appropriate and culturally competent interventions are recommended to increase physical activity and healthy eating behaviors among adolescents.

Adolescent↗

PubMedDate not supplied

Is obesity associated with poor sleep quality in adolescents?

Obesity has reached epidemic proportions in the U.S. and more developed countries, particularly so among adolescents. A substantial impact on public health could be achieved if other factors causing obesity besides the conventional ones of diet and physical activity could be identified and acted upon. The present study investigates whether there is a link between low sleep quality and obesity in a tri-ethnic, cross-sectional sample (n = 383) of male and female adolescents ages 11-16 years old (Heartfelt Study). Sleep quality was expressed as two variables, total sleep time and sleep disturbance time obtained by 24-hour wrist actigraphy. Percent body fat and body mass index (BMI) were used together to define obesity. The potential influence of demographic and behavioral confounders were considered in models that described the relation of sleep to obesity occurrence. Obese adolescents experienced less sleep than nonobese adolescents (P < 0.01). For each hour of lost sleep, the odds of obesity increased by 80%. Sleep disturbance was not directly related to obesity in the sample, but influenced physical activity level (P < 0.01). Daytime physical activity diminished by 3% for every hour increase in sleep disturbance. The above observations were independent of potential confounding variables. Inadequate and poor sleep quality in adolescents may be important factors to consider in the prevention of childhood obesity.

Adolescent↗

PubMedDate not supplied

Utility of different body composition indicators: demographic influences and associations with blood pressures and heart rates in adolescents (Heartfelt Study).

PRIMARY OBJECTIVE: To compare the utility of 10 commonly used body composition indicators (BCIs) in relation to demographic characteristics and cardiovascular risk factors. RESEARCH DESIGN: A cross-sectional, school sample was studied. SUBJECTS: Three hundred and eighty-four Black, White and Hispanic adolescents 11-16 years of age from Houston, Texas, USA (Heartfelt Study) were studied. METHODS: BCIs include impedance and skinfold estimates of fat-free mass (FFM); fat mass (FM) and per cent body fat (PBF); resistance mass index (RMI); body mass index (BMI); and waist and abdomen circumferences. The cardiovascular risk factors (blood pressures/heart rates) are summarized by factor analysis. Sexual maturity was clinically assessed. RESULTS: Two distinct classes of BCIs emerged with respect to demographic influences: (1) RMI, impedance and skinfold estimators, for which sexual dimorphism is evident, and (2) BMI and circumferences, for which it is not. All BCIs were strongly related to general (systolic) blood pressure, but only body fat variables were related to heart rates. Skinfold-derived FM, PBF and mid-body circumferences were the variables most strongly related to cardiovascular risk factors. CONCLUSIONS: RMI, impedance or skinfold estimators are necessary for research requiring an accurate description of body composition changes during adolescence and for assessing the role of lean and fat tissue in disease aetiology. A 2-skinfold method is just as effective as the more complicated impedance. Mid-body circumferences are closely related to blood pressures and heart rates, suggesting their importance as indicators of abdominal fat in adolescents.

Adipose Tissue↗

PubMedDate not supplied

Anger in adolescents: sex, ethnicity, age differences, and psychometric properties.

BACKGROUND: The State-Trait Anger Expression Inventory (STAXI), a self-report questionnaire, is designed to measure the experience and expression of anger. Reliability and validity of the STAXI have been well established among African and European Americans aged 13 years and older. However, little is known of the use of this instrument among adolescents younger than 13 years and Hispanic American adolescents. OBJECTIVES: Objectives were (a) to test ethnic, sex, and age group differences in STAXI scores in a sample of 11-to-16-year-old African, Hispanic, and European American adolescents; and (b) to assess the psychometric properties of the STAXI among these same adolescents with special emphasis on Hispanic youths, for whom no data are available. METHODS: A cross-sectional design was used with stratified quota sampling techniques. Participants (N = 394) were African, Hispanic, and European Americans aged 11-16 years and were drawn from one public middle school and two public high schools in Houston, Texas. RESULTS: Internal consistency reliability for the anger scales (STAXI) ranged from 0.61 (anger-in) to 0.91 (state-anger) for the younger group (aged 11-13 years), and 0.68 (anger-in) to 0.88 (state-anger) for the older Hispanic Americans (aged 14-16). No notable differences were seen among the three ethnic groups in regards to internal consistency. Results of factor analyses of the five anger scales were similar to those reported originally by the scale author. Ethnicity and age had statistically significant main effects on the anger scales, and there was only one interaction. DISCUSSION: The use of the STAXI among a tri-ethnic adolescent population is warranted. The anger-in scale may be less reliable, especially among younger adolescents.

Adolescent↗