Estudio observacional, transversal y analítico realizado con 2201 niños y adolescentes, estudiantes de primaria, secundaria y preparatoria de México con el objetivo de analizar la relación entre sus percepciones de violencia del país y su municipio, inseguridad en su colonia y escuela y su rol en bullying escolar: observador, víctima o acosador. En México existen dos preocupantes fenómenos: la violencia vinculada al narcotráfico y los eventos de bullying escolar y en este trabajo se buscó aportar a explicar sus posibles relaciones. Se usó un cuestionario autoaplicado en línea y análisis estadístico con Ji cuadrado y regresión logística encontrando algunas asociaciones significativas entre la violencia, inseguridad percibida y los roles en bullying. Las variables contextuales como la violencia deben considerarse en programas de prevención y atención del bullying.

An observational, cross-sectional and analytic study was carried out with 2201 students of elementary, middle and high schools in Mexico. The aim of this study was to analyze the relationship between their perceptions of country, and county violence, neighborhood and school insecurity and its role in bullying as witness, victim and bully. Two disturbing phenomena in Mexico Drugs are trafficking and scholar bullying. We wish to contribute to explanain of their possible relationships. An on line self-report questionnaire was used; Chi-square analysis and logistic Regression were done. We found some significant associations between violence, perceived insecurity and its role in bullying. The contextual variables such as violence should be considered in bullying prevention and care programs.

Estudo observacional, transversal e analítico com 2201 crianças e adolescentes, alunos da primária, secundária e ensino medio do México, com o objetivo de analisar a relação entre as percepções da violência no país e o seu município, insegurança no seu bairro, escola e seu papel nos eventos de bullying escolar: observador, vítima ou perseguidor. No México há dois fenómenos preocupantes: violência ligada ao tráfico de drogas e os eventos de bullying escolar e neste trabalho procura-se contribuir para a explicação de sues possíveis relaçãos. Utilizou-se um questionário auto-aplicado em linha fazendo análise estatística com o Chi-quadrado e regressão logística encontrando algumas associações significativas entre a violência, a insegurança percebida e os papéis em bullying. As variáveis contextuais, tais como a violência devem ser consideradas em programas de prevenção e atenção do bullying.

With the aim of evaluating the association between physical activity and sedentary behavior with quality of life (QoL) in undergraduate students of Ciudad Guzman, state of Jalisco, Mexico, a total of 881 adolescents aged between 17 and 19 were studied. Online questionnaires were used, namely the research version of the Youth Quality of Life Instrument and the Youth Risk Behavior Survey. Odd ratios (OR) were obtained using simple and multivariate logistic regression analysis. The number of days with physical activity was related to a higher total perceptual score, higher general QoL domain, higher self domain as well as higher environment domain. Playing in > 2 sports teams was related to a higher total perceptual score, higher general QoL domain, higher self domain as well as higher environment domain. Having 4-5 physical education classes/week was related with a higher general QoL domain. Limiting recreational screen time to < 2 hours/day was related with a higher relationship domain. In conclusion, in Mexican undergraduate adolescent students, higher QoL was associated with: physical activity at least 4 days/week; physical education classes 4 or more days/week; playing in 2 or more sports teams and limiting recreational screen time to 2 hours or less.

Con el objeto de evaluar la asociación de la actividad física y conductas sedentarias con la calidad de vida en universitarios en Ciudad Guzmán, Jalisco, México, se estudiaron 881 adolescentes de 17-19 años de edad. Se utilizaron los cuestionarios en línea: Youth Quality of Life Instrument Research versión y el Youth Risk Behavior Survey. Se obtuvo razón de momios [RM] mediante regresión logística simple y múltiple. El número de días de actividad física se relacionó con el índice total superior, dominios general superior, personal superior y ambiental superior. Jugar en > 2 equipos deportivos se relacionó con el índice total superior, dominio general superior, dominio personal superior y dominio ambiental superior. Tener 4-5 clases de educación física a la semana se relacionó con el dominio general superior. Pasar dos o menos horas al día frente a la pantalla se relacionó con el dominio relacional superior. En conclusión, en los universitarios adolescentes mexicanos se asoció a indicadores de mejor calidad de vida, el realizar actividad física 4 o más días a la semana, asistir a clases de educación física 4 o 5 semanales, participar en 2 o más equipos deportivos y pasar menos de 2 horas diarias horas frente a pantallas en actividades recreativas.

