Changes in the nutritional content of children's lunches after the Food Dudes healthy eating programme.

Previous research into the effectiveness of healthy eating programmes has shown increases in healthful eating behaviour in primary schools; however, data collection methods have not been sufficiently sensitive to detect micronutrient changes. The present study extends the literature by measuring individual children's intake of macro- and micronutrients at lunchtime, before and after a programme targeting children's consumption of fruit and vegetables, to identify evidence-based health benefits of programme participation. Baseline data were collected over 4 d at lunchtime in two primary schools. The Food Dudes programme was then implemented in the intervention school. Follow-up data were collected over 4 d in each school 2 months after baseline. We employed a validated and sensitive photographic method to estimate individual children's (N 112) consumption of fruit, vegetables, and their intake of calories, macro- and selected micronutrients. Significant changes were observed in the intervention school but not in the control school: Children's consumption of fruit, vegetables, vitamin C and E intake increased, while their total energy consumption, fat, saturated fat, and sodium intake decreased. The present results show that the Food Dudes programme produced a positive nutritional change, with implications for its application as a healthy eating and obesity prevention intervention. These optimistic conclusions should be tested by further research to establish the longevity of the positive effects presented here.

Using Nudges to Promote Healthy Food Choices in the School Dining Room: A Systematic Review of Previous Investigations.

BACKGROUND: There is a growing interest in low-cost interventions that modify obesogenic environments and encourage positive behavior change. We conducted a systematic review of studies that used behavioral nudges to promote a healthy school cafeteria environment. METHODS: A literature search was conducted using 5 databases; of 381 papers noted, we included 25 and assessed them using the Quality Assessment Tool for Quantitative Studies. RESULTS: Most studies used relatively small, convenience samples and data collection methods that could not be described as robust, necessitating cautious interpretation of their results. A range of behavioral nudges were employed. Seventeen studies reported positive effects on children's selection and 11 studies reported improvements in their consumption of target foods, effected by changing the order of serving; increasing the convenience, attractiveness, and normativeness of selecting healthy options; increasing the variety available; and attractive target food labeling. CONCLUSIONS: Overall, this review identified the requirement for well-designed and well-controlled investigations into the effects of changing the choice architecture in school cafeterias, assessing short-, medium-, and long-term changes in individual children's consumption, utilizing validated measures, and conducted across a variety of settings, including dining rooms of schools outside the United States.

Measuring lunchtime consumption in school cafeterias: a validation study of the use of digital photography.

OBJECTIVE: The present study tested the validity of a digital image-capture measure of food consumption suitable for use in busy school cafeterias. DESIGN: Lunches were photographed pre- and post-consumption, and food items were weighed pre- and post-consumption for comparison. SETTING: A small research team recorded children's lunchtime consumption in one primary and one secondary school over seven working days.ParticipantsA primary-school sample of 121 children from North Wales and a secondary-school sample of 124 children from the West Midlands, UK, were utilised. Nineteen children were excluded because of incomplete data, leaving a final sample of 239 participants. RESULTS: Results indicated that (i) consumption estimates based on images were accurate, yielding only small differences between the weight- and image-based judgements (median bias=0·15-1·64 g, equating to 0·45-3·42 % of consumed weight) and (ii) good levels of inter-rater agreement were achieved, ranging from moderate to near perfect (Cohen's κ=0·535-0·819). This confirmed that consumption estimates derived from digital images were accurate and could be used in lieu of objective weighed measures. CONCLUSIONS: Our protocol minimised disruption to daily lunchtime routine, kept the attrition low, and enabled better agreement between measures and raters than was the case in the existing literature. Accurate measurements are a necessary tool for all those engaged in nutrition research, intervention evaluation, prevention and public health work. We conclude that our simple and practical method of assessment could be used with children across a range of settings, ages and lunch types.

A low-cost Behavioural Nudge and choice architecture intervention targeting school lunches increases children's consumption of fruit: a cluster randomised trial.

