Biomedical subjects

John P Elder

Publications and source records attributed to John P Elder.

At least 19 recordsLinked to original sources

PubMed2007

Acculturation and body image perception among Latino youth.

OBJECTIVES: Examine the prevalence and predictors of body image dissatisfaction and disordered eating among Latino youth. DESIGN: One hundred and sixty-seven Latino youth were surveyed as part of a tailored nutrition communication intervention. The youth's mean age was 12.81 years (SD = 2.74) and 54% were female. Mean self-rated health was 2.59 (SD = 1.02; range: 1 = good to 5 = poor), despite 70% reporting a desire to be thinner. Using age and gender-specific growth charts, 16% of the youth were classified as at risk for overweight and 34% were classified as overweight. RESULTS: Among adolescents, girls (p < or = 0.001), youth who were classified as at risk for or being overweight (p < or = 0.001), and who more strongly recognized and agreed with socially sanctioned standards of appearance as represented in the media (Standardized beta St. beta = 1.86, p < or = 0.001) were more dissatisfied with their body image (R(2) = 0.57). Among children, being at risk for or overweight (p < or = 0.001), reporting a stronger affiliation with the Mexican culture (St. beta = 0.84, p < or = 0.01) and stronger expectations that a healthy diet was associated with improved appearance (St. beta = 0.63, p < or = 0.05) predicted greater body image dissatisfaction (R(2) = 0.55). CONCLUSION: Interventions that address sociocultural attitudes toward appearance may be effective at reducing both the prevalence of body image dissatisfaction and disordered eating.

Acculturation↗

PubMed2007

Policies and opportunities for physical activity in middle school environments.

BACKGROUND: This study examined physical activity opportunities and barriers at 36 geographically diverse middle schools participating in the Trial of Activity for Adolescent Girls. METHODS: Principals, physical education and health education department heads, and program leaders were interviewed to assess policies and instructional practices that support physical activity. RESULTS: Schools provided approximately 110 hours per year in physical education instruction. Approximately 20% of students walked or bicycled to school. Eighty-three percent of schools offered interscholastic sports and 69% offered intramural sports. Most schools offered programs for girls, but on average, only 24 girls ( approximately 5%) in the schools attended any programs. Only 25% of schools allowed after school free play. An overall score created to assess school environmental support for physical activity indicated that, on average, schools met 6.7 items of 10 items. Free/reduced lunch program participation versus not (p = .04), perceived priority of physical education instruction over coaching (p = .02), and safety for walking/bicycling to school (p = .02) predicted environmental support score. CONCLUSIONS: Schools have policies and practices that support physical activity, although unfavorable practices exist. Schools must work with community partners and officials to provide environments that optimally support physical activity, especially schools that serve low-income students.

Adolescent↗

PubMed2006

Is parenting style related to children's healthy eating and physical activity in Latino families?

Parenting styles influence a child's risk for obesity. The goals of this study are to evaluate the influence of (i) parenting style on children's health behaviors (physical activity and dietary intake), (ii) children's sociodemographic characteristics on parenting style and on children's health behaviors and (iii) parents' sociodemographic characteristics on their use of controlling styles to promote a healthy home environment. Survey and anthropometric data were collected from a community sample of Latino parents (n = 812) and their children in kindergarten through second grade. Parental use of positive reinforcement and monitoring was associated with children's healthy eating and exercise. Also, parents' use of appropriate disciplining styles was associated with healthier eating, while parental use of control styles was associated with unhealthy eating. The daughters of parents who used controlling styles ate more unhealthy foods than did the sons. Older, employed and more acculturated parents used less controlling styles than their counterparts. Parenting interventions targeting children's dietary intake and physical activity should encourage parents to use more positive reinforcement and monitor their children's health behaviors as these parenting styles are associated with healthier behaviors. Moreover, intervention researchers may want to encourage Latino parents to use less controlling styles with girls as this parenting style increased girls' risk for unhealthy eating.

Adult↗

PubMed2006

Girls' perception of physical environmental factors and transportation: reliability and association with physical activity and active transport to school.

