Chilean reference of length at birth.

BACKGROUND: To generate a reference of length at birth (LB) according to sex and gestational age (GA) of the Chilean population. METHODS: This cross-sectional observational study used public pooled Chilean newborn (NB) population data registered by the Civil Registry and Identification Service in Chile from 2000 to 2016. Multiple births, entries without information for LB, GA, and sex, and birth lengths <-4SD and > 4SD, were excluded. After applying the selection and randomization criteria, the final sample was made up of 5 010 963 NB (2 560 310 boys; 2 450 653 girls). Length at birth centiles by sex and GA (24-42 weeks) were calculated using the GAMLSS method and then compared with the INTERGROWTH-21st standard. RESULTS: Girls had a lower LB than boys. For most GA and in both sexes, the absolute and percentage differences of percentiles as compared with INTERGROWTH-21st were lower than 1 cm and 1%, respectively. CONCLUSIONS: We present a reference for LB by sex and GA in the Chilean population, developed following updated methodological criteria for neonatal anthropometry, which is acceptably consistent with the INTERGROWTH-21st standard. The reference we propose may be used in clinical and epidemiological studies to identify either Chilean individuals or populations, respectively, at higher risk of perinatal and infant adverse events related to LB.

Referencias de índice de masa corporal. Precisión diagnóstica con área grasa braquial en escolares argentinos / Body mass index references. Diagnostic accuracy with the upper-arm fat area in Argentine schoolchildren

El índice de masa corporal (IMC) es una eficaz herramienta para detectar la sobrecarga ponderal en niños y adolescentes, asociado a la adiposidad corporal. Objetivo. Analizar la concordancia, sensibilidad y especificidad de tres referencias internacionales de IMC/edad (OMS, IOTF y CDC) para diagnosticar el exceso ponderal y conocer su precisión diagnóstica para identificar el exceso de adiposidad con relación al área grasa braquial (AGB) en población infanto juvenil de Argentina. Materiales y métodos. Se realizó un estudio multicéntrico, descriptivo-comparativo y transversal entre 2003 y 2008, en 22.658 niños y adolescentes argentinos de 4 a 13 años de edad. A partir del peso, talla, circunferencia del brazo y pliegue tricipital, se calcularon IMC y AGB. Se analizó la concordancia, sensibilidad y especificidad de referencias de IMC/edad (OMS, CDC, IOTF) y la precisión diagnóstica (curvas ROC) para identificar exceso de adiposidad, a partir del AGB, así como el punto de corte óptimo (PCO). Resultados. Las tres referencias tuvieron buena concordancia. La mayor sensibilidad correspondió a OMS y la mayor especificidad a IOTF. El área bajo la curva (ABC) fue mayor en Z-IMC/IOTF en varones y en Z-IMC/OMS en mujeres. Los PCO mostraron discrepancias, siendo mayores con OMS. Conclusión. Las tres referencias muestran similar precisión diagnóstica para detectar alta reserva calórica, con puntos de corte óptimo para las puntuaciones Z-IMC menores a 2 Z scores. Esto resulta relevante para la identificación de exceso de adiposidad en poblaciones, en relación con la implementación de políticas públicas de prevención de enfermedades crónicas no transmisibles(AU)