BACKGROUND: Research has consistently indicated that most children do not consume sufficient fruit and vegetables to provide them with a healthy, balanced diet. This study set out to trial a simple, low-cost behavioural nudge intervention to encourage children to select and consume more fruit and vegetables with their lunchtime meal in a primary school cafeteria. METHODS: Four primary schools were randomly allocated to either the control or the intervention condition and baseline data were collected over two days in each school. Following this, changes were made to the choice architecture of the school cafeterias in the intervention schools and maintained over a three-week period. The intervention included improved positioning and serving of fruit, accompanied by attractive labelling of both fruit and vegetables on offer. Next, data were collected over two days in each school, with menus matched in each instance between baseline and follow-up. We employed a validated and sensitive photographic method to estimate individual children's (N = 176) consumption of vegetables, fruit, vitamin C, fibre, total sugars, and their overall calorie intake. RESULTS: Significant increases were recorded in the intervention schools for children's consumption of fruit, vitamin C, and fibre. No significant changes were observed in the control condition. The increases in fruit consumption were recorded in a large proportion of individual children, irrespective of their baseline consumption levels. No changes in vegetable consumption were observed in either condition. CONCLUSIONS: These results are the first to show that modest improvements to the choice architecture of school catering, and inclusion of behavioural nudges, can significantly increase fruit consumption, rather than just selection, in primary-age children. This has implications for the development of national and international strategies to promote healthy eating in schools. TRIAL REGISTRATION: AsPredicted: 3943 05/02/2017. URL: https://aspredicted.org/see_one.php?a_id=3943.

Validity and reliability of the Fitbit Zip as a measure of preschool children's step count.

OBJECTIVES: Validation of physical activity measurement tools is essential to determine the relationship between physical activity and health in preschool children, but research to date has not focused on this priority. The aims of this study were to ascertain inter-rater reliability of observer step count, and interdevice reliability and validity of Fitbit Zip accelerometer step counts in preschool children. METHODS: Fifty-six children aged 3-4 years (29 girls) recruited from 10 nurseries in North Wales, UK, wore two Fitbit Zip accelerometers while performing a timed walking task in their childcare settings. Accelerometers were worn in secure pockets inside a custom-made tabard. Video recordings enabled two observers to independently code the number of steps performed in 3 min by each child during the walking task. Intraclass correlations (ICCs), concordance correlation coefficients, Bland-Altman plots and absolute per cent error were calculated to assess the reliability and validity of the consumer-grade device. RESULTS: An excellent ICC was found between the two observer codings (ICC=1.00) and the two Fitbit Zips (ICC=0.91). Concordance between the Fitbit Zips and observer counts was also high (r=0.77), with an acceptable absolute per cent error (6%-7%). Bland-Altman analyses identified a bias for Fitbit 1 of 22.8±19.1 steps with limits of agreement between -14.7 and 60.2 steps, and a bias for Fitbit 2 of 25.2±23.2 steps with limits of agreement between -20.2 and 70.5 steps. CONCLUSIONS: Fitbit Zip accelerometers are a reliable and valid method of recording preschool children's step count in a childcare setting.

Validation of food diaries as measures of dietary behaviour change.

This study aimed to validate the ability of a 24-h food diary (the DIET-24) to accurately detect change in children's fruit and vegetable consumption at school snack time following implementation of the Food Dudes healthy eating intervention. Participants were 4- to 9-year-old children from two primary schools in England. There were 148 participants in the intervention school and 43 participants in the no intervention control school. For each child, snack-time fruit and vegetable consumption was measured separately by weight (grammes), and compared with teachers' estimates (to the nearest half portion) using the DIET-24. Both consumption measures were taken at T1 (pre-intervention) and T2 (post-intervention). At each time-point, Spearman rank correlations between the two measures were low to moderate, but significant. However, when compared with weighed measures, the DIET-24 did not always accurately detect significant changes in children's fruit and vegetable consumption following the intervention. To provide sensitive measures of behaviour change, it is important that dietary measures assess as accurately as possible the amount of food consumed, rather than, as is often the case, rely on all-or-none portion estimates. This issue is important for the establishment of a reliable evidence-base for healthy eating interventions.

The impact of body-part-naming training on the accuracy of imitative performances in 2- to 3-year-old children.

