Deborah L. Dewar
University of Newcastle
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Deborah L. Dewar.
JAMA Pediatrics | 2012
David R. Lubans; Philip J. Morgan; Anthony D. Okely; Deborah L. Dewar; Clare E. Collins; Marijka Batterham; Robin Callister; Ronald C. Plotnikoff
OBJECTIVE To evaluate the impact of a 12-month multicomponent school-based obesity prevention program, Nutrition and Enjoyable Activity for Teen Girls among adolescent girls. DESIGN Group randomized controlled trial with 12-month follow-up. SETTING Twelve secondary schools in low-income communities in the Hunter and Central Coast regions of New South Wales, Australia. PARTICIPANTS Three hundred fifty-seven adolescent girls aged 12 to 14 years. INTERVENTION A multicomponent school-based intervention program tailored for adolescent girls. The intervention was based on social cognitive theory and included teacher professional development, enhanced school sport sessions, interactive seminars, nutrition workshops, lunch-time physical activity sessions, handbooks and pedometers for self-monitoring, parent newsletters, and text messaging for social support. MAIN OUTCOME MEASURES Body mass index (BMI, calculated as weight in kilograms divided by height in meters squared), BMI z score, body fat percentage, physical activity, screen time, dietary intake, and self-esteem. RESULTS After 12 months, changes in BMI (adjusted mean difference, -0.19; 95% CI, -0.70 to 0.33), BMI z score (mean, -0.08; 95% CI, -0.20 to 0.04), and body fat percentage (mean, -1.09; 95% CI, -2.88 to 0.70) were in favor of the intervention, but they were not statistically different from those in the control group. Changes in screen time were statistically significant (mean, -30.67 min/d; 95% CI, -62.43 to -1.06), but there were no group by time effects for physical activity, dietary behavior, or self-esteem. CONCLUSIONS A school-based intervention tailored for adolescent girls from schools located in low-income communities did not significantly reduce BMI gain. However, changes in body composition were of a magnitude similar to previous studies and may be associated with clinically important health outcomes. TRIAL REGISTRATION anzctr.org.au Identifier: 12610000330044.
BMC Public Health | 2010
David R. Lubans; Philip J. Morgan; Deborah L. Dewar; Clare E. Collins; Ronald C. Plotnikoff; Anthony D. Okely; Marijka Batterham; T. Finn; Robin Callister
BackgroundChild and adolescent obesity predisposes individuals to an increased risk of morbidity and mortality from a range of lifestyle diseases. Although there is some evidence to suggest that rates of pediatric obesity have leveled off in recent years, this has not been the case among youth from low socioeconomic backgrounds. The purpose of this paper is to report the rationale, study design and baseline findings of a school-based obesity prevention program for low-active adolescent girls from disadvantaged secondary schools.Methods/DesignThe Nutrition and Enjoyable Activity for Teen Girls (NEAT Girls) intervention will be evaluated using a group randomized controlled trial. NEAT Girls is a 12-month multi-component school-based intervention developed in reference to Social Cognitive Theory and includes enhanced school sport sessions, interactive seminars, nutrition workshops, lunch-time physical activity (PA) sessions, PA and nutrition handbooks, parent newsletters, pedometers for self-monitoring and text messaging for social support. The following variables were assessed at baseline and will be completed again at 12- and 24-months: adiposity, objectively measured PA, muscular fitness, time spent in sedentary behaviors, dietary intake, PA and nutrition social-cognitive mediators, physical self-perception and global self-esteem. Statistical analyses will follow intention-to-treat principles and hypothesized mediators of PA and nutrition behavior change will be explored.DiscussionNEAT Girls is an innovative intervention targeting low-active girls using evidence-based behavior change strategies and nutrition and PA messages and has the potential to prevent unhealthy weight gain and reduce the decline in physical activity and poor dietary habits associated with low socio-economic status. Few studies have reported the long-term effects of school-based obesity prevention programs and the current study has the potential to make an important contribution to the field.Trial registrationAustralian New Zealand Clinical Trials Registry No: ACTRN12610000330044
International Journal of Behavioral Nutrition and Physical Activity | 2012
Deborah L. Dewar; David R. Lubans; Ronald C. Plotnikoff; Philip J. Morgan
