*2.3. Evaluation Instruments*

The participants completed a brief sociodemographic questionnaire, through which they provided information about their age and sex, the university in which they studied, and their place of residence during the academic year. The questionnaires were distributed through Gmail, thus participants had to provide their email address, which prevented duplicates. Additional items were introduced to gather information about the training of the participants, whether they had performed the practicum, whether they felt ready for the world of work, and whether they had suffered from the disease caused by SARS-CoV-2 (COVID-19).

The main variable of this present study was psychological discomfort, and it was measured using the Kessler scale (K-10) [22].This scale shows the level of psychological discomfort of the users during the 4-week period before completing the scale. Psychological discomfort is defined as the level of stress, demoralization, malaise, and unrest perceived in oneself [23].

Since the Kessler scale (K-10) is also used as a screening method for depression and anxiety, these two variables were also measured. Anxiety is defined as a human emotion present in most mental and medical disorders that appears as a response to the perception of a threat or danger. It helps people to prepare and practice in order to improve their activity and thus adopt the appropriate caution measures against potentially dangerous situations. Clinically, anxiety is fear without a known cause [24]. On the other hand, depression is understood as a mood disorder that causes symptoms of distress and affects how the person feels, thinks, and coordinates the activities of daily living, such as sleeping, eating, and working. To be diagnosed with depression, symptoms must be present during most of the day, almost every day, for at least two weeks.

This K-10 scale was selected for its adequacy and adaptation to the study scope. It is a brief questionnaire that can be easily applied by first-level healthcare professionals. K-10 has been translated into Spanish and applied in Spain, Colombia, Mexico, and Peru, as well as in other American and European countries [22].

The Kessler instrument consists of 10 items, with 5 Likert response options each, ordered hierarchically from 1 to 5: "never, almost never, sometimes, almost always and always". The sum of the scores can range from a minimum of 10 points to a maximum of 50. The interpretation of the scores corresponds to 4 levels as follows: 10–15 points, low level; 16–21, moderate level; 22–29, high level; and 30–50, very high level [22].

K-10 has been previously validated, with high sensitivity and specificity [22]. According to the validation study, the score of the scale can be divided into 2 levels, due to its high specificity and sensitivity, for the subsequent screening for anxiety and depression. This screening also categorizes the participants based on their psychological discomfort, although with two reference levels of anxiety and depression. The cutoff points would be, on the one hand, scores of 10–20 for low affectation of psychological discomfort (anxiety and depression) and, on the other hand, scores of 21–50 for high affectation.

Aranguren and Brenlla [25] explored the discriminant validity of K–10 in psychiatric patients, also comparing the scores obtained in psychiatric patients and non-psychiatric individuals. The results showedadequate validity and reliability of the instrument, with a Cronbach's alpha of 0.91 for the patients and 0.80 for the control individuals.
