Resumen de Confiabilidad y validez de la escala de depresión CES-D en un censo de estudiantes de nivel medio superior y superior, en la Ciudad de México
Catalina González Forteza, Cuauhtemoc Solís Torres, Alberto Jiménez Tapia, Itzel Hernández Fernández, Alejandro González González, Francisco Juárez García, María Elena Medina-Mora Icaza, Héctor Fernández Varela Mejía
- español
Introducción La depresión y sus manifestaciones sintomatológicas son parte de los principales problemas de salud entre la población mundial y su impacto en la vida productiva ha aumentado con respecto a otras enfermedades.
En México, esta tendencia y sus consecuencias negativas en el desarrollo hacia la adultez justifican la necesidad de atenderla y prevenirla. A través de instrumentos de tamizaje válidos y confiables como la Escala de Depresión del Centro de Estudios Epidemiológicos (Center for Epidemiological Studies of Depression Scale: CES-D) diseñada en 1977 por Radloff, ha sido posible detectar posibles casos clínicos de depresión en diversos estudios con adolescentes escolares.
Sin embargo, hasta ahora no se había documentado su comportamiento en una población de estudiantes a gran escala.
Método El levantamiento de la información se realizó en agosto de 2009, previo al inicio del ciclo escolar. Se obtuvo información de 57403 alumnos, de los cuales 47.5% fueron hombres y 52.5% mujeres, con una edad promedio de 17 anos (�}2.7). Instrumento. La CES-D se incorporo en los formatos del Examen Medico Automatizado (EMA) que se utilizaron para realizar el levantamiento censal entre los alumnos de nuevo ingreso a bachillerato o licenciatura.
Resultados Consistencia interna y validez de constructo. La consistencia interna de la escala global mostro un indice satisfactorio (�¿=0.83). Los indices de confiabilidad fueron adecuados para todos los grupos de edad. El analisis factorial con extraccion de componentes principales y rotacion oblicua arrojo una estructura de cuatro factores con valores Eigen mayores a uno, que explican 54.1% de la varianza;
los coeficientes de consistencia interna y concordancia teorica resultaron satisfactorios: Afecto deprimido, Afecto positivo, Somatizacion e Interpersonal (como un indicador integrado por solo dos reactivos).
Validez concurrente por medio de grupos contrastados. En la prueba de grupos contrastados se compararon los puntajes globales de la CES-D que se situaron por debajo del percentil 25 versus aquellos por arriba del percentil 75. Se utilizo una comparacion de promedios de Mann-Whitney, que mostro diferencias estadisticamente significativas entre los cuartiles contrastados (z=-144.121, p<.001).
Validez externa. Se analizo mediante su asociacion con la Escala de Expectativas de Vivir-Morir de Okasha (que tambien se aplica en el EMA), obteniendo una correlacion positiva y significativa entre quienes tuvieron sintomatologia depresiva elevada y quienes manifestaron deseos de morir (r�³=0.325, p=.000).
Deteccion de sintomatologia depresiva elevada. La definicion operacional de la sintomatologia depresiva elevada se definio con el punto de corte (PC) de la CES-D con base en la media mas una desviacion estandar (PC. 16) con lo que se detecto una frecuencia de sintomatologia depresiva elevada de 14.7% (n=8,197): 11.1% en varones y 17.9% en mujeres.
Conclusiones Los resultados muestran que en poblaciones tan grandes como la del presente estudio, la CES-D es una herramienta útil y adecuada, breve y fácil de aplicar y analizar para establecer un monitoreo que dé respuesta a una de las necesidades más apremiantes en la población escolar: la detección de la sintomatología depresiva elevada como un aspecto importante del malestar emocional. Sirve, además, para determinar la magnitud de la problemática y arribar a su prevención y, de ser el caso, instrumentar acciones para su tratamiento. La relevancia de los resultados obtenidos radica en que se trata de población escolar que puede llegar a requerir atención y prevención oportunas en salud mental en etapas tempranas de la enfermedad, incluso antes de la confirmación diagnóstica en los servicios especializados.
Esta detección deriva en beneficios para la población escolar y en estrategias funcionales de atención adecuada y costo-efectivas
- English
Introduction Depression and its symptoms are becoming one of the most important health problems worldwide. The impact of depression on the productive life of people, and the burden it represents because of its co-morbidity, is growing. Some authors estimate that depression is the second cause for the global loss of years of healthy life and the first one in developed countries.
