Opioids and fibromyalgia: frequency of use and factors associated with increased consumption in patients remitted to a tertiary care center - Rivera, J.; Molina-Collada, J.; Martínez-Barrio, J.; Serrano-Benavente, B.; Castrejón, I.; Vallejo, M.A.; Álvaro-Gracia, J.M. (BMC Musculoskeletal Disorders, 2024)