The aim of the Boost study was to produce a persistent increase in fruit and vegetable consumption among 13-year-olds. This paper describes the development, implementation and evaluation of a school-and community-based, multi-component intervention guided by theory, evidence, and best practice.
We used the Intervention Mapping protocol to guide the development of the intervention. Programme activities combined environmental and educational strategies and focused on increasing access to fruit and vegetables in three settings: School: Daily provision of free fruit and vegetables; a pleasant eating environment; classroom curricular activities; individually computer tailored messages; one-day-workshop for teachers. Families: school meeting; guided child-parent activities; newsletters. Local community: guided visits in grocery stores and local area as part of classroom curriculum; information sheets to sports-and youth clubs.The Boost study employed a cluster-randomised controlled study design and applied simple two-stage cluster sampling: A random sample of 10 municipalities followed by a random sample of 4 schools within each municipality (N = 40 schools). Schools were randomised into a total of 20 intervention-and 20 control schools. We included all year 7 pupils except those from school classes with special needs. Timeline: Baseline survey: August 2010. Delivery of intervention: September 2010-May 2011. First follow-up survey: May/June 2011. Second follow-up survey: May/June 2012.
Daily mean intake of fruit and vegetables and habitual fruit and vegetable intake measured by validated 24-hour recall-and food frequency questionnaires.
determinants of fruit and vegetable intake, positive side-effects and unintended adverse effects. Implementation was monitored by thorough process evaluation.
The baseline data file included 2,156 adolescents (95%). There was baseline equivalence between intervention-and control groups for sociodemographics, primary outcomes, and availability at home, school and sports-and youth clubs. Significantly larger proportions of pupils in the control group had parents born in Denmark. The study will provide insights into effective strategies to increase fruit and vegetable intake among teenagers. The study will gain knowledge on implementation processes, intervention effects in population subgroups with low intake, and opportunities for including local communities in interventions.
BACKGROUND/AIMS: An adequate fruit and vegetable intake provides essential nutrients and nutritive compounds and is considered an important part of a healthy lifestyle. No simple instrument has been available for the assessment of fruit and vegetable intake as well as its determinants in school-aged children applicable in different European countries. Within the Pro Children Project, such an instrument has been developed. This paper describes the cross-sectional survey in 11-year-olds in 9 countries. METHODS: The cross-sectional survey used nationally, and in 2 countries regionally, representative samples of schools and classes. The questionnaires, including a precoded 24-hour recall component and a food frequency part, were completed in the classroom. Data were treated using common syntax files for portion sizes and for merging of vegetable types into four subgroups. RESULTS: The results show that the fruit and vegetable intake in amounts and choice were highly diverse in the 9 participating countries. Vegetable intake was in general lower than fruit intake, boys consumed less fruit and vegetables than girls did. The highest total intake according to the 24-hour recall was found in Austria and Portugal, the lowest in Spain and Iceland. CONCLUSION: The fruit and vegetable intake in 11-year-old children was in all countries far from reaching population goals and food-based dietary guidelines on national and international levels.
OBJECTIVE: To describe and compare fruit and vegetable intakes of mothers of 11-year-old children across Europe. METHODS: Cross-sectional surveys were carried out in 9 European countries in October/November 2003. Self-administered questionnaires assessing fruit and vegetable consumption were used for data collection. The current paper presents dietary intake data obtained by a precoded 24-hour recall and a food frequency questionnaire. RESULTS: The consumption levels of fruit and vegetables (without fruit juice) were in line with World Health Organization recommendations of > or =400 g/day for only 27% of all participating mothers. Based on both instruments, the Pro Children results showed comparatively high average fruit intake levels in Portugal, Denmark and Sweden (211, 203 and 194 g/day) and the lowest intake in Iceland (97 g/day). High vegetable intake levels were found in Portugal and Belgium (169 and 150 g/day), the lowest in Spain (88 g/day). A south-north gradient could not be observed in the Pro Children study. CONCLUSION: Fruit and vegetable intakes are low in mothers of 11-year-olds across Europe. Especially vegetable consumption can be regarded as marginal in most of the studied European countries. A high percentage of mothers indicated to eat fruit and vegetables less than once a day. The results have shown that national and international interventions are necessary to promote fruit and especially vegetable consumption in the European population of mothers.
Access to fruit and vegetables (FV) is associated with adolescents' FV consumption. However, little is known about implementation of strategies to increase access to FV at schools. We examined the implementation of two environmental components designed to increase access to FV at Danish schools.
We used data from 20 intervention schools involved in the school-based multicomponent Boost trial targeting 13-year-olds' FV consumption. The environmental components at school included daily provision of free FV and promotion of a pleasant eating environment. Questionnaire data was collected by the end of the nine-month intervention period among 1,121 pupils (95%), from all school principals (n?=?20) and half way through the intervention period and by the end of the intervention among 114 teachers (44%). The implementation of the components was examined descriptively using the following process evaluation measures; fidelity, dose delivered, dose received and reach. Schools with stable high implementation levels over time were characterised by context, intervention appreciation and implementation of other components.