The body mass index (BMI) is an effective tool to detect weight overload in children and adolescents, associated with body adiposity. Objective. To analyze the concordance, sensitivity and specificity of three international BMI/age references (WHO, IOTF and CDC) to diagnose excess weight and to know their diagnostic accuracy to identify excess adiposity in relation to the brachial fat area (BFA) in Argentine child-youth population. Materials and methods. A multicenter, descriptive- comparative and cross-sectional study was carried out between 2003 and 2008 in 22.658 Argentine children and adolescents between aged 4 to 13 years. From the weight, height, arm circumference and tricipital fold, BMI and BFA were calculated. The concordance, sensitivity, and specificity of BMI / age references (WHO, IOTF, CDC,) were analyzed and the diagnostic precision (ROC curves) to identify excess adiposity, from the BFA, as well as the optimal cut-off point (OCP). Results. The three references had good agreement, the highest sensitivity corresponded to WHO and the highest specificity to IOTF. The area under the curve (AUC) was greater in Z-BMI/IOTF in men and in Z-BMI/WHO in women. The OCPs showed discrepancies, being higher with WHO. Conclusion. The three references show similar diagnostic accuracy to detect high caloric reserve, but with cut-off points for Z-BMI scores less than 2 Z scores. This is relevant for the identification of excess adiposity in populations in relation to the implementation of public policies for the prevention of chronic non-communicable diseases(AU)

Comparative study of mid-upper arm circumference, arm muscle area and arm fat area percentiles in Argentinean and US children aged 4-14 years.

INTRODUCTION: Background: mid-upper arm circumference (MUAC), subcutaneous fat and muscle measurements are an alternative method to diagnose overweight and evaluate growth as well as protein and energy reserves. Aim: to compare MUAC, arm muscle area (AMA) and arm fat area (AFA) measurements of Argentinean boys and girls (Sa) with reference curves for US boys and girls (R). Subjects and methods: data from 22,736 school-children aged 4-14 years from six Argentinean provinces were collected. MUAC and triceps skinfold thickness were measured and the derived AMA and AFA measures were calculated. Analyses were performed with GAMLSS using the R software. Differences in mean values of Sa and R were compared in percentiles 3, 50 and 97. Results: mean values of MUAC and AMA in boys and girls were higher in R than in Sa at all ages; conversely, AFA values were lower. Conclusions: our results confirm differences in upper arm anthropometry of Argentinean school-children with respect to the US reference. The higher adipose tissue and lower skeletal muscle mass observed in Argentinean children could be partly associated with the different ethnic origin of both populations. However, differences should be interpreted in the context of an obesogenic environment, which has favored a calorie-protein imbalance.

INTRODUCCIÓN: Antecedentes: la medición de la circunferencia del brazo (MUAC), así como la estimación de la grasa subcutánea y muscular constituyen un método alternativo para diagnosticar el sobrepeso y evaluar el crecimiento y las reservas proteicas y energéticas. Objetivo: comparar las mediciones de MUAC, área muscular (AMA) y área grasa (AFA) del brazo de niños y niñas argentinos (Sa) con curvas de referencia para niños y niñas de Estados Unidos (R). Sujetos y métodos: se recopilaron datos de 22,736 escolares de 4 a 14 años de edad de seis provincias argentinas. Se obtuvieron medidas de MUAC y pliegue subcutáneo tricipital y se calcularon AMA y AFA. Los análisis se realizaron con GAMLSS utilizando el software R. Las diferencias en los valores medios de Sa y R se compararon para los percentiles 3, 50 y 97. Resultados: a todas las edades los valores medios de MUAC y AMA en niños y niñas fueron más altos en R que en Sa; por el contrario, los valores de AFA fueron más bajos. Conclusiones: nuestros resultados confirman la existencia de diferencias en la antropometría mesobraquial de los niños argentinos con respecto a los de la referencia. La mayor cantidad de tejido adiposo y menor de tejido muscular observada en los niños argentinos de ambos sexos puede ser parcialmente asociada con el diferente origen étnico de ambas poblaciones. Sin embargo, las diferencias podrían interpretarse en el contexto de un ambiente obesogénico, el cual habría favorecido el desbalance proteico-calórico.

Geographical altitude, size, mass and body surface area in children (1-4 years) in the Province of Jujuy (Argentina).