An increasing proportion of teenage population has mental health issues. Depression and its symptoms are among the most common, but they are not an epidemic problem yet, although spread enough as to maintain interest in its current impact and in its negative consequences over individual health.
Depression has a prominent place among mood disorders in Mexico (4.5%), and women are who mostly suffer it (5.8%), which has remained consistent over time.
Different difficult situations occur during adolescence along with depression, depressive mood, and depressive symptoms. This situation may be related to changes and processes that occur during this period when individuals cope with situations they cannot handle, which in turn become stressful. Therefore, it is necessary to study and to work with adolescents in order to be able to differentiate affective, cognitive, somatic, and behavioral expressions, which are proper to this stage, from those possibly caused by an illness that could have negative consequences.
Adolescent depression influences mood and the way individuals live unpleasant or annoying experiences, thus it affects almost every aspect of life and becomes a risk factor for psychiatric and behavioral problems. However, there are some areas that need more research, for example: the specific characteristics and expressions of the problem including gender comparisons and using designs with special groups.
Data show that depression is growing in adolescents; therefore it is a priority to work on detection and prevention to reduce its impact on mental health and to develop cost-effective intervention strategies. One way to do this is using valid-reliable screening tools because they are cheap, and methodologically-logistically useful.
The Center for Epidemiological Studies Depression Scale (CES-D) has been used in different studies with Mexican adolescents, and has proven to have good psychometric characteristics. The CES-D has never been used with an entire population in a great scale study. The objective of this paper is to measure the validity and reliability of the scale (construct, concurrent, and external validity, as well as internal consistency) in a population of high school and college freshman students from Mexico City.
Method Design. The study was a census made with high school and college freshman students during 2009. Data were collected in 22 schools.
Population. A sample of 58568 students participated in the census. The mean age was 1 7 years old (±2.7). Most of the students lived in homes with one to four other persons at the moment of the study (55.4%); 86% said that only their father worked at that moment, and 59.4 said that only the mother; 79.7% of the students lived with both parents, and 1 7.9% only with their mother; 57403 students (98.0% of the population) completed the CES-D in the age range of 14-24 years: 27264 (47.5%) men, and 30139 (52.5%) women.
Instrument. The Automated Medical Examination (Examen Médico Automatizado-EMA) is a diagnostic questionnaire designed by the General Directorate of Medical Services (Dirección General de Servicios Médicos) of the Universidad Nacional Autónoma de México (UNAM). It is a questionnaire with four self-report forms that collect information about the physical and mental health, the family, and the general context of every student. This information is used to create a diagnosis of vulnerability and a predictive profile for developing prevention programs, as well as research protocols that help in promoting a culture for health care. The CES-D was included for the measurement in 2009.
Results Overall internal consistency was adequate (α=.83). Internal consistency was tested by sex; the coefficient was higher for women (α=.84). Factor analysis generated a four-factor solution (explained variance 54.1%); each factor had good internal consistency and theoretical agreement.
The scale showed a significant discriminative power for opposite scores (z=-l44.121, p<.001), and a positive significant correlation with the Okasha Suicidality Scale (rΦ=.325, p = .000).
A cut-off point of 16 or higher was established to identify students with high depressive symptomatology. 14.7% of the participants in this study had high depressive symptomatology (11.1% men, 1 7.9% women).
Conclusions The CES-D is a valid and reliable epidemiological instrument for different populations. Since depression is a complex and dynamic phenomenon, it is important to evaluate the psychometric properties of any instrument used to measure it.
The results of this study showed that the CES-D maintains its internal consistency as well as good concurrent-external validity. Coefficients are higher for women and they increase with age; thus, it would be necessary to refine some aspects to measure younger subjects in a more consistent manner. The data proved that CES-D is a useful instrument for distinguishing different levels of depressive symptomatology; this is relevant because the scale is often used in collective contexts, allowing systematic monitoring of depression with good cost-effective results. Monitoring is also important to keep acceptable levels of emotional wellbeing in student population.
Development and refinement of instruments such as the CES-D would potentially lead to opportune and reliable detection of adolescents who may be at risk for suffering mental health problems. This would facilitate implementing more stable and continuous prevention and attention programs to reduce the negative impact of depression in the short term.
