***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: The energy density ( ED ; kcal/g ) of an entrée influences  children  's energy intake ( EI ) , but the effect of simultaneously changing both ED and portion size of an entrée on preschool children 's EI is unknown . In this within-subject crossover study , 3- to 5-year-old children ( 30 boys , 31 girls ) in a daycare facility were served a test lunch once/week for 4 weeks . The amount and type of vegetables and cheeses incorporated into the sauce of a pasta entrée were manipulated to create two versions that varied in ED by 25 % ( 1.6 or 1.2 kcal/g ) . Across the weeks , each version of the entrée was served to the children in each of two portion sizes ( 400 or 300 g ) . Lunch , consumed ad libitum , also included carrots , applesauce , and milk . Decreasing ED of the entrée by 25 % significantly ( P<0.0001 ) reduced children 's EI of the entrée by 25 % ( 63.1+/-8.3 kcal ) and EI at lunch by 17 % ( 60.7+/-8.9 kcal ) . Increasing the proportion of vegetables in the pasta entrée increased children 's vegetable intake at lunch by half of a serving of vegetables ( P<0.01 ) . Decreasing portion size of the entrée by 25 % did not significantly affect children 's total food intake or EI at lunch . Therefore , reducing the ED of a lunch entrée result ed in a reduction in  children 's EI from the entrée and from the meal in both portion size conditions . Decreasing ED by incorporating more vegetables into recipes is an effective way of reducing children 's  EI while increasing their vegetable intake BACKGROUND Whether large portion sizes affect children 's eating behavior has rarely been studied . OBJECTIVES Our objectives were 1 ) to determine the effects of repeated exposure to a large portion of an entrée on preschool-aged children 's awareness of portion size , self-selected portion size , and food intake and 2 ) to evaluate associations of children 's responsiveness to portion size with weight status and overeating . DESIGN Energy intake , bite size , and comments about portion size were evaluated among 30 children at 2 series of lunches in which either an age-appropriate portion or a large portion of an entrée was served . On separate occasions , the children 's self-served portions , weight , height , and tendency to overeat were assessed . RESULTS Doubling an age-appropriate portion of an entrée increased entrée and total energy intakes at lunch by 25 % and 15 % , respectively . Changes were attributable to increases in the average size of the children 's bites of the entrée without compensatory decreases in the intake of other foods served at the meal . These increases were seen even though observational data indicated that the children were largely unaware of changes in portion size . Greater responsiveness to portion size was associated with higher levels of overeating . The children consumed 25 % less of the entrée when allowed to serve themselves than when served a large entrée portion . CONCLUSIONS Large entrée portions may constitute an " obesigenic " environmental influence for preschool-aged children by producing excessive intake at meals . Children with satiety deficits may be most susceptible to large portions . Allowing children to select their own portion size may circumvent the effects of exposure to large portions on children 's eating OBJECTIVE : Large portions promote intake among children , but little is known about the external influences of the eating environment on children ’s self-selected portion sizes . This research experimentally tested effects of the amount of entree available and serving spoon size on children ’s self-served entree portions and intakes at dinner meals . A secondary objective was to identify  child and family predictors of self-served entree portion sizes . DESIGN : A 2 × 2 within-subjects design was used , in which the amount of a pasta entree available for self-serving ( 275 vs 550 g ) and the serving spoon size ( teaspoon vs tablespoon ) were systematic ally varied . The serving bowl size and portion sizes of all other foods offered were held constant across conditions . Conditions were spaced 1 week apart and r and omly assigned . Weighed  self-served entree portions and food intakes as well as demographics , maternal feeding styles and child/maternal anthropometrics were measured . SUBJECTS : Participants were 60 ethnically diverse children aged 4–6 years and their mothers . RESULTS : Mixed models revealed that children served themselves 40 % more entree when the amount available was doubled ( P<0.0001 ) and 13 % more when the serving spoon size was tripled ( P<0.05 ) . Serving spoon size and the amount of entree available indirectly influenced children ’s intake , with larger self-served portion sizes related to greater entree intakes ( P<0.0001 ) . Greater self-served portions and energy intakes at the meal were seen among those children whose mothers reported indulgent or authoritarian feeding styles ( P<0.001 ) . CONCLUSION : Children ’s self-served portion sizes at meals are influenced by size-related facets of the eating environment and reflect maternal feeding styles OBJECTIVE Determine the association of children 's susceptibility to large food portion sizes with appetite regulation and obesity . METHODS Normal-weight and obese non-Hispanic black children ( n = 100 ) aged 5 - 6 years were observed in four dinner conditions of varying portion size ; portions of all foods ( except milk ) offered were : 100 % ( 677 kcal ) , 150 % ( 1015 kcal ) , 200 % ( 1353 kcal ) , or 250 % ( 1691 kcal ) of those in the reference condition ( 100 % ) . Condition order was r and omly assigned to 2 - 4 children who ate together at each meal . Child height and weight were measured and caregiver reports of child appetite were obtained . Hierarchical growth curve models were used to estimate associations of meal energy intake with portion size condition , child weight status , and appetite regulation traits , controlling for demographics . RESULTS Total energy intake increased across conditions of increasing food portion size ( P < 0.001 ) . The effect of portion size condition on total energy intake varied with food responsiveness ( P = 0.05 ) and satiety responsiveness ( P < 0.05 ) , but not weight status ( P = 0.682 ) . Children with lower satiety responsiveness and greater food responsiveness showed greater increases in meal energy across conditions . CONCLUSIONS Children with poorer appetite regulation may be more vulnerable to obesogenic dietary environments offering large food portions than other children Large food portions may be facilitating excess energy intake ( EI ) and adiposity among adults . The present study aim ed to assess the extent to which EI and amounts of foods consumed are influenced by the availability of different-sized food portions . A r and omised within-subject cross-over , fully residential design was used , where forty-three ( twenty-one men and twenty-two women ) normal-weight and overweight adults were r and omly allocated to two separate 4 d periods where they were presented with either ' st and ard ' or ' large ' food portions of the same foods and beverages . The main outcome measures were the amount of food ( g ) and EI ( MJ ) consumed throughout each study period . Mean EI over 4 d was significantly higher on the large portion condition compared with the st and ard condition in the total group ( 59.1 ( sd 6.6 ) v. 52.2 ( sd 14.3 ) MJ ; P = 0.020 ) ; men and women increased their EI by 17 % ( 10 ( sd 6.5 ) MJ ; P < 0.001 ) and 10 % ( 4 ( sd 6.5 ) MJ ; P = 0.005 ) respectively when served the large food portions relative to the st and ard food portions . The increased intakes were sustained over the 4 d in the large portion condition with little evidence of down-regulation of EI and food intake being made by subjects . Increased food portion size result ed in significant and sustained increases in EI in men and women over 4 d under fully residential conditions . The availability and consumption of larger portions of food may be a significant factor contributing to excess EI and adiposity OBJECTIVE : To test the feasibility of creating a valid and reliable checklist with the following features : appropriate for assessing both r and omised and non-r and omised studies ; provision of both an overall score for study quality and a profile of scores not only for the quality of reporting , internal validity ( bias and confounding ) and power , but also for external validity . DESIGN : A pilot version was first developed , based on epidemiological principles , review s , and existing checklists for r and omised studies . Face and content validity were assessed by three experienced review ers and reliability was determined using two raters assessing 10 r and omised and 10 non-r and omised studies . Using different raters , the checklist was revised and tested for internal consistency ( Kuder-Richardson 20 ) , test-retest and inter-rater reliability ( Spearman correlation coefficient and sign rank test ; kappa statistics ) , criterion validity , and respondent burden . MAIN