BACKGROUND: Preliminary evidence suggests that the physical environment and transportation are associated with youth physical activity levels. Only a few studies have examined the association of physical environmental factors on walking and bicycling to school. Therefore, the purpose of this study was (1) to examine the test-retest reliability of a survey designed for youth to assess perceptions of physical environmental factors (e.g. safety, aesthetics, facilities near the home) and transportation, and (2) to describe the associations of these perceptions with both physical activity and active transport to school. METHODS: Test and retest surveys, administered a median of 12 days later, were conducted with 480 sixth- and eighth-grade girls in or near six U.S. communities. The instrument consisted of 24 questions on safety and aesthetics of the perceived environment and transportation and related facilities. Additionally, girls were asked if they were aware of 14 different recreational facilities offering structured and unstructured activities, and if so, whether they would visit these facilities and the ease with which they could access them. Test-retest reliability was determined using kappa coefficients, overall and separately by grade. Associations with physical activity and active transport to school were examined using mixed model logistic regression (n = 610), adjusting for grade, race/ethnicity, and site. RESULTS: Item-specific reliabilities for questions assessing perceived safety and aesthetics of the neighborhood ranged from 0.31 to 0.52. Reliabilities of items assessing awareness of and interest in going to the 14 recreational facilities ranged from 0.47 to 0.64. Reliabilities of items assessing transportation ranged from 0.34 to 0.58. Some items on girls' perceptions of perceived safety, aesthetics of the environment, facilities, and transportation were important correlates of physical activity and, in some cases, active transport to school. CONCLUSION: This study provides some psychometric support for the use of the questionnaire on physical environmental factors and transportation for studying physical activity and active transport to school among adolescent girls. Further work can continue to improve reliability of these self-report items and examine their association of these factors with objectively measured physical activity.

Journal Article↗

PubMed2006

The relationship between unsupervised time after school and physical activity in adolescent girls.

BACKGROUND: Rising obesity and declining physical activity levels are of great concern because of the associated health risks. Many children are left unsupervised after the school day ends, but little is known about the association between unsupervised time and physical activity levels. This paper seeks to determine whether adolescent girls who are without adult supervision after school are more or less active than their peers who have a caregiver at home. METHODS: A random sample of girls from 36 middle schools at 6 field sites across the U.S. was selected during the fall of the 2002-2003 school year to participate in the baseline measurement activities of the Trial of Activity for Adolescent Girls (TAAG). Information was collected using six-day objectively measured physical activity, self-reported physical activity using a three-day recall, and socioeconomic and psychosocial measures. Complete information was available for 1422 out of a total of 1596 respondents.Categorical variables were analyzed using chi square and continuous variables were analyzed by t-tests. The four categories of time alone were compared using a mixed linear model controlling for clustering effects by study center. RESULTS: Girls who spent more time after school (> or = 2 hours per day, > or = 2 days per week) without adult supervision were more active than those with adult supervision (p = 0.01). Girls alone for > or = 2 hours after school, > or = 2 days a week, on average accrue 7.55 minutes more moderate to vigorous physical activity (MVPA) per day than do girls who are supervised (95% confidence interval ([C.I]). These results adjusted for ethnicity, parent's education, participation in the free/reduced lunch program, neighborhood resources, or available transportation. Unsupervised girls (n = 279) did less homework (53.1% vs. 63.3%), spent less time riding in a car or bus (48.0% vs. 56.6%), talked on the phone more (35.5% vs. 21.1%), and watched more television (59.9% vs. 52.6%) than supervised girls (n = 569). However, unsupervised girls also were more likely to be dancing (14.0% vs. 9.3%) and listening to music (20.8% vs. 12.0%) (p < .05). CONCLUSION: Girls in an unsupervised environment engaged in fewer structured activities and did not immediately do their homework, but they were more likely to be physically active than supervised girls. These results may have implications for parents, school, and community agencies as to how to structure activities in order to encourage teenage girls to be more physically active.