BackgroundThis study aimed to develop and evaluate the reliability and factorial validity, of social-cognitive measures related to adolescent healthy eating behaviors.MethodsA questionnaire was developed based on constructs from Bandura’s Social Cognitive Theory and included the following scales: self-efficacy, intentions (proximal goals), situation (perceived environment), social support, behavioral strategies, outcome expectations and expectancies. The questionnaire was administered with a two week test-retest among secondary school students (n = 173, age = 13.72 ± 1.24). Confirmatory factor analysis was employed to examine model-fit for each scale using multiple indices including: chi-square index, comparative-fit index (CFI), goodness-of-fit index (GFI), and the root mean square error of approximation (RMSEA). Reliability properties were also examined (ICC and Cronbach’s alpha).ResultsThe reliability and factorial validity of each scale is supported: fit indices suggest each model to be an adequate-to-exact fit to the data; internal consistency was acceptable-to-good (α=0.65−0.79); rank order repeatability was strong (ICC = 0.81−0.89).Conclusions and implicationsResults support the reliability and factorial validity of social cognitive scales relating to healthy eating behaviors among adolescents. As such, the developed scales have utility for identifying potential social cognitive correlates of adolescent dietary behavior, mediators of dietary behavior change and validity testing of theoretical models based on Social Cognitive Theory.
BMC Public Health | 2012
David R. Lubans; Phillip J. Morgan; Kristen Weaver; Robin Callister; Deborah L. Dewar; Sarah A. Costigan; T. Finn; Jordan J. Smith; Lee Upton; Ronald C. Plotnikoff
BackgroundMany Australian children are insufficiently active to accrue health benefits and physical activity (PA) levels are consistently lower among youth of low socio-economic position. PA levels decline dramatically during adolescence and evidence suggests that competency in a range of fundamental movement skills (FMS) may serve as a protective factor against this trend.Methods/designThe Supporting Children’s Outcomes Using Rewards Exercise and Skills (SCORES) intervention is a multi-component PA and FMS intervention for primary schools in low-income communities, which will be evaluated using a group randomized controlled trial. The socio-ecological model provided a framework for the 12-month intervention, which includes the following components: teacher professional learning, student leadership workshops (including leadership accreditation and rewards, e.g., stickers, water bottles), PA policy review, PA equipment packs, parental engagement via newsletters, FMS homework and a parent evening, and community partnerships with local sporting organizations. Outcomes will be assessed at baseline, 6- and 12-months. The primary outcomes are PA (accelerometers), FMS (Test of Gross Motor Development II) and cardiorespiratory fitness (multi-stage fitness test). Secondary outcomes include body mass index [using weight (kg)/height (m2)], perceived competence, physical self-esteem, and resilience. Individual and environmental mediators of behavior change (e.g. social support and enjoyment) will also be assessed. The System for Observing Fitness Instruction Time will be used to assess the impact of the intervention on PA within physical education lessons. Statistical analyses will follow intention-to-treat principles and hypothesized mediators of PA behavior change will be explored.DiscussionSCORES is an innovative primary school-based PA and FMS intervention designed to support students attending schools in low-income communities to be more skilled and active. The findings from the study may be used to guide teacher pre-service education, professional learning and school policy in primary schools.Trial registrationAustralian New Zealand Clinical Trials Registry No: ACTRN12611001080910
Appetite | 2014
Clare E. Collins; Deborah L. Dewar; Tracy L. Schumacher; T. Finn; Philip J. Morgan; David R. Lubans
Poor dietary habits and obesity are more prevalent in lower socio-economic status (SES) communities. The NEAT Girls cluster randomized controlled trial was a school-based obesity prevention program targeting adolescent girls in low SES schools in NSW, Australia. The aim was to evaluate the 12-month impact of key nutrition program messages on dietary intake and food behaviors. Diet was assessed using a validated semi-quantitative food frequency questionnaire (FFQ). Individual foods were categorized into nutrient-dense or energy-dense, nutrient-poor food groups and the percentage contribution to total energy intake calculated. Participants were aged 13.2±0.5years (n=330). There were no statistically significant group-by-time effects for dietary intake or food related behaviors, with 12-month trends suggesting more intervention group girls had improved water intakes (59% consuming⩽three glasses per day to 54% at 12 months vs. 50% to 61% in controls, p=0.052), with a greater proportion consuming < one sweetened beverage per day (24-41% vs. 34-37% in controls, p=0.057). Further research including more intensive nutrition intervention strategies are required to evaluate whether dietary intake in adolescent girls attending schools in low SES communities can be optimized.
