Browsing by Author "Steyn, Nelia"

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    Open Access
    Application and interpretation of multiple statistical tests to evaluate validity of dietary intake assessment methods
    (Biomed Central Ltd, 2015) Lombard, Martani; Steyn, Nelia; Charlton, Karen; Senekal, Marjanne
    BACKGROUND:Several statistical tests are currently applied to evaluate validity of dietary intake assessment methods. However, they provide information on different facets of validity. There is also no consensus on types and combinations of tests that should be applied to reflect acceptable validity for intakes. We aimed to 1) conduct a review to identify the tests and interpretation criteria used where dietary assessment methods was validated against a reference method and 2) illustrate the value of and challenges that arise in interpretation of outcomes of multiple statistical tests in assessment of validity using a test data set. METHODS: An in-depth literature review was undertaken to identify the range of statistical tests used in the validation of quantitative food frequency questionnaires (QFFQs). Four databases were accessed to search for statistical methods and interpretation criteria used in papers focusing on relative validity. The identified tests and interpretation criteria were applied to a data set obtained using a QFFQ and four repeated 24-hour recalls from 47 adults (18-65 years) residing in rural Eastern Cape, South Africa. RESULTS: 102 studies were screened and 60 were included. Six statistical tests were identified; five with one set of interpretation criteria and one with two sets of criteria, resulting in seven possible validity interpretation outcomes. Twenty-one different combinations of these tests were identified, with the majority including three or less tests. Coefficient of correlation was the most commonly used (as a single test or in combination with one or more tests). Results of our application and interpretation of multiple statistical tests to assess validity of energy, macronutrients and selected micronutrients estimates illustrate that for most of the nutrients considered, some outcomes support validity, while others do not. CONCLUSIONS: One to three statistical tests may not be sufficient to provide comprehensive insights into various facets of validity. Results of our application and interpretation of multiple statistical tests support the value of such an approach in gaining comprehensive insights in different facets of validity. These insights should be considered in the formulation of conclusions regarding validity to answer a particular dietary intake related research question.
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    Formative assessment of primary school educators in independent schools in Gauteng to advise the need for an intervention for the prevention of non-communicable diseases
    (2021) Drummond, Linda Anne; Steyn, Nelia; Senekal, Marjanne
    Background: Non-communicable diseases (NCDs) are a significant contributor to premature mortality in South Africa. The risks for NCDs among educators in higher socio-economic areas of South Africa have not been studied. The aim of this research was to conduct a formative assessment of grade 4 to 7 educators in independent (non-public) schools in Gauteng to advise the need for an intervention for the prevention of NCDs targeted at these educators. Methods: A cross-sectional, descriptive study design was used to assess the educators' dietary risks for NCDs, their weight status and association with select individual and social factors, and the educators' modifiable and intermediate risk factors for NCDs. A self-administered estimated three-day food record was used to assess dietary and alcohol intake. A self-administered questionnaire was used to collect individual (age, gender, socio-economic status (SES), education level, personal weight and weight loss history, weight status of parents, nutrition knowledge, psychological well-being, body image discordance and satisfaction with body areas) and social factors (influence of significant others on body image) that affect weight status. This questionnaire was also used to assess other modifiable NCD risks (tobacco smoking, physical inactivity) in addition to dietary and alcohol intake, and psychological well-being mentioned. Intermediate NCD risk factors were assessed by taking