With the aim of evaluating the association between physical activity and sedentary behavior with quality of life (QoL) in undergraduate students of Ciudad Guzman, state of Jalisco, Mexico, a total of 881 adolescents aged between 17 and 19 were studied. Online questionnaires were used, namely the research version of the Youth Quality of Life Instrument and the Youth Risk Behavior Survey. Odd ratios (OR) were obtained using simple and multivariate logistic regression analysis. The number of days with physical activity was related to a higher total perceptual score, higher general QoL domain, higher self domain as well as higher environment domain. Playing in > 2 sports teams was related to a higher total perceptual score, higher general QoL domain, higher self domain as well as higher environment domain. Having 4-5 physical education classes/week was related with a higher general QoL domain. Limiting recreational screen time to < 2 hours/day was related with a higher relationship domain. In conclusion, in Mexican undergraduate adolescent students, higher QoL was associated with: physical activity at least 4 days/week; physical education classes 4 or more days/week; playing in 2 or more sports teams and limiting recreational screen time to 2 hours or less.

Con el objeto de evaluar la asociación de la actividad física y conductas sedentarias con la calidad de vida en universitarios en Ciudad Guzmán, Jalisco, México, se estudiaron 881 adolescentes de 17-19 años de edad. Se utilizaron los cuestionarios en línea: Youth Quality of Life Instrument Research versión y el Youth Risk Behavior Survey. Se obtuvo razón de momios [RM] mediante regresión logística simple y múltiple. El número de días de actividad física se relacionó con el índice total superior, dominios general superior, personal superior y ambiental superior. Jugar en > 2 equipos deportivos se relacionó con el índice total superior, dominio general superior, dominio personal superior y dominio ambiental superior. Tener 4-5 clases de educación física a la semana se relacionó con el dominio general superior. Pasar dos o menos horas al día frente a la pantalla se relacionó con el dominio relacional superior. En conclusión, en los universitarios adolescentes mexicanos se asoció a indicadores de mejor calidad de vida, el realizar actividad física 4 o más días a la semana, asistir a clases de educación física 4 o 5 semanales, participar en 2 o más equipos deportivos y pasar menos de 2 horas diarias horas frente a pantallas en actividades recreativas.

This cross-sectional study analyzed by gender the association between body weight perception and weight control behavior with quality of life (QL) in 563 middle school students (age x‾ = 13.3, SD = 0.94), from all grades of nine middle schools of South region of Jalisco state realized in 2010. There were 51.9% boys and 19.8% worked. A self-administered questionnaire on line was used (YQOL-R), perceptual module, and five items of body weight adapted from 2009 Middle School YRBS. Statistical analysis included chi squared, Student t test, Spearman correlation, ANOVA and Tamhane's T2. Results: QOL was higher in normal weight perception category than low weight or overweight perception categories; a negative correlation between QOL and weight perception was observed (overweight r s = -.22; low weight r s = -.16); QOL was lower in those who tried to maintain weight in total sample and in girls in relation to those who tried to maintained it. We concluded that weight control behavior is associated with weight perception and both are associated with quality of life. Gender was important to understand the variables studied.