Journal Article↗

PubMed2006

A description of the social-ecological framework used in the trial of activity for adolescent girls (TAAG).

Social-ecological (SE) models are becoming more widely used in health behavior research. Applying SE models to the design of interventions is challenging because models must be tailor-made for each behavior and population, other theories need to be integrated into multi-level frameworks, and empirical research to guide model development is limited. The purpose of the present paper is to describe a SE framework that guided the intervention and measurement plans for a specific study. The trial of activity for adolescent girls (TAAG) is a multi-center study of interventions to reduce the decline of physical activity in adolescent girls. The TAAG framework incorporates operant learning theory, social cognitive theory, organizational change theory and the diffusion of innovation model in a multi-level model. The explicit and practical model developed for TAAG has already benefited the study and may have elements that can generalize to other health promotion studies.

Adolescent↗

PubMed2006

Long-term effects of a communication intervention for Spanish-dominant Latinas.

BACKGROUND: Few studies compare the influence of different types of dietary interventions on the dietary practices of Latinas in the short and long term. The present study examined the 1-year impact of two innovative behavior-change approaches to reduce dietary fat and increase fiber. DESIGN: Three-group randomized controlled trial: (1) personalized dietary counseling via lay heath advisors (promotoras) plus tailored print materials delivered via the mail, (2) tailored mailed print materials only, and (3) targeted mailed "off-the-shelf" materials. SETTING/PARTICIPANTS: A total of 357 Latinas were randomly assigned to the three aforementioned conditions. INTERVENTION: Promotora and tailored print materials. MAIN OUTCOME MEASURES: Fat intake (total grams of fat and percent calories from dietary fat) and number of grams of dietary fiber. RESULTS: Earlier work reported that at immediate post-intervention the promotora group achieved significantly lower levels of total fat grams, and lower levels of energy intake, total saturated fat, total carbohydrates, glucose, and fructose than the targeted group. However, the present longitudinal analyses suggest that the effects achieved by the promotoras dissipated over the 12-month follow-up period while the effects of the tailored group concurrently improved. CONCLUSIONS: The high interactivity (i.e., calls, visits) of the promotora condition may have been the most salient reinforcer and may have led to further tailoring, making this type of intervention more effective than the comparison groups in the short term. Further research should explore whether booster sessions involving promotoras help to maintain the impact over time.

Adult↗

PubMed2006

A demonstration of modeling count data with an application to physical activity.

Counting outcomes such as days of physical activity or servings of fruits and vegetables often have distributions that are highly skewed toward the right with a preponderance of zeros, posing analytical challenges. This paper demonstrates how such outcomes may be analyzed with several modifications to Poisson regression. Five regression models 1) Poisson, 2) overdispersed Poisson, 3) negative binomial, 4) zero-inflated Poisson (ZIP), and 5) zero-inflated negative binomial (ZINB) are fitted to data assessing predictors of vigorous physical activity (VPA) among Latina women. The models are described, and analytical and graphical approaches are discussed to aid in model selection. Poisson regression provided a poor fit where 82% of the subjects reported no days of VPA. The fit improved considerably with the negative binomial and ZIP models. There was little difference in fit between the ZIP and ZINB models. Overall, the ZIP model fit best. No days of VPA were associated with poorer self-reported health and less assimilation to Anglo culture, and marginally associated with increasing BMI. The intensity portion of the model suggested that increasing days of VPA were associated with more education, and marginally associated with increasing age. These underutilized models provide useful approaches for handling counting outcomes.

Journal Article↗

PubMed2006

Association of a traditional vs shared meal decision-making and preparation style with eating behavior of Hispanic women in San Diego County.

