Biomedical subjects

S H Kelder

Publications and source records attributed to S H Kelder.

At least 19 recordsLinked to original sources

PubMed2001

Nicotine dependence, withdrawal symptoms, and adolescents' readiness to quit smoking.

The purpose of this study was to characterize nicotine dependence and nicotine withdrawal symptoms among adolescent smokers and to investigate associations between these key factors and adolescents' readiness to quit smoking. A total of 5624 high school students participated in a school-based survey. Of 1111 adolescents who were current or former smokers, the following stage-of-change distribution for smoking cessation was observed: precontemplation, 52.5%; contemplation, 16.0%; preparation, 7.5%; action, 13.2%; and maintenance, 10.8%. Among current smokers, 18.1% were substantially dependent on nicotine, 45.2% had moderate dependence, and 36.7% had no dependence. Higher proportions of current smokers than successful quitters reported withdrawal symptoms with their most recent quit attempts. Precontemplators exhibited significantly higher mean nicotine dependence scores than did students in the contemplation or preparation stages (F(2,837) = 12.03; p < 0.0001). A similar trend was observed for withdrawal-symptom scores across the stages of change. The nicotine dependence and withdrawal-symptom scores were significantly correlated (r = 0.44, p < 0.001). Nicotine dependence and nicotine withdrawal appear to interfere with adolescents' abilities and readiness to quit smoking, suggesting a potential role for nicotine replacement therapy in the treatment of tobacco use and dependence among adolescents.

Adolescent↗

PubMed2001

Dissemination and adoption of the Child and Adolescent Trial for Cardiovascular Health (CATCH): a case study in Texas.

The total impact of a health promotion program can be measured by the efficacy of the intervention multiplied by the extent of its implementation across the target population. The Child and Adolescent Trial for Cardiovascular Health (CATCH) was a school-based health promotion project designed to decrease fat, saturated fat, and sodium in children's diets, increase physical activity, and prevent tobacco use. This article describes the dissemination of CATCH in Texas, including the theoretical framework, strategies used, and lessons learned. To date (Fall 2000), CATCH materials have been adopted by more than 728 elementary schools in Texas.

Adolescent↗

PubMed2001

Depression and substance use in minority middle-school students.

OBJECTIVES: This study investigated the association between depression and substance use in a sample of middle-school students. METHODS: The 5721 students (59%-63% Hispanic) completed self-report items on depressive symptoms, recent smoking and binge drinking, and lifetime use of marijuana, cocaine, and inhalants. RESULTS: Symptoms of depression were strongly and positively related to substance use. For every type of use, a stepwise increase was seen between the percentage of students with low symptom frequency and the percentage of students with more symptoms. A sizable number of users reported symptoms indicating major depression. Depression scores showed few clinically meaningful differences among demographic subgroups. Substance use scores, in contrast, showed meaningful intergroup differences for racial/ethnic group and other demographic variables. CONCLUSIONS: Depressive symptoms and substance use were associated in a sample of middle-school students who were largely non-White and predominantly Hispanic. Greater understanding of the nature of this association is needed; this understanding should be used to design prevention programs, and prevention programs should be introduced at least in the middle-school years.

Achievement↗

PubMed2000

Prevalence and impact of dysmenorrhea on Hispanic female adolescents.