Este estudio transversal analizó la asociación de la percepción del peso corporal y el comportamiento alimentario de control de peso con la calidad de vida (CV) por género, en 563 estudiantes de secundaria (edad x‾ = 13.3, DE = 0.94) de todos los grados de nueve secundarias de la región del sur de Jalisco realizado en 2010. Eran 51.9% varones, 19.8% del total trabajaban. Se auto-administró en línea un cuestionario de CV (YQOL-R) módulo perceptual, y cinco ítems acerca del peso adaptados del 2009 Middle School YRBS. Estadística: chi cuadrada, t de Student, p de Spearman y ANOVA, T2 de Tamhane. Resultados: CV más alta para peso percibido cercano al correcto, respecto a bajo peso y sobrepeso; correlación negativa entre CV y percepción del peso (sobrepeso r s = -.22; bajo peso r s = -.16); CV más baja en quienes trataban de mantenerse en su peso en muestra total y en mujeres respecto a las que querían mantenerlo. Concluimos que el comportamiento alimentario está asociado de manera importante a la percepción del peso y ambos a la calidad de vida, y el género es fundamental para comprender las variables estudiadas.

The aim of this study was to analyze quality of life (QoL) according to self-perceived weight and weight control behaviors, by gender. The sample consisted of 2,401 adolescent students (17-19 years of age) enrolled from 2007 to 2009 at a Mexican university; 61.9% were women, 19.4% worked, and 99.2% were single. An online self-administered questionnaire was used that included the perceptual module of the YQOL-R and seven items on body weight, adapted from YRBS 2007. RESULTS: 52% of women and 31.7% of men were attempting to lose weight. The highest QoL scores were in students who felt they were near the right weight, those who were attempting to maintain the same weight, and those who exercised. Lowest QoL was reported by those who considered themselves overweight, were trying to lose weight, were eating less, were skipping meals, or were using unsupervised dieting, vomiting, or laxatives. In women, QoL differed between those maintaining the same weight, gaining weight, and losing weight, while QoL in men only differed for those attempting to gain weight. The findings could be useful in educational processes, preventive programs, and assessment of interventions.

El objetivo de este estudio fue analizar la calidad de vida (CV), según auto percepción del peso corporal y comportamientos de control de peso, por género, en 2.401 estudiantes de 17 a 19 años de primer ingreso en un centro universitario en México del 2007 al 2009; 61,9% mujeres, 80,6% no trabajaban y 99,2% solteros. Se auto administró en línea un cuestionario genérico de CV (YQOL-R) módulo perceptual, y siete ítems acerca del peso adaptados del YRBS 2007. Se observó que un 52% de mujeres y un 31,7% de hombres trataba de bajar de peso. CV más alta para peso cercano al correcto, quienes trataban de mantenerse en su peso y los que hacían ejercicio; CV más baja para quienes reportaron mucho sobrepeso, mujeres que trataban de bajar de peso, comían menos, dejaban de comer, hacían dieta sin supervisión, vomitaban o tomaban laxantes. En mujeres la CV fue diferente si trataban de mantenerse, subir o bajar de peso; en hombres sólo al tratar de subir. Esta información puede ser de utilidad para procesos educativos, programas de prevención y para evaluar las intervenciones.

The aim of this study was to analyze quality of life (QoL) according to self-perceived weight and weight control behaviors, by gender. The sample consisted of 2,401 adolescent students (17-19 years of age) enrolled from 2007 to 2009 at a Mexican university; 61.9% were women, 19.4% worked, and 99.2% were single. An online self-administered questionnaire was used that included the perceptual module of the YQOL-R and seven items on body weight, adapted from YRBS 2007. RESULTS: 52% of women and 31.7% of men were attempting to lose weight. The highest QoL scores were in students who felt they were near the right weight, those who were attempting to maintain the same weight, and those who exercised. Lowest QoL was reported by those who considered themselves overweight, were trying to lose weight, were eating less, were skipping meals, or were using unsupervised dieting, vomiting, or laxatives. In women, QoL differed between those maintaining the same weight, gaining weight, and losing weight, while QoL in men only differed for those attempting to gain weight. The findings could be useful in educational processes, preventive programs, and assessment of interventions.