A series of three experiments explored the relationship between 3-year-old children's ability to name target body parts and their untrained matching of target hand-to-body touches. Nine participants, 3 per experiment, were presented with repeated generalized imitation tests in a multiple-baseline procedure, interspersed with step-by-step training that enabled them to (i) tact the target locations on their own and the experimenter's bodies or (ii) respond accurately as listeners to the experimenter's tacts of the target locations. Prompts for on-task naming of target body parts were also provided later in the procedure. In Experiment 1, only tact training followed by listener probes were conducted; in Experiment 2, tacting was trained first and listener behavior second, whereas in Experiment 3 listener training preceded tact training. Both tact and listener training resulted in emergence of naming together with significant and large improvements in the children's matching performances; this was true for each child and across most target gestures. The present series of experiments provides evidence that naming--the most basic form of self-instructional behavior--may be one means of establishing untrained matching as measured in generalized imitation tests. This demonstration has a bearing on our interpretation of imitation reported in the behavior analytic, cognitive developmental, and comparative literature.

Comprehension and production of body part labels in 2- to 3-year-old children.

This study examined which body part labels children could (i) produce when the experimenter touched different locations on her own body, asking each time 'What's this?' and (ii) comprehend by touching the correct locations on their own bodies in response to the experimenter asking 'Where's the [body-part label]?'. Seventeen children aged between 26 and 41 months, tested in a repeated measures procedure, were presented with 50 different body part stimuli in 200 test trials per child. Overall, the children produced fewer body part labels than they could comprehend. The accuracy of children's responses depended on (i) the location or extent of each body part (facial and broad body features were better known; joints and features in or attached to broad body parts the least well known); (ii) the amount of sensory (but not motor) representation each body part has in the human cortex; and (iii) whether a body part was commonly named by caregivers. These results present a precise mapping of the body parts that young children are able to name and locate on their own bodies in response to body part names; they suggest several possible determinants of lexical-semantic body knowledge and add to the understanding of how it develops in childhood.

Rapid word learning in 13- and 17-month-olds in a naturalistic two-word procedure: looking versus reaching measures.

This study investigated infants' rapid learning of two novel words using a preferential looking measure compared with a preferential reaching measure. In Experiment 1, 21 13-month-olds and 20 17-month-olds were given 12 novel label exposures (6 per trial) for each of two novel objects. Next, in the label comprehension tests, infants were shown both objects and were asked, "Where's the [label]?" (looking preference) and then told, "Put the [label] in the basket" (reaching preference). Only the 13-month-olds showed rapid word learning on the looking measure; neither age group showed rapid word learning on the reaching measure. In Experiment 2, the procedure was repeated 24h later with 10 participants per age group from Experiment 1. After a further 12 labels per object, both age groups now showed robust evidence of rapid word learning, but again only on the looking measure. This is the earliest looking-based evidence of rapid word learning in infants in a well-controlled (i.e., two-word) procedure; our failure to replicate previous reports of rapid word learning in 13-month-olds with a preferential reaching measure may be due to our use of more rigorous controls for object preferences. The superior performance of the younger infants on the looking measure in Experiment 1 was not straightforwardly predicted by existing theoretical accounts of word learning.

Increasing pre-school children's consumption of fruit and vegetables. A modelling and rewards intervention.

Using a repeated measures design, in a nursery setting, a modelling and rewards intervention targeted preschool children's consumption of 8 fruit and 8 vegetables (presented as 4 different food sets, each comprising 2 fruit and 2 vegetables). During the 16-day Baseline 1, and subsequent baselines, the children received a different food set daily, first at snacktime and again at lunchtime; consumption of these foods was not rewarded. In the 32-day fruit intervention phase, Food Set 2 and Food Set 3 were presented on alternate days; rewards were presented only at snacktime, and only for consumption of the fruit components. Following Baseline 2 and Baseline 3, the intervention targeted snack consumption of the vegetable components of Food Sets 1 and 4. Finally, Baseline 4, and 6-month Follow up were conducted. The interventions produced large and significant increases in target fruit and vegetable consumption with smaller, but significant, increases for the paired, opposite category, non-target foods. Immediately after each intervention, increases based on within-category generalisation were also evident. All increases generalised strongly to the no-rewards lunchtime context. Contrary to theories predicting response decrements, the increases in preschoolers' fruit and vegetable consumption were maintained at Follow up, six months after rewards were withdrawn.

Effects of rewards, peer-modelling and pedometer targets on children's physical activity: a school-based intervention study.