BACKGROUND: Highland child populations show low growth rates. AIM: To evaluate the variation of size, mass and body surface area of Jujenean infants (1-4 years) as a function of geographic altitude. SUBJECTS AND METHODS: Nutritional status of 8059 healthy infants was determined based on weight and height data; body mass index, ponderal index, body surface area, body surface area/mass and ectomorphy were calculated. Variables were standardized with a provincial mean and WHO references. Data were grouped by age, sex and geographic altitude: Highlands (≥2500 masl) and Lowlands (<2500 masl). Chi-square, correlation and t-tests were applied. RESULTS: Highlands infants had higher prevalence of stunting, reduced height, weight, body surface area and ectomorphy; also higher body mass index, ponderal index and body surface area/mass. The population average z-score for height, weight and body surface area was positive in Lowlands and negative in Highlands. The opposite happened with body mass index, ponderal index and body surface area/mass. In Highlands and Lowlands the average z-score reference was negative for weight and height and positive for body mass index. Correlations between indices were high and significant, higher in Highlands. CONCLUSION: Jujenean children differ in size, mass and body surface area based on the geographical altitude and adverse nutritional and socioeconomic factors.

Índice compuesto de fracaso antropométrico y altura geográfica en infantes jujeños (1-5 años) / Composite index of anthropometric failure and geographic altitude in children from Jujuy (1 to 5 years old)

Introducción. El índice compuesto de fracaso antropométrico (ICFA), integrado por los índices antropométricos habituales y sus combinaciones en 7 categorías, propone una medida agregada para ponderar la desnutrición como alternativa a la evaluación independiente del acortamiento, emaciación y bajo peso. Objetivo. Evaluar el ICFA en la población infantil jujeña asentada a distintos niveles altitudinales. Materiales y métodos. El peso y la talla se tomaron de los controles de niños sanos, de 1-5 años, realizados en los Centros de Atención Primaria (CAP) jujeños entre 2005 y 2007. El estado nutricional (bajo peso, acortamiento y emaciado) se caracterizó con el estándar OMS-2007. El ICFA y sus 7 grupos se calcularon agrupando los datos por sexo, edad y nivel altitudinal (tierras altas: > 2500 msnm; tierras bajas: < 2500msnm). Las diferencias porcentuales del ICFA por altura y sexo y edad se verificaron con la prueba chi-cuadrado. Resultados. Se incluyeron 8059 niños. El ICFA de tierras altas (6,1%) duplicó al de tierras bajas (3,4%) (p < 0,05) y la prevalencia de bajo peso (grupo Y) fue significativamente superior en tierras altas (p < 0,05). El ICFA y el acortamiento (grupo F) aumentaron con la edad, pero el aumento fue significativamente mayor en tierras altas. Conclusiones. Las tierras altas presentaron un IFCA significativamente mayor a expensas del acortamiento. No obstante, el índice de fracaso antropométrico no superó el 10% en los dos niveles, lo que da cuenta de un estado sanitario por desnutrición de escasa magnitud en la población infantil jujeña estudiada.

Introduction. The Composite Index of Anthropometric Failure (CIAF) is made up of typical anthropometric indicators and their combination into seven categories, and proposes an additional measure to study malnutrition as an alternative to the evaluation of stunting, wasting and underweight as separate measures. Objective. To assess the CIAF in the child population settled at different altitudinal zones in Jujuy. Population and Methods. Weight and height were obtained from healthy 1 to 5 year-old control children, measured at primary healthcare centers (PHCCs) in Jujuy between 2005 and 2007. Nutritional status indicators such as underweight, stunting and wasting were determined as per the World Health Organization 2007 child growth standards. The CIAF and its seven categories were estimated by grouping data by gender, age and altitudinal zone (highlands: >2500 MASL; lowlands: <2500 MASL). The CIAF percentage differences for height, gender and age were verified using a chi-square test. Results. A total of 8059 children were included. The CIAF for highland children (6.1%) doubled that for lowland children (3.4%) (p < 0.05), and underweight prevalence (group Y) was significantly higher in the highlands (p < 0.05). The CIAF value and stunting (group F) increased with age, but such increase was more significant in the highlands. Conclusions. A significantly higher CIAF was observed in highland children, at the expense of stunting. However, the index of anthropometric failure was not more than 10% at both the highlands and the lowlands, and this accounts for a scarcely significant malnutrition health status in the studied child population of Jujuy.