El objetivo de este estudio fue analizar la calidad de vida (CV), según auto percepción del peso corporal y comportamientos de control de peso, por género, en 2.401 estudiantes de 17 a 19 años de primer ingreso en un centro universitario en México del 2007 al 2009; 61,9% mujeres, 80,6% no trabajaban y 99,2% solteros. Se auto administró en línea un cuestionario genérico de CV (YQOL-R) módulo perceptual, y siete ítems acerca del peso adaptados del YRBS 2007. Se observó que un 52% de mujeres y un 31,7% de hombres trataba de bajar de peso. CV más alta para peso cercano al correcto, quienes trataban de mantenerse en su peso y los que hacían ejercicio; CV más baja para quienes reportaron mucho sobrepeso, mujeres que trataban de bajar de peso, comían menos, dejaban de comer, hacían dieta sin supervisión, vomitaban o tomaban laxantes. En mujeres la CV fue diferente si trataban de mantenerse, subir o bajar de peso; en hombres sólo al tratar de subir. Esta información puede ser de utilidad para procesos educativos, programas de prevención y para evaluar las intervenciones.

OBJECTIVE: To evaluate the association between objective and subjective knowledge on HIV/AIDS and condom use. MATERIAL AND METHODS: Analysis of a database from an anonymous, self-applied, randomized survey conducted between 1995 and 1996. Study subjects were 1 410 adolescents of four socioeconomic strata from Guadalajara, Mexico. Objective knowledge was assessed with 24 questions regarding HIV/AIDS, and subjective knowledge with the question "how much do you think you know about HIV/AIDS?" The variables associated with condom use were identified using logistic regression analysis and by calculating odds ratios with a 95% confidence interval. RESULTS: The degree of objective knowledge was "average", differentiated by socioeconomic strata (p< 0.001), and was higher in adolescents from medium and high socioeconomic strata (p< 0.008). Regarding subjective knowledge, adolescents from the low, medium, and high socioeconomic strata claimed to know "a little", and the ones from the lowest stratum claimed to know "very little". Condom use was higher in males (35.4%), and in adolescents from high socioeconomic strata (p< 0.005), than in females (15.3%) (p< 0.001). Although there was a correlation between objective and subjective knowledge (r = 0.37, p< 0.001), a higher degree of subjective knowledge was associated with condom use (p< 0.001). CONCLUSIONS: Subjective knowledge, belonging to medium and high socioeconomic strata and being male, were predictors of condom use.

OBJETIVO: Evaluar la asociación de conocimientos objetivo y subjetivo sobre VIH/SIDA con el uso del condón. MATERIAL Y MÉTODOS: Se analizó la base de datos de una encuesta aleatoria, anónima y autoaplicada en 1 410 adolescentes de cuatro estratos socioeconómicos de Guadalajara, Jalisco, México, entre 1995 y 1996. El conocimiento objetivo se evaluó mediante 24 preguntas sobre VIH/SIDA y el "subjetivo" con la pregunta: "¿qué tanto crees conocer sobre el SIDA?" Las variables predictoras del uso del condón se identificaron mediante regresión logística y cálculo de la razón de momios con IC 95%. RESULTADOS: El nivel de conocimiento objetivo fue regular y tuvo diferencias por estratos (p< 0.001) favoreciendo al medio y superior (p= 0.008). Del conocimiento subjetivo, los de estratos alto, medio y bajo percibieron saber "algo", y los del marginado "poco". Los varones dijeron usar más el condón (35.4%) que las mujeres (15.3%) (p< 0.001), y los de estratos superiores (p< 0.005). Aunque conocimiento objetivo y subjetivo se correlacionaron (r= 0.37, p< 0.001), un mayor conocimiento subjetivo se asoció con el uso del condón (p< 0.001). CONCLUSIONES: Conocimiento subjetivo, pertenecer al estrato alto o medio y ser varón, predijeron el uso constante del condón. Su uso fue diferencial por género y estrato socioeconómico.

