Background: Prevention of depression must address multiple risk factors. Estimating overall risk across a range of putative risk factors is fundamental to prevention of depression. However, we lack reliable and valid methods of risk estimation. This protocol paper introduces PREDICT, an international research study to address this risk estimation.Methods/design: This is a prospective study in which consecutive general practice attendees in six European countries are recruited and followed up after six and 12 months. Prevalence of depression is assessed at baseline and each follow-up point. Consecutive attendees between April 2003 and September 2004 who were aged 18 to 75 were asked to take part. The possibility of a depressive episode was assessed using the Depression Section of the Composite International Diagnostic Interview. A selection of presumed risk factors was based on our previous work and a systematic review of the literature. It was necessary to evaluate the test-retest reliability of a number of risk factor questions that were developed specifically, or adapted, for the PREDICT study. In a separate reliability study conducted between January and November 2003, consecutive general practice attendees in the six participating European countries completed the risk factor items on two occasions, two weeks apart. The overall response rate at entry to the study was 69%. We exceeded our expected recruitment rate, achieving a total of 10,048 people in all. Reliability coefficients were generally good to excellent.Discussion: Response rate to follow-up in all countries was uniformly high, which suggests that prediction will be based on almost a full cohort. The results of our reliability analysis are encouraging and suggest that data collected during the course of PREDICT will have a satisfactory level of stability. The development of a multi-factor risk score for depression will lay the foundation for future research on risk reduction in primary care. Our data will also provide the necessary evidence base on which to develop and evaluate interventions to reduce the prevalence of depression.

Background Few South American studies have examined current prevalence rates of psychiatric disorders.

Resumen: La OMS coloca a Chile entre los países con mayor carga de morbilidad por enfermedades psiquiátricas (23,2%) en el mundo. La depresión mayor y los trastornos por consumo de alcohol ocupan el primer y segundo lugar en las discapacidades atribuidas entre adultos. Casi un tercio de la población mayor de 15 años ha sufrido un trastorno psiquiátrico en su lapso de vida y un 22,2% ha tenido uno durante el año pasado. Los trastornos de ansiedad son los más prevalentes, seguidos por depresión mayor y trastornos por consumo de alcohol. Solo el 38,5% de quienes han sido diagnosticados reciben algún tipo de servicio de salud mental, ya sea de un especialista o un médico de atención primaria. En niños y adolescentes, la prevalencia de cualquier trastorno psiquiátrico es de 22,5% (19,3% para niños y 25,8% para niñas). Estos trastornos son principalmente de ansiedad y disruptivos. La prevalencia es más alta entre niños de cuatro a once años de edad (27,8%) que entre aquellos de 12 a 18 años, y esta diferencia se debe principalmente a trastornos disruptivos. La prevalencia de trastornos de ansiedad es la segunda más alta, aunque menos asociada con discapacidades, mientras que muchos niños y adolescentes con trastornos afectivos están discapacitados y solo un quinto de las personas con necesidad de servicios buscan alguna forma de asistencia. Casi un cuarto de aquellos que usan los servicios no presentaron diagnóstico psiquiátrico durante el año pasado. La comorbilidad ocurre en el 27% de aquellas personas que presentan trastornos, pero solo el 7% tienen tres o más diagnósticos. No abordar la brecha

Psychiatric disorders that appear during childhood or adolescence should be a public health priority. To report the results of a national representative survey in the Latin American region examining the prevalence of DSM-IV psychiatric disorders in children and adolescents. Subjects aged 4 to 18 years were selected using a stratified multistage design. The Diagnostic Interview Schedule for Children Version IV (DISC-IV) was used to obtain 12-month DSM-IV diagnoses, and was supplemented with questionnaires examining family risk factors, socioeconomic status and service use. A sample of 1558 children and adolescents (51% males) was evaluated. Fifty three percent of the sample were children aged 4 to 11 years and the rest were adolescents aged 12 to 18 years. The prevalence rate for any psychiatric disorder without impairment was 38.3% (33.5% for boys and 43.3% for girls). The prevalence rate was higher among children as compared to adolescents (42.9% and 33.2%, respectively). A third of participants receiving a diagnosis sought some form of assistance. Nearly a quarter of those using services, did not have a psychiatric diagnosis in the past year. Comorbidity was found in 27% of those with a disorder, but only 7% had three or more diagnoses. The prevalence of psychiatric disorders in Chile is high among children and adolescents. This study highlights the increasing need to re-evaluate mental health services provided to children and adolescents in our country.