Indice compuesto de fracaso antropométrico y altura geográfica en infantes jujeños (1-5 años) / Composite index of anthropometric failure and geographic altitude in children from Jujuy (1 to 5 years old)

Introducción. El índice compuesto de fracaso antropométrico (ICFA), integrado por los índices antropométricos habituales y sus combinaciones en 7 categorías, propone una medida agregada para ponderar la desnutrición como alternativa a la evaluación independiente del acortamiento, emaciación y bajo peso. Objetivo. Evaluar el ICFA en la población infantil jujeña asentada a distintos niveles altitudinales. Materiales y métodos. El peso y la talla se tomaron de los controles de niños sanos, de 1-5 años, realizados en los Centros de Atención Primaria (CAP) jujeños entre 2005 y 2007. El estado nutricional (bajo peso, acortamiento y emaciado) se caracterizó con el estándar OMS-2007. El ICFA y sus 7 grupos se calcularon agrupando los datos por sexo, edad y nivel altitudinal (tierras altas: > 2500 msnm; tierras bajas: < 2500msnm). Las diferencias porcentuales del ICFA por altura y sexo y edad se verificaron con la prueba chi-cuadrado. Resultados. Se incluyeron 8059 niños. El ICFA de tierras altas (6,1%) duplicó al de tierras bajas (3,4%) (p < 0,05) y la prevalencia de bajo peso (grupo Y) fue significativamente superior en tierras altas (p < 0,05). El ICFA y el acortamiento (grupo F) aumentaron con la edad, pero el aumento fue significativamente mayor en tierras altas. Conclusiones. Las tierras altas presentaron un IFCA significativamente mayor a expensas del acortamiento. No obstante, el índice de fracaso antropométrico no superó el 10% en los dos niveles, lo que da cuenta de un estado sanitario por desnutrición de escasa magnitud en la población infantil jujeña estudiada.(AU)

Introduction. The Composite Index of Anthropometric Failure (CIAF) is made up of typical anthropometric indicators and their combination into seven categories, and proposes an additional measure to study malnutrition as an alternative to the evaluation of stunting, wasting and underweight as separate measures. Objective. To assess the CIAF in the child population settled at different altitudinal zones in Jujuy. Population and Methods. Weight and height were obtained from healthy 1 to 5 year-old control children, measured at primary healthcare centers (PHCCs) in Jujuy between 2005 and 2007. Nutritional status indicators such as underweight, stunting and wasting were determined as per the World Health Organization 2007 child growth standards. The CIAF and its seven categories were estimated by grouping data by gender, age and altitudinal zone (highlands: >2500 MASL; lowlands: <2500 MASL). The CIAF percentage differences for height, gender and age were verified using a chi-square test. Results. A total of 8059 children were included. The CIAF for highland children (6.1%) doubled that for lowland children (3.4%) (p < 0.05), and underweight prevalence (group Y) was significantly higher in the highlands (p < 0.05). The CIAF value and stunting (group F) increased with age, but such increase was more significant in the highlands. Conclusions. A significantly higher CIAF was observed in highland children, at the expense of stunting. However, the index of anthropometric failure was not more than 10% at both the highlands and the lowlands, and this accounts for a scarcely significant malnutrition health status in the studied child population of Jujuy.(AU)

Composite index of anthropometric failure and geographic altitude in children from Jujuy (1 to 5 years old).