OBJECTIVE: To assess STI/AIDS risk behaviors and occupational risk factors among adolescent hotel workers in Puerto Vallarta. MATERIAL AND METHODS: Comparative cross-sectional study conducted in 1998, among 288 workers adolescents of 38 hotels in Puerto Vallarta, Mexico. Variables were collected on working conditions, environmental conditions, STI/AIDS risk behaviors, and sociodemographic characteristics. Statistical analysis consisted of descriptive and multivariate techniques: t test, OR, and logistic regression. RESULTS: Study subjects had a mean age of 17.7 years; 71.5% were males. Fifty-three percent had active sexual relations; 93.6% of them had one or more STI/AIDS risk behaviors. Inadequate condom use was found in 77.3%, and 41% drank alcoholic beverages before intercourse. Promiscuity was reported by 29.9%, and anal relations by 9.2%. Associated factors were: perception of a sexually-arousing environment (OR 2.36), alcohol drinking by peers (OR 2.52) and guests (OR 2.60) before sexual intercourse, hotel rules allowing tourist guests in hotel rooms (OR 4.46). Confouding variables were: male gender (OR 3.14), being married or in common law (OR 21.19), and being 18-19 years of age (OR 3.11). CONCLUSIONS: The high frequency of STI/AIDS risk behaviors among adolescent hotel workers is associated to specific environmental factors.

OBJETIVO: Explorar comportamientos de riesgo de ITS/ SIDA de adolescentes trabajadores de hoteles de Puerto Vallarta, México, y su asociación con el ambiente laboral. MATERIAL Y MÉTODOS: Estudio transversal, comparativo, en una población de 288 adolescentes trabajadores durante 1998 en 38 hoteles de Puerto Vallarta. Variables: condición laboral, situación ambiental, comportamiento de riesgo de ITS/SIDA, características sociodemográficas. Estadísticas descriptivas, asociativas y predictivas: t test, RM y regresión logística. RESULTADOS: Edad promedio 17.7 años; 71.5% hombres; activos sexualmente 53%; con uno o más comportamientos de riesgo de ITS/SIDA, (93.6%): nunca o raramente usa condón (77.3.1%); beber antes de relaciones sexuales (41%); promiscuidad (29.9%), y relaciones anales (9.2%). Factores asociados: percibir el ambiente estimulante para relaciones sexuales (RM 2.36); beber antes de coito: compañeros (RM 2.52) y huéspedes (RM 2.60); norma de poder invitar huéspedes al cuarto (RM 4.46); Variables confusoras: género masculino (RM 3.14), casados o en unión libre (RM 21.19) y 18-19 años (RM 3.11). CONCLUSIONES: Hay alta frecuencia de comportamiento de riesgo de ITS/SIDA, asociados con algunos factores ambientales.

OBJECTIVE: To validate a self-administered questionnaire about social and corporal sexual behaviors among adolescents, by school level and gender. MATERIAL AND METHODS: The data collection instrument was constructed according to DeVellis and consisted of 26 items. It was used in a prospective longitudinal study conducted in 1994 in Guadalajara, Mexico, among 1243 secondary and high school students. The construct validity of the instrument was established using exploratory factorial analysis, and its reliability using the Cronbach's alpha test. RESULTS: Five factors were obtained in males and an equal number in women, using eigenvalues >1 and by forcing the best solution. The explained variance was 59.3-70.6%; the factorial weight average was 0.63-0.75, and 13 different factors were selected. The Cronbach's alpha mean was 0.87-0.93 and 16 factors had Cronbach's alpha over 0.70. CONCLUSIONS: The instrumen has an acceptable validity and reliability for studying the sexual, social, and corporal behaviors in adolescents similar populations.

OBJETIVO: Validar un cuestionario autoadministrado de comportamientos sexuales, sociales y corporales para adolescentes por nivel escolar y género. MATERIAL Y MÉTODOS: Instrumento de 26 preguntas construido según DeVellis, aplicado en un estudio longitudinal prospectivo, hecho en 1994 a 1 243 alumnos y alumnas de secundaria y preparatoria en Guadalajara, Jalisco, México. Validez de constructo establecida por análisis factorial exploratorio y la confiabilidad por la prueba Alfa de Cronbach. RESULTADOS: Aparecen cinco factores en hombres usando valores propios (eigenvalue) >1 y cinco en mujeres, forzando la mejor solución. Veinte factores explican entre 59.3 y 70.6% de varianza, con promedio de pesos factoriales de 0.63- 0.75, y con 13 factores diferentes. El promedio de Alfa de Cronbach fue de 0.87-0.93 y en 16 factores hubo valores de Alpha de 0.71 o más. CONCLUSIONES: Cuestionario para poblaciones equivalentes con validez de constructo y confiabilidad interna aceptables.