For all process evaluation measures, the level of implementation varied by schools, classes and over time. Dose received: 45% of pupils (school range: 13-72%, class range: 7-77%) ate the provided FV daily; 68% of pupils (school range: 40-93%, class range: 24-100%) reported that time was allocated to eating FV in class. Reach: The intake of FV provided did not differ by SEP nor gender, but more girls and low SEP pupils enjoyed eating FV together. Dose delivered: The proportion of teachers offering FV at a daily basis decreased over time, while the proportion of teachers cutting up FV increased over time. Schools in which high proportions of teachers offered FV daily throughout the intervention period were characterized by being: small; having a low proportion of low SEP pupils; having a school food policy; high teacher- and pupil intervention appreciation; having fewer teachers who cut up FV; and having high implementation of educational components.
The appliance of different approaches and levels of analyses to describe data provided comprehension and knowledge of the implementation process. This knowledge is crucial for the interpretation of intervention effect.
Current Controlled Trials ISRCTN11666034.
Cites: Health Educ Behav. 2000 Apr;27(2):157-6610768797
Multi-component interventions which combine educational and environmental strategies appear to be most effective in increasing fruit and vegetable (FV) intake in adolescents. However, multi-component interventions are complex to implement and often poorly implemented. Identification of barriers and facilitators for implementation is warranted to improve future interventions.This study aimed to explore implementation of two intervention components which addressed availability and accessibility of FV in the multi-component, school-based Boost study which targeted FV intake among Danish 13-year-olds and to identify barriers and facilitators for implementation among pupils, teachers and FV suppliers.
We conducted focus group interviews with 111 13-year-olds and 13 teachers, completed class observations at six schools, and conducted telephone interviews with all involved FV suppliers. Interviews were transcribed, coded and analysed using qualitative analytical procedures.
FV suppliers affected the implementation of the FV programme at schools and thereby pupils' intake through their timing of delivery and through the quality, quantity and variety of the delivered FV. Teachers influenced the accessibility and appearance of FV by deciding if and when the pupils could eat FV and whether FV were cut up. Different aspects of time acted as barriers for teachers' implementation of the FV programme: time spent on having a FV break during lessons, time needed to prepare FV and time spent on pupils' misbehaviour and not being able to handle getting FV. Teacher timing of cutting up and serving FV could turn into a barrier for pupils FV intake due to enzymatic browning. The appearance of FV was important for pupils' intake, especially for girls. FV that did not appeal to the pupils e.g. had turned brown after being cut up were thrown around as a part of a game by the pupils, especially boys. Girls appreciated the social dimension of eating FV together to a larger extent than boys.
Limited time and pupils' misbehaviour were barriers for teachers' implementation. Establishing FV delivery to schools as a new routine challenged FV suppliers' implementation. Food aesthetics were important for most pupils' FV intake while the social dimension of eating FV together seemed more important to girls than boys.
Multi-component interventions combining educational and environmental strategies have proved effective in increasing children and adolescents' fruit and vegetable intake. However such interventions are complex and difficult to implement and several studies report poor implementation. There is a need for knowledge on the role of dose for behaviour change and for assessment of intervention dose to avoid conclusions that intervention components which are not implemented are ineffective. This study aimed to examine 1) the association between dose of a class curriculum and adolescents' fruit and vegetable intake in a school-based multi-component intervention, 2) if gender and socioeconomic position modify this association.
We carried out secondary analysis of data from intervention schools in the cluster-randomized Boost study targeting 13-year-olds' fruit and vegetable intake. Teacher- and student data on curriculum dose delivered and received were aggregated to the school-level and class-level (only possible for student data). We analysed the association between curriculum dose and students' (n 995) self-reported fruit and vegetable intake (24-h recall questionnaire) after finalization of the intervention using multi-level analyses. Potential moderation was examined by analyses stratified by gender and socioeconomic position.
Average dose received at class-level was significantly associated with students' fruit and vegetable intake (10 g (CI: 0.06, 20.33) per curricular activity received). In stratified analyses the association remained significant among boys only (14 g (CI: 2.84, 26.76) per curricular activity received). The average dose delivered and received at the school-level was not significantly associated with students' intake.
We found a dose-response relationship between number of curricular activities received and adolescents' fruit and vegetable intake. The results indicate that curriculum dose received only mattered for promotion of fruit and vegetable intake among boys. Future studies should explore this gender difference in larger samples to guide the planning of school-based curricular interventions with regards to the optimal number of curricular activities required to promote behavioural change in subgroups with low fruit and vegetable intake at baseline.
In multicomponent interventions it is important to examine the implementation of each component to enable valid assessments of the effectiveness of each component. Many studies do not systematically document, evaluate and report the level of implementation and there is a lack of systematic approaches to conduct process evaluation studies to guide researchers and evaluators. The aim of this study was to present a systematic approach to plan process evaluation of the implementation of randomised multicomponent interventions.
Building on existing process evaluation frameworks and concepts, we developed a six-step protocol: 1. Brainstorm of processes necessary for full implementation and potential barriers and facilitators to implementation; 2. Application of process evaluation concepts to ensure inclusion of important implementation processes; 3. Measurement of proximal outcomes; 4. Identification of relevant data sources; 5. Selection of methods and timing of data collection of process measures; 6. Development of instruments. The protocol was applied to the Boost study, a multicomponent school-based dietary intervention.
The protocol was readily applicable for planning process evaluation of environmental and educational intervention components in a school setting. The protocol ensures systematic assessment of the implementation processes that are crucial for interpretation of intervention effects.