Physical activity and nutrition behaviour outcomes of a cluster-randomized controlled trial for adults with metabolic syndrome in Vietnam

Background: Metabolic syndrome is prevalent among Vietnamese adults, especially those aged 50-65 years. This study evaluated the effectiveness of a 6 month community-based lifestyle intervention to increase physical activity levels and improve dietary behaviours for adults with metabolic syndrome in Vietnam. Methods: Ten communes, involving participants aged 50-65 years with metabolic syndrome, were recruited from Hanam province in northern Vietnam. The communes were randomly allocated to either the intervention (five communes, n = 214) or the control group (five communes, n = 203). Intervention group participants received a health promotion package, consisting of an information booklet, education sessions, a walking group, and a resistance band. Control group participants received one session of standard advice during the 6 month period. Data were collected at baseline and after the intervention to evaluate programme effectiveness. The International Physical Activity Questionnaire - Short Form and a modified STEPS questionnaire were used to assess physical activity and dietary behaviours, respectively, in both groups. Pedometers were worn by the intervention participants only for 7 consecutive days at baseline and post-intervention testing. To accommodate the repeated measures and the clustering of individuals within communes, multilevel mixed regression models with random effects were fitted to determine the impacts of intervention on changes in outcome variables over time and between groups. Results: With a retention rate of 80.8%, the final sample comprised 175 intervention and 162 control participants. After controlling for demographic and other confounding factors, the intervention participants showed significant increases in moderate intensity activity (P = 0.018), walking (P < 0.001) and total physical activity (P = 0.001), as well as a decrease in mean sitting time (P < 0.001), relative to their control counterparts. Significant improvements in dietary behaviours were also observed, particularly reductions in intake of animal internal organs (P = 0.001) and in using cooking oil for daily meal preparation (P = 0.001). Conclusions: The prescribed community-based physical activity and nutrition intervention programme successfully improved physical activity and dietary behaviours for adults with metabolic syndrome in Vietnam. Trial registration: Australian New Zealand Clinical Trials Registry, ACTRN12614000811606. Registered on 31 July 201

Is informed consent related to success in exercise and diet intervention as evaluated at 12 months? DR's EXTRA study

<p>Abstract</p> <p>Background</p> <p>There is a permanent need to evaluate and develop the ethical quality of scientific research and to widen knowledge about the effects of ethical issues. Therefore we evaluated whether informed consent is related to implementation and success in a lifestyle intervention study with older research participants. There is little empirical research into this topic.</p> <p>Methods</p> <p>The subjects (n = 597) are a subgroup of a random population sample of 1410 men and women aged 57-78 years who are participating in a 4-year randomized controlled intervention trial on the effects of physical exercise and diet on atherosclerosis, endothelial function and cognition. Data were collected in two steps: A questionnaire about informed consent was given to all willing participants (n = 1324) three months after the randomization. Data on implementation and success in the exercise and diet interventions were evaluated at 12 months by intervention-group personnel. The main purpose of the analysis procedure performed in this study was to identify and examine potential correlates for the chosen dependent variables and to generate future hypotheses for testing and confirming the independent determinants for implementation and success. The nature of the analysis protocol is exploratory at this stage.</p> <p>Results</p> <p>About half of the participants (54%) had achieved good results in the intervention. Nearly half of the participants (47%) had added to or improved their own activity in some sector of exercise or diet. Significant associations were found between performance in the interventions and participants' knowledge of the purpose of the study (p < 0.001), and between success in interventions and working status (p = 0.02), and the participants' knowledge of the purpose of the study (p = 0.04).</p> <p>Conclusion</p> <p>The main finding of this study was that those participants who were most aware or had understood the purpose of the study at an early stage had also attained better results at their 12-month intervention evaluation. Therefore, implementation and success in intervention is related to whether subjects receive a sufficient amount and are able to comprehend the information provided i.e. the core principles of informed consent.</p> <p>Trial Registration</p> <p>(ISRCTN 45977199)</p

Linear, Deterministic, and Order-Invariant Initialization Methods for the K-Means Clustering Algorithm

Over the past five decades, k-means has become the clustering algorithm of choice in many application domains primarily due to its simplicity, time/space efficiency, and invariance to the ordering of the data points. Unfortunately, the algorithm's sensitivity to the initial selection of the cluster centers remains to be its most serious drawback. Numerous initialization methods have been proposed to address this drawback. Many of these methods, however, have time complexity superlinear in the number of data points, which makes them impractical for large data sets. On the other hand, linear methods are often random and/or sensitive to the ordering of the data points. These methods are generally unreliable in that the quality of their results is unpredictable. Therefore, it is common practice to perform multiple runs of such methods and take the output of the run that produces the best results. Such a practice, however, greatly increases the computational requirements of the otherwise highly efficient k-means algorithm. In this chapter, we investigate the empirical performance of six linear, deterministic (non-random), and order-invariant k-means initialization methods on a large and diverse collection of data sets from the UCI Machine Learning Repository. The results demonstrate that two relatively unknown hierarchical initialization methods due to Su and Dy outperform the remaining four methods with respect to two objective effectiveness criteria. In addition, a recent method due to Erisoglu et al. performs surprisingly poorly.Comment: 21 pages, 2 figures, 5 tables, Partitional Clustering Algorithms (Springer, 2014). arXiv admin note: substantial text overlap with arXiv:1304.7465, arXiv:1209.196