This study evaluated a physical activity intervention for children that comprised peer-modelling, pedometer step goals and tangible rewards. A version of the intervention without the reward component was also tested. Participants (n = 386) were from three primary schools, which were randomly assigned to one of three conditions: (i) full intervention, where children received "Fit 'n' Fun Dude" peer-modelling materials and were given daily pedometer goals to receive rewards, (ii) no-rewards intervention, where children received peer-modelling materials and pedometer goals but rewards were not used and (iii) control, where children wore pedometers with no further intervention. Physical activity was measured at baseline, intervention and at the end of a 14-week 'taper' phase. During the intervention, the full intervention school showed the largest increase in physical activity relative to baseline (+2456 steps per day, p < 0.001). There was a smaller increase in the no-rewards school (+1033 steps per day, p < 0.03), and no significant change in the control. At the end of the taper phase, physical activity in the no-rewards school continued to increase (+2030 steps per day, p < 0.001) but had returned to baseline in the full intervention school. The intervention that used only peer-modelling and pedometer goals produced better effects over time.

Do infants show generalized imitation of gestures? II. The effects of skills training and multiple exemplar matching training.

The determinants of generalized imitation of manual gestures were investigated in 1- to 2-year-old infants. Eleven infants were first trained eight baseline matching relations; then, four novel gestures that the infants did not match in probe trials were selected as target behaviors. Next, in a generalized imitation test in which matching responses to baseline models were intermittently reinforced, but matching responses to target models were not eligible for reinforcement, the infants matched baseline models but not the majority of their target behaviors. To ensure their failure to match the target behaviors was not due to motor constraints, the infants were trained, in a multiple-baseline procedure, to produce the target responses under stimulus control that did not include an antecedent model of the target behavior. There was no evidence of generalized imitation in subsequent tests. When the infants were next trained to match each target behavior to criterion (tested in extinction) in a multiple-baseline-across-behaviors procedure, only 2 infants continued to match all their targets in subsequent tests; the remaining infants matched only some of them. Seven infants were next given mixed matching training with the target behaviors to criterion (tested in extinction); they subsequently matched these targets without reinforcement when interspersed with trials on which matching responses to baseline models were intermittently reinforced. In repeat tests, administered at 3-week intervals, these 7 children (and 2 that did not take part in mixed matching training) continued to match most of their target behaviors. The results support a trained matching account, but provide no evidence of generalized imitation, in 1- to 2-year-old infants.

The effects of modelling, local stimulus enhancement, and affordance demonstration on the production of object-directed actions in 6-month-old infants.

The present study investigated whether local stimulus enhancement and the demonstration of objects' affordances--both of which are inherent in modelling of object-directed target actions--are themselves sufficient to evoke the target behaviour on imitation test trials. Six-month-old infants were presented with a puppet wearing a removable mitten and observed either a demonstration of mitten removal (modelling group), the experimenter pointing at the mitten (stimulus enhancement group), the mitten falling off apparently by itself (affordance demonstration group), or no specific action directed at the mitten (control group). For all infants, the puppet was next presented without any accompanying demonstrations and infants' mitten removal behaviours in the response period were recorded. The results showed that local stimulus enhancement and affordance demonstration were as effective as full modelling in evoking the target action. This finding shows that the performances of 6-month-old infants on imitation tests can be multiply determined and evoked by variables other than modelling of target behaviour.

Positive- and negative peer modelling effects on young children's consumption of novel blue foods.

OBJECTIVE: The effects of positive- and negative peer modelling on children's consumption of a novel blue food, presented in each of four snack meals during an "activity" day, were evaluated. It was predicted that: (i) novel food consumption would increase after positive modelling, but decrease after negative modelling; (ii) modelling effects would generalise to a second novel blue food when participants were alone when they ate their snack; (iii) that positive modelling would reverse the effects of negative modelling. DESIGN: A mixed design was employed with random assignment to either Groups A, B, or C (equal numbers of males and females per group). Within groups, each participant received the novel food on four snack occasions. Group A received positive modelling of blue food consumption on the first and third occasions, but were alone when they received the foods on the second and fourth occasions; Group B had negative modelling on the first occasion, positive modelling on the third, and ate alone on the second and fourth; Group C ate alone on all four occasions. To measure generalisation, an additional blue food was presented in all second and fourth "alone" occasions. PARTICIPANTS: Thirty-five 5-7-year olds took part in Study 1, and 44 3-4-year olds in Study 2. RESULTS: All main predictions were confirmed except that positive peer modelling did not reverse the effects of negative modelling in the 3-4-year olds. CONCLUSION: Negative peer modelling inhibits novel food consumption, and its effects are particularly difficult to reverse in younger children.

