Jin, X., Kinner, S., Hopkins, R., Stockings, E., Courtney, R., Shakeshaft, A., … Dolan, K. (2018). Brief intervention on Smoking, Nutrition, Alcohol and Physical (SNAP) inactivity for smoking relapse prevention after release from smoke-free prisons: a study protocol for a multicentre, investigator-blinded, randomised controlled trial. BMJ Open, 8(10), e021326. https://doi.org/10.1136/bmjopen-2017-021326 (Original work published 2018)