RESULTS : The performance of the checklist improved considerably after revision of a pilot version . The Quality Index had high internal consistency ( KR-20 : 0.89 ) as did the subscales apart from external validity ( KR-20 : 0.54 ) . Test-retest ( r 0.88 ) and inter-rater ( r 0.75 ) reliability of the Quality Index were good . Reliability of the subscales varied from good ( bias ) to poor ( external validity ) . The Quality Index correlated highly with an existing , established instrument for assessing r and omised studies ( r 0.90 ) . There was little difference between its performance with non-r and omised and with r and omised studies . Raters took about 20 minutes to assess each paper ( range 10 to 45 minutes ) . CONCLUSIONS : This study has shown that it is feasible to develop a checklist that can be used to assess the method ological quality not only of r and omised controlled trials but also non-r and omised studies . It has also shown that it is possible to produce a checklist that provides a profile of the paper , alerting review ers to its particular method ological strengths and weaknesses . Further work is required to improve the checklist and the training of raters in the assessment of external validity OBJECTIVE People eat more unhealthy foods when served more ( portion size effect ) and when the food is served in larger units ( unit size effect ) . The present study aim ed to examine whether these effects can be used for the good : to increase vegetable consumption  among children . DESIGN A 2 × 2 between-subjects experiment was conducted at two schools . Pupils were presented in class with cucumber that varied both in unit size ( one piece v. pre-sliced ) and portion size ( one-third v. two-thirds of a cucumber ) . Children ate ad libitum during the morning break and filled in a survey . SETTING Primary schools in the centre of the Netherl and s. SUBJECTS Primary -school pupils ( n 255 ) aged 8 - 13 years . RESULTS Children ate 54 % more cucumber  when served a large compared with a smaller portion ( difference of 49 g ; P<0·001 ) . Large units did not impact consumption ( P=0·58 ) , but were considered as less convenient to eat than small units ( P=0·001 ) . CONCLUSIONS Findings suggest that children 's vegetable intake can be improved by serving larger portions in smaller-sized pieces BACKGROUND Previous portion size research in children has focused on the impact of large entrée portions on children 's intake , but less attention has been given to how intake at a meal is affected across a broader range of entrée portions . OBJECTIVE The objective was to assess the effect of serving a range of entrée portions on children 's ad libitum intake and energy density consumed at the meal . DESIGN A within-subject design was used to examine the effect of varying entrée portions ( ie , 100 , 160 , 220 , 280 , 340 , and 400 g ) on children 's ad libitum energy intake of macaroni and cheese and fixed portions of unsweetened applesauce , green beans , and whole-wheat roll served with the entree .  Seventeen children ( 10 girls ) , aged 3 to 6 y , were served a series of 6 lunches , which varied only in entrée portion size , once per week . Weight , height , and weighed food intake were measured . RESULTS Increasing portion size increased children 's entrée intake ( P < 0.01 ) and decreased intake of other foods served with the entrée , including fruit and vegetables ( P < 0.0001 ) . As a result , children consumed a more-energy-dense ( kcal/g ) lunch as portion size increased ( P < 0.0001 ) . Further examination showed that BMI percentile moderated the positive association between portion size and entrée intake ( P < 0.01 ) ; overweight children showed greater increases in entree intake with increasing entrée portion . CONCLUSION Serving smaller age-appropriate entrée portions may be one strategy to improve children 's nutritional profile by decreasing intake of energy-dense foods and by promoting intake of fruit and vegetables served with the entree OBJECTIVE We tested the effect on energy intake of increasing the portion size of all foods and beverages served over 2 consecutive days . DESIGN The study used a r and omized crossover design . SUBJECTS/ SETTING Subjects were 32 adults from a university community . INTERVENTION For 2 consecutive days in each of 3 weeks , 
    Output:
    
The PSE was demonstrated in children aged 2 - 12 years when offered both unit and amorphous food items .
The effect was not restricted by food type , child age or influenced by initial portion size served .