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DIET@NET: Best Practice Guidelines for dietary assessment in health research

BackgroundDietary assessment is complex, and strategies to select the most appropriate dietary assessment tool (DAT) in epidemiological research are needed. The DIETary Assessment Tool NETwork (DIET@NET) aimed to establish expert consensus on Best Practice Guidelines (BPGs) for dietary assessment using self-report.MethodsThe BPGs were developed using the Delphi technique. Two Delphi rounds were conducted. A total of 131 experts were invited, and of these 65 accepted, with 48 completing Delphi round I and 51 completing Delphi round II. In all, a total of 57 experts from North America, Europe, Asia and Australia commented on the 47 suggested guidelines.ResultsForty-three guidelines were generated, grouped into the following four stages: Stage I. Define what is to be measured in terms of dietary intake (what? who? and when?); Stage II. Investigate different types of DATs; Stage III. Evaluate existing tools to select the most appropriate DAT by evaluating published validation studies; Stage IV. Think through the implementation of the chosen DAT and consider sources of potential biases.ConclusionsThe Delphi technique consolidated expert views on best practice in assessing dietary intake. The BPGs provide a valuable guide for health researchers to choose the most appropriate dietary assessment method for their studies. These guidelines will be accessible through the Nutritools website, www.nutritools.org.

Eating at Food Outlets and “On the Go” Is Associated with Less Healthy Food Choices in Adults: Cross-Sectional Data from the UK National Diet and Nutrition Survey Rolling Programme (2008–2014)

Eating location has been linked with variations in diet quality including the consumption of low-nutrient energy-dense food, which is a recognised risk factor for obesity. Cross-sectional data from 4736 adults aged 19 years and over from Years 1–6 of the UK National Diet and Nutrition Survey (NDNS) Rolling Programme (RP) (2008–2014) were used to explore food consumption patterns by eating location. Eating location was categorized as home, work, leisure places, food outlets and “on the go”. Foods were classified into two groups: core (included in the principal food groups and considered important/acceptable within a healthy diet) and non-core (all other foods). Out of 97,748 eating occasions reported, the most common was home (67–90% of eating occasions). Leisure places, food outlets and “on the go” combined contributed more energy from non-core (30%) than from core food (18%). Analyses of modulating factors revealed that sex, income, frequency of eating out and frequency of drinking were significant factors affecting consumption patterns (p < 0.01). Our study provides evidence that eating patterns, behaviours and resulting diet quality vary by location. Public health interventions should focus on availability and access to healthy foods, promotion of healthy food choices and behaviours across multiple locations, environments and contexts for food consumption.

P29 Best practice guidance for dietary assessment in research: DIET@NET Guidelines

Background Accurate assessment of dietary intake is important for planning, implementing of health promotion and when evaluating the effectiveness of public health interventions. However, measuring dietary intake is one of the most challenging aspects of public health research as no dietary method can measure dietary intake without error. Therefore, strategies that support researchers to choose the most appropriate dietary assessment method will help to strengthen research in this field. This study, undertaken for the Diet@net consortium aims to establish expert consensus on best practice guidelines (BPG) for carrying out dietary assessment in order to help non-experts in collecting dietary information. Methods The guidelines were developed through a Delphi consultation technique (Moher recommendations). Two Delphi rounds were conducted using self-administered questionnaires, asking for prioritisation of suggested guidelines. Twelve expert members of the BPG-working group reviewed findings from participants and finalised the guidelines. Results One hundred and thirty-experts were invited to take part, of whom 65 agreed to participate. Forty-eight completed Delphi-I and 51 Delphi-II. Overall, a total of 57 experts from different countries contributed feedback; these included nutritional epidemiologists, statisticians, and public health specialists. Initially, 47 statements were included in the guidelines. Following both Delphi rounds this was reduced to 43. The final consensus BPG includes four main stages with eight sub-sections. These stages are summarised as follows: Stage I. researchers need to define what is to be measured in terms of dietary intake to guide the choice of the most suitable Dietary Assessment Tool (DAT). Considering the ‘who?’, ‘what?’, and ‘when?’ of the study participants. Stage II. Investigate different types of DAT and appraise their appropriateness for the research question. Stage III. Evaluate existing tools to fine-tune choice of the most appropriate DAT by evaluating published validation studies, and considering the need for any modification or updating of the existing tools. Stage IV. Think about the implementation of the chosen DATs in the population of interest. Also, by addressing the source and range of the potential biases when using chosen DAT, aiming to minimise these where possible. Conclusion Delphi techniques allowed us to synthesise experts’ consensus on best practice in assessing dietary intake. The BPG will help non-expert researchers to consider key factors when selecting a DAT. These guidelines will be included on the Nutritools website (http://www.food.leeds.ac.uk/nutritools). Nutritools will host interactive dietary assessment tools and guidance for nutrition researchers, healthcare practitioners and other scientists.