OBJECTIVE: To validate a self-administered questionnaire about social and corporal sexual behaviors among adolescents, by school level and gender. MATERIAL AND METHODS: The data collection instrument was constructed according to DeVellis and consisted of 26 items. It was used in a prospective longitudinal study conducted in 1994 in Guadalajara, Mexico, among 1243 secondary and high school students. The construct validity of the instrument was established using exploratory factorial analysis, and its reliability using the Cronbach's alpha test. RESULTS: Five factors were obtained in males and an equal number in women, using eigenvalues >1 and by forcing the best solution. The explained variance was 59.3-70.6%; the factorial weight average was 0.63-0.75, and 13 different factors were selected. The Cronbach's alpha mean was 0.87-0.93 and 16 factors had Cronbach's alpha over 0.70. CONCLUSIONS: The instrumen has an acceptable validity and reliability for studying the sexual, social, and corporal behaviors in adolescents similar populations.

OBJETIVO: Validar un cuestionario autoadministrado de comportamientos sexuales, sociales y corporales para adolescentes por nivel escolar y género. MATERIAL Y MÉTODOS: Instrumento de 26 preguntas construido según DeVellis, aplicado en un estudio longitudinal prospectivo, hecho en 1994 a 1 243 alumnos y alumnas de secundaria y preparatoria en Guadalajara, Jalisco, México. Validez de constructo establecida por análisis factorial exploratorio y la confiabilidad por la prueba Alfa de Cronbach. RESULTADOS: Aparecen cinco factores en hombres usando valores propios (eigenvalue) >1 y cinco en mujeres, forzando la mejor solución. Veinte factores explican entre 59.3 y 70.6% de varianza, con promedio de pesos factoriales de 0.63- 0.75, y con 13 factores diferentes. El promedio de Alfa de Cronbach fue de 0.87-0.93 y en 16 factores hubo valores de Alpha de 0.71 o más. CONCLUSIONES: Cuestionario para poblaciones equivalentes con validez de constructo y confiabilidad interna aceptables.

OBJECTIVE: To assess STI/AIDS risk behaviors and occupational risk factors among adolescent hotel workers in Puerto Vallarta. MATERIAL AND METHODS: Comparative cross-sectional study conducted in 1998, among 288 workers adolescents of 38 hotels in Puerto Vallarta, Mexico. Variables were collected on working conditions, environmental conditions, STI/AIDS risk behaviors, and sociodemographic characteristics. Statistical analysis consisted of descriptive and multivariate techniques: t test, OR, and logistic regression. RESULTS: Study subjects had a mean age of 17.7 years; 71.5% were males. Fifty-three percent had active sexual relations; 93.6% of them had one or more STI/AIDS risk behaviors. Inadequate condom use was found in 77.3%, and 41% drank alcoholic beverages before intercourse. Promiscuity was reported by 29.9%, and anal relations by 9.2%. Associated factors were: perception of a sexually-arousing environment (OR 2.36), alcohol drinking by peers (OR 2.52) and guests (OR 2.60) before sexual intercourse, hotel rules allowing tourist guests in hotel rooms (OR 4.46). Confouding variables were: male gender (OR 3.14), being married or in common law (OR 21.19), and being 18-19 years of age (OR 3.11). CONCLUSIONS: The high frequency of STI/AIDS risk behaviors among adolescent hotel workers is associated to specific environmental factors.