OBJECTIVE: To examine the influence of meal decision-making and preparation on Hispanic women's dietary practices. DESIGN: One-on-one structured interviews were conducted, assessing meal decision-making and preparation practices, barriers, and behavioral strategies to eating low-fat and high-fiber diets, fat and fiber intake, demographic, and other psychosocial factors. SUBJECTS/SETTING: The study population included 357 Hispanic women living in the southern or central regions of San Diego County. Participants were recruited via random-digit dialing to a tailored nutrition communication intervention. MAIN OUTCOME MEASURE: Household decision-making style (alone vs with family) by household activity (decides meals, prepares meals, and decides snacks). STATISTICAL ANALYSES PERFORMED: Multiple logistic regressions were used to evaluate associations between the predictors and dependent variable. All models included adjustments for potential confounders, such as marital status, education, employment, age, and acculturation. RESULTS: A positive statistical association between Hispanic women's acculturation level and shared decision-making style was found. Also, Hispanic women in shared decision-making households faced greater psychosocial barriers to healthful eating and reported less healthful eating compared with Hispanic women in traditional households. Women in shared decision-making households were more likely to eat at fast-food restaurants, less likely to engage in behavioral strategies promoting fiber consumption, eat more saturated fat, and encounter more barriers to reduce dietary fat as compared with Hispanic women in traditional households. Acculturation did not attenuate differences in psychosocial and dietary practices between shared decision-making and traditional households. CONCLUSIONS: Study findings suggest intervention efforts should focus on different aspects of healthful eating among Hispanic women in shared-decision, compared with traditional, households.

Acculturation↗

PubMed2006

A typology of middle school girls: audience segmentation related to physical activity.

The Trial of Activity for Adolescent Girls (TAAG) combines social ecological and social marketing approaches to promote girls' participation in physical activity programs implemented at 18 middle schools throughout the United States. Key to the TAAG approach is targeting materials to a variety of audience segments. TAAG segments are individuals who share one or more common characteristic that is expected to correlate with physical activity. Thirteen focus groups with seventh and eighth grade girls were conducted to identify and characterize segments. Potential messages and channels of communication were discussed for each segment. Based on participant responses, six primary segments were identified: athletic, preppy, quiet, rebel, smart, and tough. The focus group information was used to develop targeted promotional tools to appeal to a diversity of girls. Using audience segmentation for targeting persuasive communication is potentially useful for intervention programs but may be sensitive; therefore, ethical issues must be critically examined.

Adolescent↗

PubMed2006

Girls' activity levels and lesson contexts in middle school PE: TAAG baseline.

PURPOSE: To assess girls' physical activity (PA) in middle school physical education (PE) as it relates to field site, lesson context and location, teacher gender, and class composition. METHODS: We observed girls' PA levels, lesson contexts, and activity promotion by teachers in 431 lessons in 36 schools from six field sites participating in the Trial of Activity for Adolescent Girls. Interobserver reliabilities exceeded 90% for all three categories. Data were analyzed using mixed-model ANOVA with controls for clustering effects by field site and school. RESULTS: Mean lesson length was 37.3 (+/-9.4) min. Time (13.9+/-7.0 min) and proportion of lessons (37.9+/-18.5%) spent in moderate to vigorous PA (MVPA), and time (4.8+/-4.2 min) and proportion of lessons (13.1+/-11.7%) in vigorous PA (VPA) differed by field site (P<0.004). Lesson time for instructional contexts differed by field site, with overall proportions as follows: game play (27.3%), management (26.1%), fitness activities (19.7%), skill drills (12.1%), knowledge (10.6%), and free play (4.4%). Coed classes were 7.9 min longer than girls-only classes (P=0.03). Although 27 s shorter, outdoor lessons were more intense (MVPA%=45.7 vs 33.7% of lesson, P<0.001) and provided 4.0 more MVPA minutes (P<0.001). MVPA, VPA, and lesson contexts did not differ by teacher gender. There was little direct promotion of PA by teachers during lessons. CONCLUSIONS: Substantial variation in the conduct of PE exists. Proportion of lesson time girls spent accruing MVPA (i.e., 37.9%) fell short of the Healthy People 2010 objective of 50%. Numerous possibilities exist for improving girls' PA in PE.

Adolescent↗

PubMed2005

Acculturation, parent-child acculturation differential, and chronic disease risk factors in a Mexican-American population.

