2.2. Participants and Setting

The inclusion criteria for the participants were as follows: residents of Alcalá de Henares, at least 18 years of age, with full capacity to answer questions and follow instructions, who agreed to participate in this research study. The exclusion criteria were established by default.

The data were collected by students on the bachelor’s degree course in Nursing at the University of Alcalá. The questionnaire was assigned at random, using a telephone directory, and stratified by districts in the municipality of Alcalá de Henares (N = 198,945 inhabitants). No follow-up of the participants took place.

The sample size was 611 inhabitants, due to protocol compliance, and the participants were aged from 15 to ≥65 years, in Alcalá de Henares (Madrid). The interviews took place between 15 February and 30 April 2018, by telephone, in person, and online. Based on a 95% bilateral confidence interval, at least 580 surveys were considered sufficient to address a 50% indeterminacy, with an error of ± 7.2%.