Application of the Occupational Sitting and Physical Activity Questionnaire (OSPAQ) to office based workers

Background The workplace is a setting where sedentary behaviour is highly prevalent. Accurately measuring physical activity and sedentary behaviour is crucial to assess the impact of behavioural change interventions. This study aimed to evaluate the reliability and criterion validity of the Occupational Sitting and Physical Activity Questionnaire (OSPAQ) and compare with data collected by accelerometers. Methods A test-retest study was undertaken on 99 participants using the OSPAQ. Data were then compared to accelerometer records of 41 participants. Reliability was assessed by paired t-test and intra-class correlations (ICC) via a two-way mixed model based on absolute agreement. Difference and agreement were measured by comparison of mean self-reported data with accelerometer data using the Pearson’s correlation coefficient and Bland-Altman plots. Results The ICCs for minutes spent sitting (0.66), standing (0.83) and walking (0.77) showed moderate to strong test-retest reliability. No significant differences were found between the repeated measurements taken seven days apart. Correlations with the accelerometer readings were moderate. The Bland-Altman plots showed moderate agreement for standing time and walking time but systematic variation for sedentary time. Conclusion The OSPAQ appears to have acceptable reliability and validity measurement properties for application in the office workplace setting

The development, implementation and evaluation of interventions to reduce workplace sitting: a qualitative systematic review and evidence-based operational framework

Background: Prolonged sitting is associated with increased risks of cardiovascular disease, Type 2 diabetes, some cancers, musculoskeletal disorders and premature mortality. Workplaces contribute to a large proportion of daily sitting time, particularly among office-based workers. Interventions to reduce workplace sitting therefore represent important public health initiatives. Previous systematic reviews suggest such interventions can be effective but have reported wide variations. Further, there is uncertainty as to whether effectiveness in controlled trials can be replicated when implemented outside the research setting. The aims of this review are to identify factors important for the implementation of workplace sitting interventions and to translate these findings into a useful operational framework to support the future implementation of such interventions. Methods: A qualitative systematic review was conducted. Four health and social science databases were searched for studies set in the workplace, with office-based employees and with the primary aim of reducing workplace sitting. Extracted data were primarily from author descriptions of interventions and their implementation. Inductive thematic analysis and synthesis was undertaken. Results: Forty studies met the inclusion criteria. Nine descriptive themes were identified from which emerged three higher-order analytical themes, which related to the development , implementation and evaluation of workplace sitting interventions. Key findings inc luded: the importance of groundi ng interventions in theory; utilising participative approaches during intervention development and implementation; and c onducting comprehensive proce ss and outcome evaluations. There was a general under-reporting of info rmation relating to the context within which workplace sitting interventions were implemented, such as details of local organisation processes and structures, as well as the wider political and economic landscape, which if present would aid the translation of knowledge into “ real-world ” settings. Conclusions: These findings provided the basis for an operational framework, which is a representation of all nine descriptive themes and three higher-order analytical themes, to support workplace sitting intervention development, implementation and evaluation. Once tested and refined, this framework has the potential to be incorporated into a practical toolkit, which could be used by a range of organisations to develop, implement and evaluate their own interventions to reduce workplace sitting time amongst staff

Web-based interventions to promote physical activity by older adults: promising perspectives for a public health challenge

Regular physical activity is associated with a wide range of health benefits. As population age, promotion of physical activity should specifically target older adults, an expanding group involving potential higher health care costs in the near future. Innovative interventions focusing on physical activity behaviors of senior adults exposed promising results, most recently through the use of the Internet. If seniors and Internet are generally considered as two opposite concepts, arguments in favour of bringing them together in a public health perspective have been identified by the recent literature. Older adults are the fastest growing group of Internet users and are more prone than younger to use it for health-related subjects. Web-based interventions are effective in many health promotion sectors, including physical activity. This is particularly true when interventions target the environmental determinants of each senior citizen and are specifically designed for this population. Those early research findings must clearly be extended, particularly regarding to the long term effects of Webbased physical activity interventions. Solutions that will reduce the high dropout rate recorded in the existing literature must also be considered as a priority in order to ensure the development of this forward-looking field of research