Acculturation is typically defined in terms of individual responses to a dominant culture. In the present study, we examined the effects of different levels of acculturation among family members. Specifically, we looked at the health and risk behavior in Mexican-American children as related to a variety of psychosocial predictors, especially the differences in orientation toward Mexican- and Anglo-American cultures between them and their parents. Mother and child pairs (n = 106) noted their orientation toward both Anglo and Mexican cultures. Children's dietary and sedentary behaviors, tobacco and alcohol use (and susceptibility to use), and depressive symptoms were also measured. Males were more likely to be sedentary and consume higher levels of total fat and saturated fat, whereas girls reported higher levels of depression. Anglo-oriented youth consumed lower levels of calories from fat but also more alcohol than did their Mexican-oriented counterparts. The latter was particularly the case among those children who were relatively more Anglo oriented than were their parents. Parent-child acculturation differential in terms of the differences in Mexican orientation, in comparison, predicted susceptibility to tobacco use. However, the sum of the absolute values of these two differences predicted only lifetime alcohol use, and in a counter-intuitive direction. This familial measure of acculturation shows some promise, but additional formative research is needed to operationalize this construct.

Acculturation↗

PubMed2005

Ethnoracial differences among outdoor workers in key sun-safety behaviors.

BACKGROUND: Few sun-safety studies have included ethnoracially diverse groups. Comparison across such groups of sun-safety behaviors was the main objective of this analysis. METHODS: Postal workers (n =2543) self-reported frequency of sunscreen, wide-brim hat, and sunglasses use during the last 5 workdays on 5-point Likert-type scales ranging from "never" to "always." Responses were dichotomized by "always" versus all other responses. Generalized estimating equations were used to assess the association between ethnicity/race and frequency of each sun safety behavior. The baseline data reported in this paper were collected in the summer of 2001, and the randomized trial was completed in the summer of 2004. RESULTS: Ethnicity/race was significantly related to sunscreen and sunglasses use. For both sunscreen and sunglasses, the white group had significantly higher "always" rates than the other four groups (30% vs 14% to 23% and 63% vs 44% to 52%, respectively). CONCLUSIONS: The results of this study indicated that although non-Latino white employees tended to have higher rates of sun-safety behaviors, the rates of adequate protection of all groups were low.

Female↗

PubMed2005

Design of the Trial of Activity in Adolescent Girls (TAAG).

The primary aim of the Trial of Activity in Adolescent Girls (TAAG) is to test an intervention to reduce by half the age-related decline in moderate to vigorous physical activity (MVPA) in middle school girls. The intervention will be evaluated using a group-randomized trial involving 36 middle schools. The primary endpoint is the mean difference in intensity-weighted minutes (i.e., MET-minutes) of MVPA between intervention and comparison schools assessed using accelerometry. The TAAG study design calls for two cross-sectional samples, one drawn from 6th graders at the beginning of the study and the second drawn from 8th graders at the end of the study following the 2-year implementation of the intervention. An important strength of this design over a cohort design is the consistency with the goals of TAAG, which focus on environmental-level rather than individual-level interventions to produce change. The study design specifies a recruitment rate of 80% and a smaller sample of girls at baseline (n=48 per school) than at follow-up (n=96 per school). A two-stage model will be used to test the primary hypothesis. In the first stage, MET-weighted minutes of MVPA will be regressed on school, time (baseline or follow-up), their interaction, ethnicity and week of data collection. The second stage analysis will be conducted on the 72 adjusted means from the first stage. In the main-effects model, we will regress the follow-up school mean MET-weighted minutes of MVPA on study condition, adjusting for the baseline school mean. The TAAG study addresses an important health behavior, and also advances the field of group-randomized trials through the use of a study design and analysis plan tailored to serve the main study hypothesis.

Adolescent↗

PubMed2005

Restaurant and food shopping selections among Latino women in Southern California.