Eating at food outlets and leisure places and “on the go” is associated with less-healthy food choices than eating at home and in school in children: cross-sectional data from the UK National Diet and Nutrition Survey Rolling Program (2008–2014)

ABSTRACT Background Where children eat has been linked to variations in diet quality, including the consumption of low-nutrient, energy-dense food, a recognized risk factor for obesity. Objective The aim of this study was to provide a comprehensive analysis of consumption patterns and nutritional intake by eating location in British children with the use of a nationally representative survey. Design Cross-sectional data from 4636 children (80,075 eating occasions) aged 1.5–18 y from the UK National Diet and Nutrition Survey Rolling Program (2008–2014) were analyzed. Eating locations were categorized as home, school, work, leisure places, food outlets, and “on the go.” Foods were classified into core (considered important or acceptable within a healthy diet) and noncore (all other foods). Other variables included the percentage of meals eaten at home, sex, ethnicity, body mass index, income, frequency of eating out, takeaway meal consumption, alcohol consumption, and smoking. Results The main eating location across all age groups was at home (69–79% of eating occasions), with the highest energy intakes. One-third of children from the least-affluent families consumed ≤25% of meals at home. Eating more at home was associated with less sugar and takeaway food consumption. Eating occasions in leisure places, food outlets, and “on the go” combined increased with age, from 5% (1.5–3 y) to 7% (11–18 y), with higher energy intakes from noncore foods in these locations. The school environment was associated with higher intakes of core foods and reduced intakes of noncore foods in children aged 4–10 y who ate school-sourced foods. Conclusions Home and school eating are associated with better food choices, whereas other locations are associated with poor food choices. Effective, sustained initiatives targeted at behaviors and improving access to healthy foods in leisure centers and food outlets, including food sold to eat “on the go,” may improve food choices. Home remains an important target for intervention through family and nutrition education, outreach, and social marketing campaigns. This trial was registered with the ISRTCN registry (https://www.isrctn.com) as ISRCTN17261407.

A Disaggregation Methodology to Estimate Intake of Added Sugars and Free Sugars: An Illustration from the UK National Diet and Nutrition Survey

Various and inconsistent definitions for free and added sugars are used in the consideration and assessment of dietary intakes across public health, presenting challenges for nutritional surveillance, research, and policy. Furthermore, analytical methods to identify those sugars which are not naturally incorporated into the cellular structure of foods are lacking, thus free and added sugars are difficult to estimate in an efficient and accurate way. We aimed to establish a feasible and accurate method that can be applied flexibly to different definitions. Based on recipe disaggregation, our method involved five steps and showed good repeatability and validity. The resulting Free Sugars Database provided data for seven components of sugars; (1) table sugar; (2) other sugars; (3) honey; (4) fruit juice; (5) fruit puree; (6) dried fruit; and (7) stewed fruit, for ~9000 foods. Our approach facilitates a standardized and efficient assessment of added and free sugars, offering benefit and potential for nutrition research and surveillance, and for the food industry, for example to support sugar reduction and reformulation agendas.