BACKGROUND: Dysmenorrhea is the leading cause of short-term school absenteeism. It is associated with a negative impact on social, academic, and sports activities of many female adolescents. Dysmenorrhea has not previously been described among Hispanic adolescents, the fastest growing minority group in the United States. OBJECTIVE: To determine the prevalence of dysmenorrhea among Hispanic female adolescents; its impact on academic performance, school attendance, and sports and social activities; and its management. PARTICIPANTS AND METHODS: A total of 706 Hispanic female adolescents, in grades 9 through 12, completed a 31-item questionnaire about the presence, duration, severity, treatment, and limitations of dysmenorrhea at a local urban high school. RESULTS: Among participants who had had a period in the previous 3 months, 85% reported dysmenorrhea. Of these, 38% reported missing school due to dysmenorrhea during the 3 months prior to the survey and 33% reported missing individual classes. Activities affected by dysmenorrhea included class concentration (59%), sports (51%), class participation (50%), socialization (46%), homework (35%), test-taking skills (36%), and grades (29%). Treatments taken for dysmenorrhea included rest (58%), medications (52%), heating pad (26%), tea (20%), exercise (15%), and herbs (7%). Fourteen percent consulted a physician and 49% saw a school nurse for help with their symptoms. Menstrual pain was significantly associated with school absenteeism and decreased academic performance, sports participation, and socialization with peers (P<.01). CONCLUSIONS: Dysmenorrhea is highly prevalent among Hispanic adolescents and is related to school absenteeism and limitations on social, academic, and sports activities. Given that most adolescents do not seek medical advice for dysmenorrhea, health care providers should screen routinely for dysmenorrhea and offer treatment. As dysmenorrhea reportedly affects school performance and attendance, school administrators may have a vested interest in providing health education on this topic to their students. Arch Pediatr Adolesc Med. 2000;154:1226-1229.

Absenteeism↗

PubMed2000

Planning and initiation of the ONDCP National Youth Anti-Drug Media Campaign.

An alarming upsurge in substance use among American youth in the past decade prompted the Office of National Drug Control Policy (ONDCP) to organize the multifaceted, primary prevention National Youth Anti-Drug Media Campaign. The campaign focuses on adolescents (especially ages 11-13 years), but also targets adolescents' parents and other influential adults. The campaign's main goal is to educate and enable American youth to reject illegal drugs. The purpose of this article is to describe the origin of campaign objectives, processes for the development of specific advertising messages to fulfill these objectives, and how the ONDCP experience could provide a model for other health-oriented media campaigns.

Adolescent↗

PubMed1999

Padres Trabajando por la Paz: a randomized trial of a parent education intervention to prevent violence among middle school children.

This paper reports the results of a randomized trial to test the effectiveness of a theoretically derived intervention designed to increase parental monitoring among Hispanic parents of middle school students. Role model story newsletters developed through the process of Intervention Mapping were mailed to half of a subsample of parents whose children participated in Students for Peace, a comprehensive violence prevention program. The results indicated that parents in the experimental condition (N = 38) who had lower social norms for monitoring at baseline reported higher norms after the intervention than the parents in the control condition (N = 39) (P = 0.009). Children of parents in the experimental group reported slightly higher levels of monitoring at follow-up across baseline values, whereas control children who reported moderate to high levels of monitoring at pre-test reported lower levels at follow-up (P = 0.04). These newsletters are a population-based strategy for intervention with parents that show some promise for comprehensive school-based interventions for youth.

Adult↗

PubMed1999

Health risk behaviors of Texas students attending dropout prevention/recovery schools in 1997.

This study determined prevalence of health risk behaviors of 9th through 12th grade students attending dropout prevention/recovery alternative schools in Texas in 1997. Participants were 470 youth whose health risk behaviors were assessed using the Youth Risk Behavior Survey in an anonymous, self-administered format. Behaviors measured included frequency of weapon-carrying and fighting, suicide-related behaviors, substance use, and sexual behaviors. A substantial percentage of alternative school students reported participating in behaviors that placed them at acute or chronic health risk. Differences in the prevalence of risk behaviors were noted by gender, racial/ethnic, and age subgroups. In addition, alternative school students frequently engaged in multiple risk behaviors. These findings suggest a need for comprehensive school-based health education/intervention programs to reduce the prevalence of risk behaviors in populations of alternative school students.

Adolescent↗

PubMed1998

Ecuadorian adolescents and cigarette smoking: a cross-sectional survey.

This study investigates adolescents' attitudes and behaviors toward cigarette smoking in Ecuador. Using social cognitive theory as a basis, the cross-sectional survey focuses attention on such social influences as the smoking habits of family members and peers, as well as on the role of cigarette advertisements. Data on prevalence of actual use, access to cigarettes, and knowledge and attitudes about smoking are also obtained. The survey was conducted during the summer of 1994 in both urban and rural areas. Fifty schools in 40 different communities participated, resulting in a sample of 2,625 adolescents aged 9 to 15 years who completed the self-administered questionnaire. This study was conducted in collaboration with Amigos de las Américas (AMIGOS), an international health organization. Staff and volunteers who participated in projects conducted by AMIGOS in Ecuador worked with local health and education officials to implement the survey. Nearly 9% of students identified themselves as current smokers, 24.5% had experimented with smoking, and 61.1% had never smoked. The results varied significantly by age and gender, with older students and boys smoking at the highest rate. The smoking status of family members and peers also significantly predicted student smoking status. The results from this sample replicate findings from North American samples. Although Ecuadorian students smoke somewhat less than their American counterparts, cigarette smoking in Ecuador is a significant public health problem and clearly warrants a coordinated response. The present study points to several strategies for preventing smoking among youth.