anthropometric measurements and obtaining non-fasting finger prick blood samples to assess blood glucose, total cholesterol, and triglyceride levels. Results: Eighty-one educators participated and 91% were female. They had a high SES and education level. The median (IQR) age of the educators was 42.0 (35.0; 50.0) years. Sixty-four educators submitted completed food records. The percentage of educators that exceeded the World Health Organisation recommendations for particular dietary parameters were as follows: saturated fat: 91%, trans-fats: 31%, free sugars: 27% and sodium: 28%. Almost three quarters of educators (72%) consumed a lower carbohydrate diet (<45%E) and 94% consumed inadequate amounts of dietary fibre. Thirty percent of educators exceeded the recommended intake for alcohol. The percentage of educators that did not meet the Dietary Reference Intakes for certain micronutrients were as follows: potassium: 100%, vitamin D: 97%, folate: 92%, calcium: 70%, vitamin E: 73%, magnesium: 66%, and vitamin C: 50%. None of the educators had a Dietary Diversity Score (DDS) <4 (mean ± SD DDS: 6.1 ± 1.2) and their diets were varied (mean ± SD Food Variety Score: 13.4 ± 4.5). The ten most frequently consumed items were coffee, brown bread, chicken, full fat cheese, full cream milk, salad, beef, sugar, chocolate, and high fibre breakfast cereals in descending order. As a result, 11 of the 13 measured dietary risk factors outlined by the Global 2017 Diet Collaborators (2019) were present among the educators. The median (IQR) BMI of the total group was 23.9 (21.6; 29.2)kg/m2 . Twenty-seven percent of educators were overweight, 14% obese and 75% had a distorted view of their body size. Overweight/obese educators were significantly more likely to see themselves as smaller than they were (p< .001) and also to have higher levels of dissatisfaction with their bodies in general (p< 0.001), and all the body areas assessed. Female educators wanted to weigh median (IQR) 5 (2; 12)kg less than their actual weight. Sixty-five percent of educators had attempted weight loss in the past two years. Forty-six percent of the educators were psychologically stressed. Nutrition knowledge scores were as follows: poor: 8%, fair: 55% and good: 37%. Significant protectors against being overweight/obese were being younger than 30 years (OR=0.18; 95% CI: 0.04-0.88; p=0.034), not having a distorted body image (OR=0.09; 95% CI: 0.03-0.32; p< 0.001) and being satisfied with their waist (OR=0.29; 95% CI: 0.01-0.85; p=0.025), hips (OR=0.21; 95% CI: 0.07- 0.65; p=0.007) and legs (OR=0.29; 95% CI: 0.10-0.83; p=0.02). All studied NCD risk factors were present in the total group. More prominent risks in those <30 years were a diet high in SSBs, excess sedentary behaviour, elevated triglycerides and smoking, and in those ≥30 years were a diet high in total fat, having a high waist circumference, having elevated cholesterol levels, being overweight/obese and having low PA levels. Nine percent of the educators smoked cigarettes and 32% of educators exceeded alcohol recommendations. The top nine risks were dietary factors including low intake of vegetables, legumes, milk, calcium, fruit, nuts/seeds, fibre, polyunsaturated fat and high intake of red meat. Seventeen percent of educators had insufficient PA levels and 39% spent >4 hours sitting/day. In addition to the levels of psychological distress and overweight/obesity already mentioned, 43% had waist circumferences indicating risk. Eleven percent of educators had a high blood pressure (≥140/≥90 mm Hg), 37% a raised glucose level (≥5.6-< 11.0 mmol/L), 43% a raised total cholesterol level (≥5.0 mmol/L) and 72% a high triglyceride level (≥2.0 mmol/L). Conclusions: Considering the limitations indicated for this study, it can be concluded that the educators teaching at independent schools in Gauteng had a high dietary risk for NCDs, despite consuming a diverse and varied diet. The prevalence of overweight and obesity among the female educators requires intervention. Individual and social factors, that could be used to tailor interventions aimed at preventing or controlling overweight and obesity among this group, were identified. This study provides insights into the modifiable and intermediate risk factors for NCDs among educators teaching at independent schools and indicates the need for effective interventions aimed at reducing their risk for NCDs.