Preventive Medicine | 2016
Ana Carolina Barco Leme; David R. Lubans; Paulo Henrique Guerra; Deborah L. Dewar; Erika Christiane Toassa; Sonia Tucunduva Philippi
BACKGROUND School-based trials to prevent and reduce prevalence of pediatric obesity in low-income countries are necessary. In Brazil, addressing adolescent obesity is a public health priority. OBJECTIVE To evaluate the impact of a group randomized controlled trial involving a 6-month multicomponent school-based obesity prevention program targeting adolescent girls. METHODS The Healthy Habits, Healthy Girls-Brazil program recruited participants (n=253; 16.05±0.05 years) from ten eligible public technical schools in São Paulo, Brazil. The program was adapted from an Australian intervention study, which is based on the Social Cognitive Theory. The primary outcome measure was body mass index (BMI), and secondary outcomes included BMI z score, waist circumference, and various sedentary and dietary health-related behaviours. RESULTS Although changes in BMI were not statistically significant, differences favored the intervention group (adjusted mean difference, -0.26kg/m(2),se SE=0.018, p=0.076). Statistically significant intervention effects were found for waist circumference (-2.28cm; p=, p=0.01), computer screen time on the weekends (0.63h/day, p; p=0.02), total sedentary activities on the weekends (-0.92h/day, p<0.01), and vegetable intake (1.16servings/day, p=0.01). CONCLUSION These findings provide some evidence for the benefit of a school-based intervention to prevent unhealthy weight gain in adolescent girls living in low-income communities.
BMJ Open | 2016
David R. Lubans; Jordan J. Smith; Louisa Peralta; Ronald C. Plotnikoff; Anthony D. Okely; Jo Salmon; Narelle Eather; Deborah L. Dewar; Sarah G. Kennedy; Chris Lonsdale; Toni A. Hilland; Paul A. Estabrooks; T. Finn; Emma Pollock; Philip J. Morgan
Introduction Physical inactivity has been described as a global pandemic. Interventions aimed at developing skills in lifelong physical activities may provide the foundation for an active lifestyle into adulthood. In general, school-based physical activity interventions targeting adolescents have produced modest results and few have been designed to be ‘scaled-up’ and disseminated. This study aims to: (1) assess the effectiveness of two physical activity promotion programmes (ie, NEAT and ATLAS) that have been modified for scalability; and (2) evaluate the dissemination of these programmes throughout government funded secondary schools. Methods and analysis The study will be conducted in two phases. In the first phase (cluster randomised controlled trial), 16 schools will be randomly allocated to the intervention or a usual care control condition. In the second phase, the Reach, Effectiveness, Adoption, Implementation and Maintenance (Re-AIM) framework will be used to guide the design and evaluation of programme dissemination throughout New South Wales (NSW), Australia. In both phases, teachers will be trained to deliver the NEAT and ATLAS programmes, which will include: (1) interactive student seminars; (2) structured physical activity programmes; (3) lunch-time fitness sessions; and (4) web-based smartphone apps. In the cluster RCT, study outcomes will be assessed at baseline, 6 months (primary end point) and 12-months. Muscular fitness will be the primary outcome and secondary outcomes will include: objectively measured body composition, cardiorespiratory fitness, flexibility, resistance training skill competency, physical activity, self-reported recreational screen-time, sleep, sugar-sweetened beverage and junk food snack consumption, self-esteem and well-being. Ethics and dissemination This study has received approval from the University of Newcastle (H-2014-0312) and the NSW Department of Education (SERAP: 2012121) human research ethics committees. This study is funded by the Australian Research Council (FT140100399) and the NSW Department of Education. Trial registration number ACTRN12615000360516; Pre-results.
