A research project carried out with young people between 10 and 24 in 2002 showed a life prevalence of 11 out one thousand Finally, a recent study carried out in 2008 shows statistics that display a life prevalence of 19 out of one thousand and annual and monthly prevalence of two out of one thousand 6.
Finalmente un reciente estudio realizado en el 2008 da cuenta de cifras que alcanzan una prevalencia de vida del diecinueve por mil y anual y mensual del dos por mil Tabla 1.