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    Health promotion services for patients having non-comminicable diseases: Feedback from patients and health care providers in Cape Town, South Africa
    (BioMed Central Ltd, 2012) Parker, Whadi-ah; Steyn, Nelia; Levitt, Naomi; Lombard, Carl
    BACKGROUND: Due to a paucity of data regarding the availability and efficacy of equipment, health promotion methods and materials currently used by health professionals for the management of patients with non-communicable diseases (NCDs) at primary health care (PHC) facilities in Cape Town, an audit was undertaken. METHODS: A multi-centre cross-sectional study was undertaken to interview patients (n=580) with NCDs at 30 PHC facilities. A questionnaire was used to obtain information on preferences for health promotion methods for lifestyle modification. Individual semi-structured interviews were conducted with selected health professionals (n=14) and captured using a digital recorder. Data were transferred to the Atlas ti software programme and analysed using a thematic content analysis approach. RESULTS: Blood pressure measurement (97.6%) was the most common diagnostic test used, followed by weight measurement (88.3%), urine (85.7%) and blood glucose testing (80.9%). Individual lifestyle modification counselling was the preferred health education method of choice for the majority of patients. Of the 64% of patients that selected chronic clubs/support groups as a method of choice, only a third rated this as their first choice. Pamphlets, posters and workshops/group counselling sessions were the least preferred methods with only 9%, 13% and 11% of patients choosing these as their first choice, respectively. In an individual counselling setting 44.7% of patients reported that they would prefer to be counselled by a doctor, followed by a nurse (16.9%), health educator (8.8%) and nutrition advisor (4.8%). Health professionals identified numerous barriers to education and counselling. These can be summarised as a lack of resources, including time, space and equipment; staff-related barriers such as staff shortage and staff turnover; and patient-related barriers such as patient load and patient non-compliance. CONCLUSION: The majority of patients attending PHC facilities want to receive lifestyle modification education. There is not however, one specific method that can be regarded as the gold standard. Patients' preferences regarding health education methods differ, and they are more likely to be susceptible to methods that do not involve much reading. Health education materials such as posters, pamphlets and booklets should be used to supplement information received during counselling or support group sessions.
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    "HealthKick": Formative assessment of the health environment in low-resource primary schools in the Western Cape Province of South Africa
    (BioMed Central Ltd, 2012) de Villiers, Anniza; Steyn, Nelia; Draper, Catherine; Fourie, Jean; Barkhuizen, Gerhard; Lombard, Carl; Dalais, Lucinda; Abrahams, Zulfa; Lambert, Estelle
    BACKGROUND: This study evaluated the primary school environment in terms of being conducive to good nutrition practices, sufficient physical activity and prevention of nicotine use, with the view of planning a school-based health intervention. METHODS: A sample of 100 urban and rural disadvantaged schools was randomly selected from two education districts of the Western Cape Education Department, South Africa. A situation analysis, which comprised an interview with the school principal and completion of an observation schedule of the school environment, was done at all schools. RESULTS: Schools, on average, had 560 learners and 16 educators. Principals perceived the top health priorities for learners to be an unhealthy diet (50%) and to far lesser degree, lack of physical activity (24%) and underweight (16%). They cited lack of physical activity (33%) and non-communicable diseases (NCDs; 24%) as the main health priorities for educators, while substance abuse (66%) and tobacco use (31%) were prioritised for parents. Main barriers to health promotion programmes included lack of financial resources and too little time in the time table. The most common items sold at the school tuck shops were crisps (100%), and then sweets (96%), while vendors mainly sold sweets (92%), crisps (89%), and ice lollies (38%). Very few schools (8%) had policies governing the type of food items sold at school. Twenty-six of the 100 schools that were visited had vegetable gardens. All schools reported having physical activity and physical education in their time tables, however, not all of them offered this activity outside the class room. Extramural sport offered at schools mainly included athletics, netball, and rugby, with cricket and soccer being offered less frequently. CONCLUSION: The formative findings of this study contribute to the knowledge of key environmental and policy determinants that may play a role in the health behaviour of learners, their parents and their educators. Evidently, these show that school environments are not always conducive to healthy lifestyles. To address the identified determinants relating to learners it is necessary to intervene on the various levels of influence, i.e. parents, educators, and the support systems for the school environment including the curriculum, food available at school, resources for physical activity as well as appropriate policies in this regard.