Adolescent↗

PubMed1995

Statistical design of the Child and Adolescent Trial for Cardiovascular Health (CATCH): implications of cluster randomization.

This paper describes some statistical considerations for the Child and Adolescent Trial for Cardiovascular Health (CATCH), a large-scale community health trial sponsored by the National Heart, Lung, and Blood Institute. The trial involves randomization of entire schools rather than individual students to the experimental arms. The paper discussed the implications of this form of randomization for the design and analysis of the trial. The power calculations and analysis plan for the trial are presented in detail. The handling of outmigrating and immigrating students is also discussed.

Adolescent↗

PubMed1995

Community-wide youth nutrition education: long-term outcomes of the Minnesota Heart Health Program.

The Class of 1989 was part of the Minnesota Heart Health Program, a research and demonstration project designed to reduce cardiovascular disease in three intervention communities. This paper describes the long-term outcomes of a school- and community-based intervention on healthy eating behaviors in one intervention and matched reference community. Beginning in the sixth grade (1983), seven annual waves of behavioral measurements were taken from both communities (baseline N = 2376). Self-reported data were collected at each time period including measures of knowledge and preferences for certain foods, and food salting behavior. Data were analyzed using an ANCOVA model adjusting for baseline dependent variable differences, with the school as the unit of analysis. Knowledge, healthy food choices and restraint in food salting behavior variables were significantly higher throughout most of the follow-up period in the intervention community for females. Males also indicated greater knowledge of healthier choices in the intervention community and greater restraint in salting behavior but results are less conclusive for healthy food choices. These results suggest that multiple intervention components such as behavioral education in schools coupled with community-wide health promotion strategies can produce modest but lasting improvement in adolescent knowledge and choices of heart healthy foods and less frequent food salting practices, and that this improvement is most notable among females.

Adolescent↗

PubMed1994

Restrictive smoking policies in the workplace: effects on smoking prevalence and cigarette consumption.

BACKGROUND: Thirty-two worksites participating in a randomized trial of worksite health promotion aimed at reducing smoking and obesity were categorized at baseline and 2 years later as having either restrictive or unrestrictive smoking policies. Between the two assessment points, 16 sites received health promotion interventions. RESULTS: At baseline 15 sites had restrictive policies and 17 unrestrictive policies. Smoking restrictions were associated with significantly lower smoking prevalence and higher lifetime quit rates among ever smokers. They also were associated with more recent quit attempts and lower daily cigarette consumption, although these effects were not significant. Between baseline and follow-up, 9 of the 17 worksites that had few smoking restrictions at baseline became restrictive. Although neither baseline smoking policies nor changes in smoking policy predicted change in smoking prevalence or in the frequency of quit attempts, smokers in sites changing from unrestrictive to restrictive policies reported a significant reduction in daily cigarette consumption. CONCLUSIONS: The worksite health promotion program was successful in reducing smoking prevalence in intervention sites compared to controls. However, the existence of restrictive smoking policies neither helped nor hindered these intervention efforts. The present data are believed to support the idea that restrictive smoking policies have beneficial effects on the smoking habits of employees, but that the magnitude of this effect is modest.

Analysis of Variance↗

PubMed1994

CATCH: classroom process evaluation in a multicenter trial.