Determinants of imitation of hand-to-body gestures in 2- and 3-year-old children.

Twenty children, ten 2-year-olds and ten 3-year-olds, participated in an AB procedure. In the baseline phase, each child was trained the same four matching relations to criterion under intermittent reinforcement. During the subsequent imitation test, the experimenter modeled a total of 20 target gestures (six trials each) interspersed with intermittently reinforced baseline trials. In each session, target gestures were selected in a pre-randomized sequence from: Set 1--ear touches; Set 2--shoulder touches; Set 3--midarm touches; and Set 4--wrist touches; subjects' responses to targets were not reinforced. In each target set, half the gestures featured in nursery matching games and were termed common targets whereas the remainder, which were topographically similar but did not feature in the games, served as uncommon targets. The children produced significantly more matching responses to common target models than to uncommon ones. Common responses were also produced as mismatches to uncommon target models more often than vice versa. Response accuracy did not improve over trials, suggesting that "parity" did not serve as a conditioned reinforcer. All children showed a strong bias for "mirroring"--responding in the same hemispace as the modeler. The 2-year-olds produced more matching errors than the 3-year-olds and most children showed a bias for responding with their right hands. The strong effects of training environment (nursery matching games) are consistent with a Skinnerian account, but not a cognitive goal theory account, of imitation in young children.

Naming and categorization in young children: v. manual sign training.

Following pre-training with everyday objects, 8 children aged from 2 to 4 years learned to produce one manual sign (fists placed one above the other, in front of body) to one stimulus and an alternative manual sign (shoulders touched with ipsilateral hands) to the other stimulus, with each of three pairs of different arbitrary wooden shapes (Set 1). The six stimuli then were presented in category match-to-sample tests, which all subjects passed. Three of the children were next trained to produce the manual signs (denoted as fist/shoulder) for an additional six arbitrary stimuli, Set 2. All 3 children went on to pass category match-to-sample tests for Set 2, and for Set 1 and Set 2 combined. In the final experimental phase, 2 of the children were trained, for one of the six stimulus pairs, to produce the vocal tact "zag" to one stimulus and "vek" to the other. Both children showed category transfer of these vocalizations in test trials with each of the remaining five stimulus pairs, and all the stimuli combined in a 12-stimulus array. In line with Horne and Lowe's (1996) naming account, manual sign naming was found to be as effective as vocal naming in establishing arbitrary stimulus categorization, measured in terms of category sorting and transfer of function. The findings also have implications for the training of verbal repertoires in people with learning disabilities.

Do infants show generalized imitation of gestures?

Two experiments were conducted to investigate generalized imitation of manual gestures in 1- to 2-year-old infants. In Experiment 1, 6 infants were first trained four baseline matching relations (e.g., when instructed "Do this", to raise their arms after they saw the experimenter do so). Next, four novel gestures that the infants did not match in probe trials were selected as target behaviors during generalized imitation Test 1; models of these gestures were presented on unreinforced matching trials interspersed with intermittently reinforced baseline matching trials. None of the infants matched the target behaviors. To ensure that these behaviors were in the infants' motor skills repertoires, the infants were next trained to produce them, at least once, under stimulus control that did not include an antecedent model of the target behavior. In repeat generalized imitation trials (Test 2), the infants again failed to match the target behaviors. Five infants (3 from Experiment 1) participated in Experiment 2, which was identical to Experiment 1 except that, following generalized imitation Test 1, the motor-skills training was implemented to a higher criterion (21 responses per target behavior), and in a multiple-baseline, across-target-behaviors procedure. In the final generalized imitation test, 1 infant matched one, and another infant matched two target behaviors; the remaining 17 target behaviors still were not matched. The results did not provide convincing evidence of generalized imitation, even though baseline matching was well maintained and the target behaviors were in the infants' motor skills repertoires, raising the question of what are the conditions that reliably give rise to generalized imitation.