Medicine and Science in Sports and Exercise | 2018
Sarah G. Kennedy; Jordan J. Smith; Philip J. Morgan; Louisa Peralta; Toni A. Hilland; Narelle Eather; Chris Lonsdale; Anthony D. Okely; Ronald C. Plotnikoff; Jo Salmon; Deborah L. Dewar; Paul A. Estabrooks; Emma Pollock; T. Finn; David R. Lubans
Purpose Guidelines recommend that young people engage in muscle-strengthening activities on at least 3 d·wk−1. The purpose of this study was to examine the effect of a school-based intervention focused on resistance training (RT) for adolescents. Methods The “Resistance Training for Teens” intervention was evaluated using a cluster-randomized, controlled trial with 607 adolescents (50.1% girls; 14.1 ± 0.5 yr) from 16 secondary schools. Teachers were trained to deliver the intervention, which included the following: (i) an interactive student seminar; (ii) a structured physical activity program, focused on RT; (iii) lunchtime fitness sessions; and (iv) Web-based smartphone apps. The primary outcome was muscular fitness (MF) and secondary outcomes included body mass index, RT skill competency, flexibility, physical activity, self-efficacy, and motivation. Assessments were conducted at baseline, 6 months (postprogram; primary end point), and 12 months (follow-up). Outcomes were assessed using linear mixed models, with three potential moderators tested using interaction terms (and subgroup analyses where appropriate). Results For the primary outcome (MF), a group–time effect was observed at 6 months for the upper body (2.0 repetitions; 95% confidence interval (CI), 0.8–3.2), but not the lower body (−1.4 cm; 95% CI, −4.7–1.9). At 6 months, there were intervention effects for RT skill competency and self-efficacy, but no other secondary outcomes. Effects for upper body MF and RT skill competency were sustained at 12 months. Despite overall no effect for body mass index, there was a group–time effect at 12 months among students who were overweight/obese at baseline (−0.55 kg·m−2; 95% CI, −1.01 to −0.08). Conclusions The school-based RT intervention resulted in immediate and sustained improvements in upper body MF and RT skill competency, demonstrating an effective and scalable approach to delivering RT within secondary schools.
Nutrition & Dietetics | 2014
Tracy L. Schumacher; Deborah L. Dewar; David R. Lubans; Philip J. Morgan; Jane Watson; Maya Guest; Tracy Burrows; Robin Callister; Clare E. Collins
Aim Overweight and obesity prevalence is high among adolescent girls of low socioeconomic position and this increases their risk of cardiovascular disease and metabolic disorders in adulthood. The aim of this present study was to describe the dietary patterns of adolescent girls in terms of the relative contribution of core food groups to overall diet and by weight status category. Methods Year 8 female students were recruited from schools in low-income communities. Weight status (i.e. underweight, healthy weight, overweight, obese) was determined using age- and sex-adjusted body mass index (BMI; z score). Dietary intakes were assessed using a validated semi-quantitative food frequency questionnaire. Individual foods were collated into core food group or energy-dense, nutrient-poor categories in line with the Australian Guide to Healthy Eating (AGHE) and the percentage contribution to total energy intake calculated. Results Participants (n = 332) were (mean ± SD) 13.7 ± 0.4 years old with BMI z score 0.63 ± 1.22. Few girls met AGHE core food group recommendations for daily serves; meat and substitutes 69.3%, vegetables 28.6%, fruit 23.8%, dairy 15.7% and breads/cereals 5.7%. Total percentage energy derived from energy-dense, nutrient-poor foods was 46.6% (37.2–54.6%) (median (interquartile range)), with takeaways 9.8% (7.0–13.6%), confectionery 7.0% (4.1–10.9%) and packaged snacks 6.8% (4.0–10.7%), with no significant differences by weight status. Conclusions Core food intakes are poor with excessive consumption of energy-dense, nutrient-poor foods in these adolescent girls. Nutrition education programs targeting this population are needed to address this imbalance. Strategies could include substitution of unhealthy snacks for core food items and greater inclusion of core foods within main meals.
American Journal of Preventive Medicine | 2013
Deborah L. Dewar; Philip J. Morgan; Ronald C. Plotnikoff; Anthony D. Okely; Clare E. Collins; Marijka Batterham; Robin Callister; David R. Lubans