Osma, J Martinez-Garcia, Laura Peris-Baquero, Óscar Navarro-Haro, María Vicenta Gonzalez-Perez, Alberto Suso-Ribera, Carlos Implementation, efficacy and cost effectiveness of the unified protocol in a blended format for the transdiagnostic treatment of emotional disorders: a study protocol for a multicentre, randomised, superiority controlled trial in the Spanish National Health System BMJ Open 10.1136/bmjopen-2021-054286 2021 2021