Food and Nutrition Bulletin Volume 17, Number 3, 1996 (UNU Food and Nutrition Bulletin, 1996, 104 pages) 
Nutrition and behaviour 
Effects of breakfast on classroom behaviour in rural Jamaican schoolchildren 

The initial observation sample was 120 children. Seven children were lost from the study, and the resulting sample consisted of 57 undernourished and 56 adequately nourished children.
The children's anthropometry and social background are shown in table 4. As would be expected from the selection criteria, the undernourished children were significantly smaller in all anthropometric measures than the adequately nourished children. The mean age of the undernourished children was six months greater than that of the adequately nourished children (p < .01) and they had fewer schoolbooks (p < .05). The other two socioeconomic ratings were not significantly different in undernourished and adequately nourished children.
TABLE 4. Anthropometric and socioeconomic characteristics of children according to nutritional status
Characteristic  Nutritional status  
Undernournished (29 M, 28 F)  Adequately
nourished (28 M, 28 F)  
Mean  SD  Mean  SD  
Age (yr)  9.68  0 42  9.18  0.77** 
Heightforage (zscore)  1.30  0.54  0.58  0.91*** 
Weightforage (zscore)  1.56  0.28  0.30  0.56* * * 
BMI (kg/m²)  14.43  0.92  16.45  1.50** 
Book score  4.61  3.75  6.28  3 87* 
Housing score (08)  2.67  1.86  3.00  1.89 
Uniform score (04)  2.93  1.08  3.23  0.97 
*p < .05, **p < .01, ***p < .001 by Student's retest.
The correlations among the behaviours summed over four days were examined for the teaching and set task situations separately. In the teaching situation, children who were more on task participated more (r= .72, p < .001), and spoke (r= .48, p < .001) and moved (r= .21, p < .05) less, than children who were less on task. Children who talked more also moved more (r = .25, p < .01) and participated less (r= .20, p < .05). During the set task situation, the children who were less on task talked more (r = .65, p < .001) and moved more (r = .28, p < .01). Also, as they talked more, they moved around more (r = .40, p < .001).
Correlations were calculated between the behaviours summed over the four days and the anthropometric measures and age. In the teaching situation there were no significant associations between the behaviours and the anthropometric measures and age. In the set task situation there was a significant positive correlation between attention to task and the children's heightforage (p < .05) and BMI (p < .05) (table 5). There were significant negative associations between all three anthropometric measures and gross motor behaviour in the set task situation (p < .05). Thus, children with poorer nutritional status tended to move more at their desks and in the classroom when left to work on their own. When the adequately nourished and undernourished groups were considered separately, the same pattern of correlations was observed in the adequately nourished children but not in the undernourished children. It is possible that the restricted range of nutritional status accounted for the latter finding.
TABLE 5. Pearson productmoment correlations (r) of behaviours over four days in the set task situations with anthropometry and age on enrollment
Behaviour  Heightforage  Weightforage  BMI 
ON TASK  .16*  .14  .16* 
TALKS  .07  .05  .12 
GROSS MOTOR  .18*  .21*  .17* 
*p < .05.
The effect of nutritional status was further examined in a repeatedmeasures analysis of variance, with the behaviours with and without breakfast as the withinsubject factor and nutritional group as the betweensubject factor. There were no main effects of nutritional group on any of the behaviours in the teaching situations. However, in the set task situation there was a nutritional group effect on gross motor behaviour (F = 4.31, p < .05), with the undernourished group moving more often.
The frequencies with which the behaviours occurred in the teaching and set task situations are shown in tables 6 and 7. Repeatedmeasures analyses of variance for each behaviour, using behaviour with and without breakfast as the withinsubject factor and school, sex, and nutritional group as the betweensubject factors, were calculated for the two types of situations separately. In the set task situation, girls talked more (F = 6.90, p < .05) and had more gross motor activity (F = 6.23, p < .05) than boys. There were no significant interactions between sex and treatment. There were also no significant main effects of nutritional group or treatment on any of the classroom behaviours and no significant interactions between nutritional group and treatment in these analyses.
TABLE 6. Unadjusted medians and ranges of frequency of behaviours with and without breakfast in the teaching situation by school (undernourished and adequately nourished groups combined)
Behaviour by school  Breakfast  No breakfast^{a} 
School SV (n = 24)  
ON TASK  151.3 (18.0)^{b}  137.3 (28.0)^{b} 
TALKS  4 (031)  6 (132) 
GROSS MOTOR  8 (036)  14 (160) 
PARTICIPATE/RESPONSE  45 (15109)  49 (687) 
School Ml (n = 22)  
ON TASK  123.2 (31.5)^{b}  128.5 (32.8)^{b} 
TALKS  13 (138)  7 (122) 
GROSS MOTOR  7 (117)  8 (216) 
PARTICIPATE/RESPONSE  37 (2 86)  34 (6139) 
School GH (n = 18)  
ON TASK  125.9 (39.6)^{b}  137.4 (34.2)^{b} 
TALKS  15 (5 41)  12 (034) 
GROSS MOTOR  13 (340)  12 (242) 
PARTICIPATE/RESPONSE  47 (1683)  43 (13101) 
School AR (n = 49)  
ON TASK  129.3 (27.0)^{b}  131.1 (28.2)^{b} 
TALKS  12 (059)  12 (074) 
GROSS MOTOR  9 (134)  8 (120) 
PARTICIPATE/RESPONSE  37 (8143)  31 (6112) 
a. Children given onequarter of an orange.
b. Mean (SD) number of 10second periods "on tasks".
There were however, significant school effects and schooltreatment interactions in both situations, indicating that the treatment affected children differently in the different schools. In the teaching situation there was a significant interaction effect in "on task" (F = 4.43, p < .01), "talks" (F = 3.33, p < .05) and "gross motor" behaviours (F = 2.71, p < .05). In the set task situation, there was a significant schooltreatment interaction in the "on task" behaviour (F = 5.71, p < .001).
TABLE 7. Unadjusted medians and ranges of frequency of behaviours with and without breakfast in the set task situation by school (undernourished and adequately nourished groups combined)
Behaviour by school  Breakfast  No breakfast^{a} 
School SV (n = 24)  
ON TASK  143.1 (20.2)^{b}  134.6 (30.9)^{b} 
TALKS  16 (171)  15 (471) 
GROSS MOTOR  11 (133)  10 (350) 
School Ml (n = 22)  
ON TASK  121.1 (29.5)^{b}  136.4 (23.4)^{b} 
TALKS  25 (166)  19 (754) 
GROSS MOTOR  6 (015)  6 (017) 
School GH (n = 18)  
ON TASK  119.4 (22.8)^{b}  135.4 (16.5)^{b} 
TALKS  33 (1086)  24 (465) 
GROSS MOTOR  9 (225)  7 (128) 
School AR (n = 49)  
ON TASK  118.0 (22.7)^{b}  112.9 (27.6)^{b} 
TALKS  34 (399)  32 (3103) 
GROSS MOTOR  9 (025)  10 (147) 
a. Children given onequarter of an orange.
b. Mean (SD) number of 10second periods "on task."
Postanalysis of variance comparisons showed that during the teaching situation, the children's attention to task in school SV increased significantly with breakfast (t = 2.89, p < .01; see