“…It was used as an indicator of their socioeconomic status (SES), taking into account the classification suggested by Domingo-Salvany, Regidor, Alonso, and Alvarez-Dardet (2000), which defines nine categories of SES. This classification has been used in several epidemiological studies with Spanish populations to estimate the SES of the population (see, e.g., Huguet & Miró, 2008; Macenlle García, Gayoso Diz, Sueiro Benavides, & Fernández Seara, 2006; Miró et al, 2007).…”