Traditional methods v. new technologies – dilemmas for dietary assessment in large-scale nutrition surveys and studies: a report following an international panel discussion at the 9th International Conference on Diet and Activity Methods (ICDAM9), Brisbane, 3 September 2015

The aim of the present paper is to summarise current and future applications of dietary assessment technologies in nutrition surveys in developed countries. It includes the discussion of key points and highlights of subsequent developments from a panel discussion to address strengths and weaknesses of traditional dietary assessment methods (food records, FFQ, 24 h recalls, diet history with interviewer-assisted data collection) v. new technology-based dietary assessment methods (web-based and mobile device applications). The panel discussion ‘Traditional methods v. new technologies: dilemmas for dietary assessment in population surveys’, was held at the 9th International Conference on Diet and Activity Methods (ICDAM9), Brisbane, September 2015. Despite respondent and researcher burden, traditional methods have been most commonly used in nutrition surveys. However, dietary assessment technologies offer potential advantages including faster data processing and better data quality. This is a fast-moving field and there is evidence of increasing demand for the use of new technologies amongst the general public and researchers. There is a need for research and investment to support efforts being made to facilitate the inclusion of new technologies for rapid, accurate and representative data.

Validation of thes use of p-aminobenzoic acid to determine completeness of 24 h urine collections in surveys of diet and nutrition

Sodium intake is assessed using 24 h urinary excretion; it is important to ensure urine collections are complete. This can be validated by monitoring urinary excretion of p-aminobenzoic acid (PABA) administered in tablet form at intervals during the urine collection. Unavoidable change of PABA tablet supplier and analytical procedure required re-establishment of the thresholds consistent with a complete collection. Reference ranges for adults without reported intestinal or renal disease were determined by HPLC (70–103%) and colorimetry (84–120%). Some individuals excreted a small, measurable amount of PABA the following day but this did not represent the balance of the PABA ingested. Assay of the PABA tablets confirmed the stated dose (80 mg) and demonstrated their stability up to 8 years (duration of study) at room temperature. These tablets have been used and the reference ranges applied in UK national population surveys since 2008.

Development of Nutritools, an interactive dietary assessment tools website, for use in health research

Abstract Background Measuring dietary intake is difficult, and strategies that enable researchers to select the most appropriate dietary assessment tools are needed. The aim of this work was to improve the quality of dietary data collected in epidemiological studies. Therefore, the DIETary Assessment Tools NETwork (DIET@NET) partnership, a network of scientific experts, has created the Nutritools website. Methods Development of the Nutritools website was divided into three strands: creation of best practice guidelines, developed with the Delphi technique to obtain expert views (the guidelines enable researchers to choose the most appropriate dietary assessment tool for their work); creation of an interactive dietary assessment tool e-library, with eligible dietary assessment tools being identified through a systematic review of reviews that searched seven databases; and creation of an online interface between food tables and dietary assessment tools—namely, the Food Questionnaire Creator (FQC). The work was guided by the DIET@NET partnership. Findings Interactive dietary assessment guidelines were generated with feedback from 57 international experts. 43 guidelines and a summary of the strengths and weaknesses of the dietary assessment methods were included. The dietary assessment tool e-library included data for 62 UK validated tools, which were obtained from 43 systematic reviews identified. The tool library will provide in-depth information about the tools, validation study characteristics, and results. This information is also provided visually through bubble and summary plots, allowing easier comparison between the dietary assessment tools. The FQC was based on the principles of common food frequency questionnaires and allows users to create and develop new online food questionnaires. Users can map their online questionnaires to the latest UK food database (McCance and Widdowsons Composition of Foods, 7th edn). The FQC will also host a number of validated dietary assessment tools that have been adapted for online use. Interpretation The DIET@NET partnership has created a unique dietary assessment reference website (live from November, 2017) using expert guidance and systematic review. The website allows visual comparison of dietary assessment tools and hosts validated, interactive tools. The best practice guidelines assist researchers in selecting the most appropriate tool for their study. Researchers can access validated dietary assessment tools through the e-library and create their own using the FQC. Funding UK Medical Research Council (grant no MR/L02019X/1).