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    HealthKick: a nutrition and physical activity intervention for primary schools in low-income settings
    (BioMed Central Ltd, 2010) Draper, Catherine; de Villiers, Anniza; Lambert, Estelle; Fourie, Jean; Hill, Jillian; Dalais, Lucinda; Abrahams, Zulfa; Steyn, Nelia
    BACKGROUND: The burden of non-communicable diseases, including type 2 diabetes, is growing in South Africa. This country has a complex mix of over- and under-nutrition, especially in low-income communities, and concerning levels of physical inactivity in children and youth. This paper describes HealthKick, a school-based nutrition and physical activity intervention in primary schools in these settings aimed at reducing diabetes risk factors.METHODS/DESIGN:This study includes schools within historically disadvantaged, low-income communities from an urban area close to the city of Cape Town and from two rural areas outside of Cape Town, South Africa. The three Educational Districts involved are Metropole North, Cape Winelands and the Overberg. The study has three phases: intervention mapping and formative assessment, intervention development, and outcome and process evaluation. Sixteen schools were purposively selected to participate in the study and randomly allocated as intervention (eight schools) and control (eight schools).The primary aims of HealthKick are to promote healthful eating habits and increase regular participation in health-enhancing physical activity in children, parents and teachers, to prevent overweight, and reduce risk of chronic diseases (particularly type 2 diabetes); as well as to promote the development of an environment within the school and community that facilitates the adoption of healthy lifestyles.The components of HealthKick are: action planning, toolkit (resource guide, a resource box and physical activity resource bin), and an Educators' Manual, which includes a curriculum component.DISCUSSION:This study continues to highlight the key role that educators play in implementing a school-based intervention, but that developing capacity within school staff and stakeholders is not a simple or easy task. In spite of the challenges experienced thus far, valuable findings are being produced from this study, especially from Phase 1. Materials developed could be disseminated to other schools in low-income settings both within and outside of South Africa. Owing to the novelty of the HealthKick intervention in low-income South African primary schools, the findings of the evaluation phase have the potential to impact on policy and practice within these settings.
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    Lifestyle modification education in chronic diseases of lifestyle : insight into counselling provided by health professionals at primary health care facilities in the Western Cape, South Africa
    (2008) Parker, Whadi-ah; Steyn, Nelia; Levitt, Dinky
    The aim of this study is to conduct a formative assessment to explore health professionals’ capacity as well as the conditions within primary health care facilities in the Western Cape Metropole that facilitate or impede the provision of lifestyle modification education and counselling to patients with chronic diseases of lifestyle in order to make recommendations for an intervention programme that utilises available resources.
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    Protocol for the modeling the epidemiologic transition study: a longitudinal observational study of energy balance and change in body weight, diabetes and cardiovascular disease risk
    (BioMed Central Ltd, 2011) Luke, Amy; Bovet, Pascal; Forrester , Terrence; Lambert, Estelle; Plange-Rhule, Jacob; Schoeller, Dale; Dugas, Lara; Durazo-Arvizu, Ramon; Shoham, David; Cooper, Richard; Brage, Soren; Ekelund, Ulf; Steyn, Nelia
    BACKGROUND: The prevalence of obesity has increased in societies of all socio-cultural backgrounds. To date, guidelines set forward to prevent obesity have universally emphasized optimal levels of physical activity. However there are few empirical data to support the assertion that low levels of energy expenditure in activity is a causal factor in the current obesity epidemic are very limited. METHODS/DESIGN: The Modeling the Epidemiologic Transition Study (METS) is a cohort study designed to assess the association between physical activity levels and relative weight, weight gain and diabetes and cardiovascular disease risk in five population-based samples at different stages of economic development. Twenty-five hundred young adults, ages 25-45, were enrolled in the study; 500 from sites in Ghana, South Africa, Seychelles, Jamaica and the United States. At baseline, physical activity levels were assessed using accelerometry and a questionnaire in all participants and by doubly labeled water in a subsample of 75 per site. We assessed dietary intake using two separate 24-hour recalls, body composition using bioelectrical impedance analysis, and health history, social and economic indicators by questionnaire. Blood pressure was measured and blood samples collected for measurement of lipids, glucose, insulin and adipokines. Full examination including physical activity using accelerometry, anthropometric data and fasting glucose will take place at 12 and 24 months. The distribution of the main variables and the associations between physical activity, independent of energy intake, glucose metabolism and anthropometric measures will be assessed using cross-section and longitudinal analysis within and between sites. DISCUSSION: METS will provide insight on the relative contribution of physical activity and diet to excess weight, age-related weight gain and incident glucose impairment in five populations' samples of young adults at different stages of economic development. These data should be useful for the development of empirically-based public health policy aimed at the prevention of obesity and associated chronic diseases.