[DDHealth Protocol: Justification, design and implementation of a cross-sectional survey of sociodemographic health, health literacy and digital divide in 2,000 adults aged fifty to seventy-nine residing in Spain in 2022].

Socioeconomic inequalities in health persist in Spain. The DDHealth project aims to address two timely innovative aspects that have been postulated to contribute to socioeconomic inequalities in health. DDHealth aims to address two innovative and timely aspects that have been proposed to contribute to socioeconomic health inequalities. The first one is the socioeconomic digital divide, which refers to the greater capabilities and opportunities to access technology and use the internet among higher social classes compared to lower ones. The second aspect is health literacy, which refers to individuals' capacity to meet and understand the complex demands of health promotion and maintenance in modern society. The study conducted over 2,000 interviews among residents in Spain aged between fifty and seventy-nine years old from March to April 2022, using a computer-assisted telephone interviewing (CATI) approach. The questionnaire comprises four different modules: sociodemographic; digital divide; health; health literacy. The anonymized data are available through the following link: https://dataverse.csuc.cat/dataset.xhtml?persistentId=doi:10.34810/data765. DDHealth enables addressing innovative dimensions concerning the social determinants of health in Spain. The data are available to external researchers for scientific purposes upon request of a reasonable research proposal.