OBJETIVO: Explorar comportamientos de riesgo de ITS/ SIDA de adolescentes trabajadores de hoteles de Puerto Vallarta, México, y su asociación con el ambiente laboral. MATERIAL Y MÉTODOS: Estudio transversal, comparativo, en una población de 288 adolescentes trabajadores durante 1998 en 38 hoteles de Puerto Vallarta. Variables: condición laboral, situación ambiental, comportamiento de riesgo de ITS/SIDA, características sociodemográficas. Estadísticas descriptivas, asociativas y predictivas: t test, RM y regresión logística. RESULTADOS: Edad promedio 17.7 años; 71.5% hombres; activos sexualmente 53%; con uno o más comportamientos de riesgo de ITS/SIDA, (93.6%): nunca o raramente usa condón (77.3.1%); beber antes de relaciones sexuales (41%); promiscuidad (29.9%), y relaciones anales (9.2%). Factores asociados: percibir el ambiente estimulante para relaciones sexuales (RM 2.36); beber antes de coito: compañeros (RM 2.52) y huéspedes (RM 2.60); norma de poder invitar huéspedes al cuarto (RM 4.46); Variables confusoras: género masculino (RM 3.14), casados o en unión libre (RM 21.19) y 18-19 años (RM 3.11). CONCLUSIONES: Hay alta frecuencia de comportamiento de riesgo de ITS/SIDA, asociados con algunos factores ambientales.

OBJECTIVE: To evaluate the association between objective and subjective knowledge on HIV/AIDS and condom use. MATERIAL AND METHODS: Analysis of a database from an anonymous, self-applied, randomized survey conducted between 1995 and 1996. Study subjects were 1 410 adolescents of four socioeconomic strata from Guadalajara, Mexico. Objective knowledge was assessed with 24 questions regarding HIV/AIDS, and subjective knowledge with the question "how much do you think you know about HIV/AIDS?" The variables associated with condom use were identified using logistic regression analysis and by calculating odds ratios with a 95% confidence interval. RESULTS: The degree of objective knowledge was "average", differentiated by socioeconomic strata (p< 0.001), and was higher in adolescents from medium and high socioeconomic strata (p< 0.008). Regarding subjective knowledge, adolescents from the low, medium, and high socioeconomic strata claimed to know "a little", and the ones from the lowest stratum claimed to know "very little". Condom use was higher in males (35.4%), and in adolescents from high socioeconomic strata (p< 0.005), than in females (15.3%) (p< 0.001). Although there was a correlation between objective and subjective knowledge (r = 0.37, p< 0.001), a higher degree of subjective knowledge was associated with condom use (p< 0.001). CONCLUSIONS: Subjective knowledge, belonging to medium and high socioeconomic strata and being male, were predictors of condom use.

OBJETIVO: Evaluar la asociación de conocimientos objetivo y subjetivo sobre VIH/SIDA con el uso del condón. MATERIAL Y MÉTODOS: Se analizó la base de datos de una encuesta aleatoria, anónima y autoaplicada en 1 410 adolescentes de cuatro estratos socioeconómicos de Guadalajara, Jalisco, México, entre 1995 y 1996. El conocimiento objetivo se evaluó mediante 24 preguntas sobre VIH/SIDA y el "subjetivo" con la pregunta: "¿qué tanto crees conocer sobre el SIDA?" Las variables predictoras del uso del condón se identificaron mediante regresión logística y cálculo de la razón de momios con IC 95%. RESULTADOS: El nivel de conocimiento objetivo fue regular y tuvo diferencias por estratos (p< 0.001) favoreciendo al medio y superior (p= 0.008). Del conocimiento subjetivo, los de estratos alto, medio y bajo percibieron saber "algo", y los del marginado "poco". Los varones dijeron usar más el condón (35.4%) que las mujeres (15.3%) (p< 0.001), y los de estratos superiores (p< 0.005). Aunque conocimiento objetivo y subjetivo se correlacionaron (r= 0.37, p< 0.001), un mayor conocimiento subjetivo se asoció con el uso del condón (p< 0.001). CONCLUSIONES: Conocimiento subjetivo, pertenecer al estrato alto o medio y ser varón, predijeron el uso constante del condón. Su uso fue diferencial por género y estrato socioeconómico.