The original you to definitely integrated brand new health quality of items, gender, amounts and you can a varying denoting nutritional position (overweight/obesity=Body mass index Z-get ?+1)

All universities had been classified from the Chilean Ministry from Training for the about three accounts, namely lowest-finding colleges, mid-achieving colleges and you will high-gaining universities, reliant the fresh new abilities of the students in most SIMCE testing ( thirty-two ) .

Anthropometric measurements and you may nutritional condition

Standardized procedures were used to measure students’ weight to the nearest 0·1 kg, using a Seca scale (SECA, Hamburg, Germany), and height to the nearest 0·1 cm, using a Holtain stadiometer. All instruments were verified before measuring each participant ( Reference Gibson 33 ) . BMI (kg/m 2 ) and height-for-age were evaluated, and Z-scores were obtained according to the references of the Centers for Disease Control, National Center for Health Statistics (USA) ( Reference Kuczmarski, Ogden and Guo 34 ) . Nutritional status was defined as follows: underweight, BMI Z-score

Socio-financial standing

Socio-monetary status (SES) are measured playing with a scale centered on Graffar’s altered strategy and therefore are adjusted so you can Chilean urban and you can rural populations ( Resource Alvarez, Muzzo and you may Ivaple on four socio-financial organizations: 1=higher (0·3 %); 2=mid–high (14·seven %); 3=middle (step 38·3 %); 4=mid–lower (45·six %); and you will 5=low (step one·step 1 %). Although not, inside our research i combined these four categories on the around three: high (1+2), center (3) and reasonable (4+5) SES.

Statistical research

Statistical analysis included performing ? 2 tests to compare categorical variables, and ANOVA and Bonferroni tests for comparison of continuous variables. After performing bivariate analyses with each potential confounding variable, including sex, grade, nutritional status, SES and school’s performance, we used logistic regression to assess the relationship between the nutritional quality of snacks at school (exposure) and individual academic performance in Mathematics and Language (outcome). In each case, the probability of passing the test was estimated using three models. In the second model, SES was added. Finally, a fully adjusted model contained all mentioned covariates with the addition of a variable denoting the school’s academic performance. Because the variable school’s performance was partly derived from the outcome variables, this adjustment may cause underestimation of the association, so we included models with and without adjustment for school’s performance. A P value of <0·05 denoted statistical significance. Data were processed using the statistical software package Stata SE for Windows version 12·0.


Our try was developed right up away from thirteen·1 ( sd 2·3) year-dated men (52 %) and females (forty eight %) teenagers out of reasonable (44·3 %), center (39·6 %) and high (16·step one %) SES. It attended 5th (51·nine %) and 9th (48·step one %) values in public (34·8 %), partially sponsored (57·8 %) and private colleges (7·cuatro %) throughout the Santiago Urban Area. As for nutritional reputation, 45 % away from members was in fact obese or overweight. Almost 1 / 2 of the young (48 %) attended highest-achieving schools, whereas 31 % and you will 23 % attended mid- and you will reduced-finding schools, respectively.

From the try, 56 % out of college students stated usage of items within treat big date that were filled up with fat, glucose, salt and energy. Thirty-half dozen per cent had been regarded to have terrible-to-reasonable snacking, while simply 8 % was basically thought to eat fit items for the snack time on university. Table step one gets the descriptive statistics of one’s test. Average philosophy off score for the Words and you will Math was in fact significantly ong people who have all the way down health quality of dinners in school (P=0·01). The share out of children consuming substandard dinners at school are significantly large among 9th graders (59 %; P=0·040), pupils likely to reduced-reaching universities (61 %; P=0·036), together with one of skinny and normal-pounds participants (69 % and 62 %, respectively; P=0·006).