Psychometric properties of the Spanish version of the Running Addiction Scale (RAS).

Despite the growing number of Spanish people who organize their lives to prepare and participate in marathons, bringing to it a very committed lifestyle that, sometimes, go in detriment of their own health. In this instrumental paper, we the adaptation and testing of the psychometric properties of the Running Addiction Scale (RAS) in Spanish. To this end, we conducted two independent studies. The aim of the first was to present the first preliminary psychometric data (pilot sample of 174 marathon runners). Explained the process of translation, adaptation and content validity of items, we carried out a statistical analysis of these, an exploration of dimensional structure and analysis of the reliability of the instrument. In the second study (sample of 975 marathon runners), the aim was to analyze the internal structure of the instrument with confirmatory procedures. The Spanish version of the RAS showed acceptable levels of internal consistency, temporal stability, inter-item correlations and total scale score. Also provides evidences of construct validity. Slight differences were obtained by sex and age. These findings support the use of the Spanish version of RAS to assess individual differences in negative addiction to running.