The purpose of this paper is to describe the process evaluation model for the classroom curricula of the Child and Adolescent Trial for Cardiovascular Health (CATCH) Project. The process evaluation plan specifically targets how much each curriculum was implemented, to what degree it was implemented as designed, and the barriers to implementation. Additionally, the rationale for each of the process evaluation measures and the instrument development process are presented. Data resulting from these measures will be essential in order to answer questions regarding the internal validity of the main outcomes of the project. Specific examples and sample results are provided from the CATCH third-grade classroom curriculum, which was implemented the first year of CATCH. A discussion also is presented of how the findings from a sample of these measures were used to gain additional insight on the salient features of the curriculum, and how those features may be related to student outcomes.

Adolescent↗

PubMed1994

Longitudinal tracking of adolescent smoking, physical activity, and food choice behaviors.

OBJECTIVES: A major assumption underlying youth health promotion has been that physiological risk factors track from childhood into adulthood. However, few studies have systematically examined how behaviors change during adolescence. This paper describes longitudinal tracking of adolescent health behaviors in two Minnesota Heart Health Program communities. METHODS: Beginning in sixth grade (1983), seven annual waves of behavioral measurements were taken from both communities (baseline n = 2376). Self-reported data included smoking behavior, physical activity, and food preferences. RESULTS: A progressive increase in the change to weekly smoking status was observed across the smoking status categories. As students began to experiment with smoking, they were more likely to either begin to be or remain regular smokers. Tracking of physical activity and food choice variables was also apparent. In nearly all the follow-up periods, the students identified at baseline as measuring high remained high, and those measuring low remained low. CONCLUSIONS: These results indicate that there is evidence of early consolidation and tracking of physical activity, food preference, and smoking behavior. The early consolidation of health behaviors implies that interventions should begin prior to sixth grade, before behavioral patterns are resistant to change. The smoking results suggest that students are experiencing difficulty quitting smoking; thus, youth smoking cessation interventions are warranted.

Adolescent↗

PubMed1994

Predictors of weight change over two years among a population of working adults: the Healthy Worker Project.

The present study examined behavioural predictors of body weight cross-sectionally and longitudinally in a cohort of 1639 male and 1913 female employees in 32 companies participating in a worksite intervention study for smoking cessation and weight control. Dietary intake, current and previous dieting behaviours, and physical activity were examined for their association with body weight over the two-year period. Cross-sectionally in both men and women, history of previous dieting, previous participation in a formal weight loss programme, current dieting and meat consumption were positively related to body weight while high intensity activity was negatively related to body weight. Prospectively, history of participation in a formal weight loss programme and dieting to lose weight at baseline, and increased consumption over time of french fries, dairy products, sweets and meat, independently predicted increases in body weight in women. Women who were dieting to lose weight or who had previously participated in a formal weight loss programme at baseline gained 1.99 lb and 1.74 lb more, respectively, than those who were not dieting to lose weight or who had not previously participated in a formal weight loss programme. Increased exercise, either walking or high intensity activity, predicted decreases in body weight in women (1.76 lb and 1.39 lb, respectively, for each session increase per week). In men, previous participation in a formal weight loss programme predicted increases in body weight over the two-year period. Men who had previously participated in a formal weight loss programme at baseline gained 4.83 lb more than those who had never previously participated in a formal weight loss programme. Increases in consumption of sweets and egg were prospectively related to increases in body weight, while increased walking and high intensity activity were related to decreases in body weight (0.86 lb and 3.54 lb, respectively, for each session increase per week). These results suggest the role that specific diet and exercise behaviours may play in body weight changes over time.

Adult↗

PubMed1993

Effects of a saliva pipeline procedure on adolescent self-reported smoking behavior and youth smoking prevention outcomes.