INTRODUCTION: The Composite Index of Anthropometric Failure (CIAF) is made up of typical anthropometric indicators and their combination into seven categories, and proposes an additional measure to study malnutrition as an alternative to the evaluation of stunting, wasting and underweight as separate measures. OBJECTIVE: To assess the CIAF in the child population settled at different altitudinal zones in Jujuy. POPULATION AND METHODS: Weight and height were obtained from healthy 1 to 5 year-old control children, measured at primary healthcare centers (PHCCs) in Jujuy between 2005 and 2007. Nutritional status indicators such as underweight, stunting and wasting were determined as per the World Health Organization 2007 child growth standards. The CIAF and its seven categories were estimated by grouping data by gender, age and altitudinal zone (highlands: >2500 MASL; lowlands: <2500 MASL). The CIAF percentage differences for height, gender and age were verified using a chi-square test. RESULTS: A total of 8059 children were included. The CIAF for highland children (6.1%) doubled that for lowland children (3.4%) (p < 0.05), and underweight prevalence (group Y) was significantly higher in the highlands (p < 0.05). The CIAF value and stunting (group F) increased with age, but such increase was more significant in the highlands. CONCLUSIONS: A significantly higher CIAF was observed in highland children, at the expense of stunting. However, the index of anthropometric failure was not more than 10% at both the highlands and the lowlands, and this accounts for a scarcely significant malnutrition health status in the studied child population of Jujuy.

Composite index of anthropometric failure and geographic altitude in children from Jujuy (1 to 5 years old). / Composite index of anthropometric failure and geographic altitude in children from Jujuy (1 to 5 years old).

INTRODUCTION: The Composite Index of Anthropometric Failure (CIAF) is made up of typical anthropometric indicators and their combination into seven categories, and proposes an additional measure to study malnutrition as an alternative to the evaluation of stunting, wasting and underweight as separate measures. OBJECTIVE: To assess the CIAF in the child population settled at different altitudinal zones in Jujuy. POPULATION AND METHODS: Weight and height were obtained from healthy 1 to 5 year-old control children, measured at primary healthcare centers (PHCCs) in Jujuy between 2005 and 2007. Nutritional status indicators such as underweight, stunting and wasting were determined as per the World Health Organization 2007 child growth standards. The CIAF and its seven categories were estimated by grouping data by gender, age and altitudinal zone (highlands: >2500 MASL; lowlands: <2500 MASL). The CIAF percentage differences for height, gender and age were verified using a chi-square test. RESULTS: A total of 8059 children were included. The CIAF for highland children (6.1

) doubled that for lowland children (3.4

) (p < 0.05), and underweight prevalence (group Y) was significantly higher in the highlands (p < 0.05). The CIAF value and stunting (group F) increased with age, but such increase was more significant in the highlands. CONCLUSIONS: A significantly higher CIAF was observed in highland children, at the expense of stunting. However, the index of anthropometric failure was not more than 10

at both the highlands and the lowlands, and this accounts for a scarcely significant malnutrition health status in the studied child population of Jujuy.

Prevalencia de sobrepeso y obesidad en escolares jujeños de diferente nivel altitudinal según las referencias IOTF, CDC y OMS / Prevalence of overweight and obesity in students from different altitudinal zones of Jujuy according to three intvernational references (IOTF, CDC and WHO)

Introducción. Se comparan las prevalencias de sobrepeso (SP) y obesidad (OB) en escolares jujeños de distintos niveles altitudinales utilizando las referencias de la International Obesity Task Force (IOTF), de los Centers for Disease Control (CDC) y de la Organización Mundial de la Salud (OMS), y la concordancia entre ellas. Materiales y métodos. Los datos de peso y talla de 15 541 escolares (PROSANE) se agruparon en tierras altas (TA) (= 2500 msnm) y bajas (TB) (< 2500 msnm), y en dos grupos de edad (5 a 6,99 y 11 a 12,99 años). Se calcularon las prevalencias de SP, OB y SP+OB según las referencias. Las diferencias entre variables y prevalencias se establecieron con la prueba de la ?² y la prueba de la t, y la concordancia entre criterios, con el índice kappa. Resultados. Los escolares de las TA presentaron menor peso, talla e índice de masa corporal (IMC) (p< 0,05). Las prevalencias de SP, OB y SP+OB con OMS fueron superiores, excepto para SP en ambos sexos de 11 a 12,99 años de TB y TA. Independientemente de las referencias, el sexo y la edad, las prevalencias de SP, OB y SP+OB fueron, en general, mayores en las TB. La concordancia entre las referencias IOTF/CDC fue buena-muy buena, y entre estas y las de la OMS, regular-moderada. Conclusiones. Los escolares de TA presentaron menor prevalencia de SB y OB. La mejor concordancia se dio entre las referencias IOTF y CDC.

