*2.6. Ethics*

The researchers had no conflicts of interest. Ethical approval was obtained from the Research Ethics Committee of the University of Cantabria, Spain (CE Proyectos 13/2020). The treatment of the data guaranteed their confidentiality and their exclusive use for this project, respecting the legislation in force. At the beginning of the questionnaire, there was a specific box for giving consent to participate.

#### **3. Results**

#### *3.1. Descriptive Analysis of the Sample*

A total of 1562 people responded (response rate = 20.88%). Women accounted for 87.5% of the sample. The mean age was 21.5 ± 5.7 years. Up to 76.8% resided in urban areas. Participation of NS was equal for all four academic years. Overall, 67.9% did not suffer from any chronic disease, and 86.3% were non-smokers. In relation to COVID-19, only 9% had suffered from the virus, confirmed with a PCR test. For 52.8%, someone in their environment had suffered from the disease and of these, 6.9% died from it (Table 1).

**Table 1.** Sociodemographic variables of the sample and questions related to COVID-19.


† Variable not answered by the totality of the sample. \* Other diseases such as asthma, hypertension, hypothyroidism, diabetes, hyperlipidemia, cancer, bronchitis, etc.