BACKGROUND: Two strategies to resolve the problem of under- or overreporting of tobacco use among adolescents have been utilized: (a) objective measures for validating self-reports and (b) procedures for improving validity of self-reports, such as the pipeline procedure. The objectives of this article are to investigate the hypothesis that reporting biases may be related to intervention status and to examine what effect such biases would have on interpretation of treatment effects. METHOD: A two-by-two factorial design was used, with the first factor a pipeline manipulation consisting of pipeline versus control condition, and the second factor treatment status, consisting of treatment versus reference schools. Within each of the schools, half of the 9th-grade classrooms were randomly assigned to a pipeline condition and half served as controls. Analysis was conducted with school as the unit of analysis. RESULTS: The main effect for pipeline condition and the significant interaction between treatment and pipeline conditions were not significant. However, the pipeline manipulation did have an effect on the difference detected between treatment and reference schools; 4.3% difference between treatment and reference schools in the control condition versus 9.9% difference in the pipeline condition, both in the direction of a treatment effect. Using saliva thiocyanate as an objective measure of smoking status suggested differential false negative reporting where students in the reference community falsely claimed to be nonsmokers more frequently than in the treatment community (10.04% versus 5.96%). CONCLUSIONS: The reporting bias assessed by the pipeline procedure alone appears to have masked treatment outcome effects. Adjusting the smoking-dependent variable for false negatives seems to have increased the treatment outcome effects even further. This result is contrary to the expectation that the treatment community would experience greater demand pressures to underreport their smoking behavior. Further investigation to address response biases in intervention studies is warranted.

Adolescent↗

PubMed1993

The worksite component of variance: design effects and the Healthy Worker Project.

Variance estimates in worksite health promotion studies depend partly on the intraclass correlation coefficient (ICC). ICC quantifies homogeneity of a variable within worksites. ICC would be zero for randomly formed worksites, but is generally positive because employees tend to share personal characteristics. The ratio comparing the variance estimated from worksite means with that estimated from individuals under simple random sampling is the design effect (DEFF). A DEFF of 1.0 indicates no excess variance due to worksite. The Healthy Worker Project (HWP) was a 32 worksite cross-sectional and longitudinal study of a weight and smoking intervention program. ICCs in cross-sectional surveys for health-related outcome variables ranged from 0.006 to 0.009, DEFFs from 2.0 to 2.6 ICCs/DEFF's in longitudinal analysis were smaller; ICCs ranged from -0.002 to 0.003, DEFFs from 0.7 to 1.5. Positive ICCs substantially increased variance estimates at a single measurement, yet variance of longitudinal analysis was less subject to worksite dependence. It is concluded the worksite component of variance is real and should not be ignored, although the worksite component of variance is small in these longitudinal analyses. This observation should be replicated before it is used in other worksite health promotion research.

Analysis of Variance↗

PubMed1993

Community-wide youth exercise promotion: long-term outcomes of the Minnesota Heart Health Program and the Class of 1989 Study.

The Class of 1989 Study, part of the Minnesota Heart Health Program (MHHP), involved a population-wide research and demonstration project to reduce cardiovascular disease in three intervention communities in the North-Central United States (1980-1993). Beginning in sixth grade (1983), seven annual waves of measurements were taken from students in one of the MHHP intervention communities and its matched pair (baseline N = 2,376). Self-reported data were collected at each time period describing a variety of health-related behavior, including hours of exercise engaged in per week and duration and intensity of regular physical activity. Using school as the unit of analysis, physical activity levels throughout most of the follow-up period were significantly higher in the intervention community for females. Males' average values were higher in the intervention community, but were largely statistically insignificant. Results suggest multiple intervention components such as behavioral education in schools and complementary community-wide strategies can produce lasting improvement in adolescent physical activity, particularly with female students.

Adolescent↗

PubMed1993

The Healthy Worker Project: a work-site intervention for weight control and smoking cessation.

OBJECTIVES: A randomized trial was conducted to evaluate the effectiveness of a work-site health promotion program in reducing obesity and the prevalence of cigarette smoking. METHODS: Thirty-two work sites were randomized to treatment or no treatment for 2 years. Treatment consisted of health education classes combined with a payroll-based incentive system. Evaluation was based on cohort and cross-sectional surveys. RESULTS: Of 10,000 total employees in treatment work sites, 2041 and 270 participated in weight control and smoking cessation programs, respectively. Weight losses averaged 4.8 lbs, and 43% of smoking participants quit. Net 2-year reductions in smoking prevalence in treatment vs control work sites were 4.0% and 2.1% in cross-sectional and cohort surveys, respectively. No treatment effect was found for weight. Treatment effects for smoking prevalence and weight were both positively correlated with participation rates in the intervention programs (r = .45 for smoking and r = .55 for weight). CONCLUSIONS: This work-site health promotion program was effective in reducing smoking prevalence at a cost that is believed to make the investment worthwhile.

Adult↗