Introduction. Prevalences of overweight and obesity in students from different altitudinal zones of Jujuy are compared using the International Obesity Task Force (IOTF), the Centers for Disease Control (CDC) and the World Health Organization (WHO) references, and the agreement among them. Material and Methods. Weight and height data from 15 541 students were grouped in highlands (HL) (=2500 MASL) and lowlands (LL) (<2500 MASL) and in two age groups (5-6.99 years old and 11-12.99 years old). Overweight and obesity prevalences were calculated according to the different references. The differences in outcome measures and prevalences were established using the ?2 test and the t test, and agreement among the criteria was calculated using the kappa index. Results. Students from the HL had lower weight, height and body mass index (BMI) values (p< 0.05). Overweight and obesity prevalences compared to the WHO reference were higher, except for overweight in students of both sexes, from 11 to 12.99 years old, from the HL and the LL. Regardless of the references, gender and age, overweight and obesity prevalences were generally higher in the LL. Agreement between the IOTF and the CDC was good-very good, and agreement among them and the WHO was fair-moderate. Conclusions. Students from the HL had a lower overweight and obesity prevalence. The greatest agreement was observed between the IOTF and the CDC references.

Prevalencia de sobrepeso y obesidad en escolares jujeños de diferente nivel altitudinal según las referencias IOTF, CDC y OMS / Prevalence of overweight and obesity in students from different altitudinal zones of Jujuy according to three intvernational references (IOTF, CDC and WHO)

Introducción. Se comparan las prevalencias de sobrepeso (SP) y obesidad (OB) en escolares jujeños de distintos niveles altitudinales utilizando las referencias de la International Obesity Task Force (IOTF), de los Centers for Disease Control (CDC) y de la Organización Mundial de la Salud (OMS), y la concordancia entre ellas. Materiales y métodos. Los datos de peso y talla de 15 541 escolares (PROSANE) se agruparon en tierras altas (TA) (= 2500 msnm) y bajas (TB) (< 2500 msnm), y en dos grupos de edad (5 a 6,99 y 11 a 12,99 años). Se calcularon las prevalencias de SP, OB y SP+OB según las referencias. Las diferencias entre variables y prevalencias se establecieron con la prueba de la ?² y la prueba de la t, y la concordancia entre criterios, con el índice kappa. Resultados. Los escolares de las TA presentaron menor peso, talla e índice de masa corporal (IMC) (p< 0,05). Las prevalencias de SP, OB y SP+OB con OMS fueron superiores, excepto para SP en ambos sexos de 11 a 12,99 años de TB y TA. Independientemente de las referencias, el sexo y la edad, las prevalencias de SP, OB y SP+OB fueron, en general, mayores en las TB. La concordancia entre las referencias IOTF/CDC fue buena-muy buena, y entre estas y las de la OMS, regular-moderada. Conclusiones. Los escolares de TA presentaron menor prevalencia de SB y OB. La mejor concordancia se dio entre las referencias IOTF y CDC.(AU)