OBJECTIVE: This study describes and examines determinants of restaurant and food store selections in a sample of Latino women. DESIGN: Data were collected at the baseline home-based interview from women involved in a randomized community trial to improve dietary behaviors. The interview consisted of both a structured interview and the measurements of height, weight, and waist-to-hip ratio. SUBJECTS/SETTING: Participants included 357 Latino women recruited via random-digit dial in the Southern and Central areas of San Diego County, California. Women were included if they were between 18 and 67 years of age, not currently pregnant, and Spanish-language dominant; women were excluded if a family member was on a special diet or was planning to leave the area during the study. STATISTICAL ANALYSES PERFORMED: Means and frequencies were used to describe preference for various types of restaurants and food stores based on the North American Industry Classification System (NAICS). Independent samples t tests examined differences in levels of importance for preferring fast-food vs other restaurants and supermarkets/produce markets vs other grocery stores. Logistic regression models examined correlates of preferring fast-food restaurants vs all other restaurants and preferring supermarkets/produce markets vs all other grocery stores. RESULTS: More women reported eating at fast-food restaurants, followed by full-service restaurants and cafeterias. Younger women, employed women, women living in higher income households, and women living in the United States for a greater number of years preferred fast food. Supermarkets; grocery stores; and discount, bulk-purchase stores were equally represented as the primary food store. Women who lived in smaller households, had a smaller measured body mass, were married, and were more acculturated to the Anglo culture were more likely to shop at supermarkets compared with women who shopped at other grocery stores. CONCLUSIONS: Our findings suggest specific recommendations for targeting dietary interventions for the growing Latino population that take into account differences in levels of acculturation. For example, young Latino women who more closely identify with the Anglo culture and/or who report living in the United States for a longer period of time may benefit from targeted information on healthy restaurant behavior. On the other hand, traditional Latino women may benefit from instrumental support interventions such as tours to large supermarkets.

Acculturation↗

PubMed2005

Interpersonal and print nutrition communication for a Spanish-dominant Latino population: Secretos de la Buena Vida.

Participants (N=357) were randomly assigned to 1 of 3 conditions: lay health advisor (promotora) plus tailored print materials, tailored print materials only (tailored), or off-the-shelf print materials (control). The primary outcomes were calories from fat and daily grams of fiber. Secondary outcomes included total energy intake, total and saturated fat intake, and total carbohydrates. Adjusted for baseline values, calories from fat were 29%, 30%, and 30% for the promotora, tailored, and control conditions, respectively, and grams of fiber consumed were 16 g, 17 g, and 16 g. Significant Condition X Time interactions were not observed between baseline and 12-weeks postintervention. The LHA condition achieved significantly lower levels of energy intake, total fat and saturated fat, and total carbohydrates. The relative superiority of the promotora condition may derive from the personal touch achieved in the face-to-face interactions or from the women's use of print materials under the promotora's guidance.

Acculturation↗

PubMed2004

Validating outdoor workers' self-report of sun protection.

BACKGROUND: Few studies assessing sun safety behaviors have used validated survey instruments. Using an observational strategy, this study measured the validity of self-report of occupational sun protection behaviors. METHODS: Postal workers (N = 1,036) self-reported their frequency of protective clothing and sunglasses use during the past 5 workdays on Likert scales ranging from "Never" to "Always". Responses were dichotomized by Always vs. all other responses. Data collectors observed these same behaviors during mail delivery several days before survey administration. Agreement between the two measures was computed. RESULTS: Self-report for all items was significantly related to observed behaviors, with Kappa values in the good to excellent range (Kappas = 0.51-0.83). CONCLUSIONS: For outdoor postal workers, survey items assessing recent occupational use of sun-protective items had high levels of validity.

Adult↗

PubMed2004

Use of newsletters to promote environmental political action: an experimental analysis.

The managers of beach businesses were randomly assigned to receive no intervention or two newsletters per week for 6 weeks that presented economic consequences of damage to coastal water quality and how to contact politicians. The percentage of proenvironmental political contacts was significantly greater in the experimental (newsletter) group than in the control group. Logistical regression showed that contacts in the newsletter group were more than five times that of controls after adjusting for history of contacts and predisposition to take such action. Results suggest that the intervention can promote political action that could influence environmental policies and human health.

Conservation of Natural Resources↗