## 2 Background
In the absence of an instrument that allowed measuring the different types of motivation present in the theory of self-determination, [PERSON], [PERSON], [PERSON], and [PERSON] [16] developed and validated in French the Echelle de Motivation en Education (EME). Validation studies revealed that EME had satisfactory levels of internal consistency, with a mean in Cronbach being alpha of 0.80 and high rates of temporal stability, and a mean of 0.75 in the test-retest correlation, after a period of one month [16]. The results of the confirmatory factor analysis confirmed the structure of seven EME factors and the construct validity was tested through correlations between the seven subscales of the instrument. In addition, EME has been able to predict educational dropout [13]. The translation of EME into Spanish was performed using the parallel back translation procedure [17] as a first step and secondly, the items obtained above were evaluated by a committee formed by the subjects who participated in the translation process and two expert teachers in the psychology of motivation. They selected the items that had maintained the original meaning and prepared the format and instructions of the scale in an identical way to the original version [1]. Thus, the Spanish version is called the Educational Motivation Scale (EME-E). The Educational Motivation Scale has been validated in Spanish-speaking countries such as Mexico [15] and Paraguay [18]. The results have revealed that the EME-E has adequate levels of reliability and validity factorial consonance with the results of the original version and the English version. Regarding the reliability of the scale, the internal consistency of the subscales has been adequate and very similar to those found in the original version [16] and in the English version [11], as well as in the validation performed in a US sample [19]. Youth is a very important stage in people lives, in which very important development processes occur for the transition to adulthood. Among them, young people finish their educational training, join the world of work, can participate as citizens, establish emotional relationships, as well as face risk behaviors such as drug and alcohol use [20]. This period can be especially challenging and vulnerable for individuals with a greater emotional reactivity to stress, which can play a significant role in the development of anxiety and depression disorders [21]. Depression and anxiety are very different, but in clinical practice and research specifically overcome, since they usually appear several times [22]. To improve the distinction of anxiety and depression, the Depression, Anxiety and Stress Scales (DASS) were created [23]. The DASS was made up of three scales that measure depression, anxiety, and stress separately [24]. Considering that depression and anxiety represent dimensions and not categories, non-clinical samples were predominantly used in the development of DASS, in which preliminary tests showed that DASS had adequate convergent and discriminant validity [22]. Some studies have directly tested the validity of DASS construction, both in clinical and non-clinical samples, in young people and adults [24; 25; 26; 27]  
In later years, an abbreviated version of the instrument (DASS-21) was developed for situations in which a shorter application is needed [22]. It was translated and validated in the Hispanic population [28] and its factor structure and psychometric properties have been analyzed, finding a three-factor structure through confirmatory factor analysis and exploratory factor analysis [22]. In the Hispanic population, DASS-21 has been found to show an acceptable fit for a three-factor model and important correlations between scales [28]. In Chile, a validation study of DASS-21 [29] was carried out in middle school students, with an average age of 15 years.