Introduction. Prevalences of overweight and obesity in students from different altitudinal zones of Jujuy are compared using the International Obesity Task Force (IOTF), the Centers for Disease Control (CDC) and the World Health Organization (WHO) references, and the agreement among them. Material and Methods. Weight and height data from 15 541 students were grouped in highlands (HL) (=2500 MASL) and lowlands (LL) (<2500 MASL) and in two age groups (5-6.99 years old and 11-12.99 years old). Overweight and obesity prevalences were calculated according to the different references. The differences in outcome measures and prevalences were established using the ?2 test and the t test, and agreement among the criteria was calculated using the kappa index. Results. Students from the HL had lower weight, height and body mass index (BMI) values (p< 0.05). Overweight and obesity prevalences compared to the WHO reference were higher, except for overweight in students of both sexes, from 11 to 12.99 years old, from the HL and the LL. Regardless of the references, gender and age, overweight and obesity prevalences were generally higher in the LL. Agreement between the IOTF and the CDC was good-very good, and agreement among them and the WHO was fair-moderate. Conclusions. Students from the HL had a lower overweight and obesity prevalence. The greatest agreement was observed between the IOTF and the CDC references.(AU)

Prevalence of overweight and obesity in students from different altitudinal zones of Jujuy according to three international references (IOTF, CDC and WHO).

INTRODUCTION. Prevalences of overweight and obesity in students from different altitudinal zones of Jujuy are compared using the International Obesity Task Force (IOTF), the Centers for Disease Control (CDC) and the World Health Organization (WHO) references, and the agreement among them. MATERIAL AND METHODS. Weight and height data from 15 541 students were grouped in highlands (HL) (≥2500 MASL) and lowlands (LL) (<2500 MASL) and in two age groups (5-6.99 years old and 11-12.99 years old). Overweight and obesity prevalences were calculated according to the different references. The differences in outcome measures and prevalences were established using the ?2 test and the t test, and agreement among the criteria was calculated using the kappa index. RESULTS. Students from the HL had lower weight, height and body mass index (BMI) values (p< 0.05). Overweight and obesity prevalences compared to the WHO reference were higher, except for overweight in students of both sexes, from 11 to 12.99 years old, from the HL and the LL. Regardless of the references, gender and age, overweight and obesity prevalences were generally higher in the LL. Agreement between the IOTF and the CDC was good-very good, and agreement among them and the WHO was fair-moderate. CONCLUSIONS. Students from the HL had a lower overweight and obesity prevalence. The greatest agreement was observed between the IOTF and the CDC references.

Prevalence of overweight and obesity in students from different altitudinal zones of Jujuy according to three international references (IOTF, CDC and WHO). / Prevalence of overweight and obesity in students from different altitudinal zones of Jujuy according to three international references (IOTF, CDC and WHO).

INTRODUCTION. Prevalences of overweight and obesity in students from different altitudinal zones of Jujuy are compared using the International Obesity Task Force (IOTF), the Centers for Disease Control (CDC) and the World Health Organization (WHO) references, and the agreement among them. MATERIAL AND METHODS. Weight and height data from 15 541 students were grouped in highlands (HL) (2500 MASL) and lowlands (LL) (<2500 MASL) and in two age groups (5-6.99 years old and 11-12.99 years old). Overweight and obesity prevalences were calculated according to the different references. The differences in outcome measures and prevalences were established using the ?2 test and the t test, and agreement among the criteria was calculated using the kappa index. RESULTS. Students from the HL had lower weight, height and body mass index (BMI) values (p< 0.05). Overweight and obesity prevalences compared to the WHO reference were higher, except for overweight in students of both sexes, from 11 to 12.99 years old, from the HL and the LL. Regardless of the references, gender and age, overweight and obesity prevalences were generally higher in the LL. Agreement between the IOTF and the CDC was good-very good, and agreement among them and the WHO was fair-moderate. CONCLUSIONS. Students from the HL had a lower overweight and obesity prevalence. The greatest agreement was observed between the IOTF and the CDC references.