%0 Journal Article %T Study protocol for the optimisation, feasibility testing and pilot cluster randomised trial of Positive Choices: a school-based social marketing intervention to promote sexual health, prevent unintended teenage pregnancies and address health inequalities in England %A Alison Hadley %A Catherine H. Mercer %A Chris Bonell %A Diana Elbourne %A Elizabeth Allen %A G. J. Melendez-Torres %A Honor Young %A Maria Lohan %A Rona Campbell %A Ruth Ponsford %A Steve Morris %J Archive of "Pilot and Feasibility Studies". %D 2018 %R 10.1186/s40814-018-0279-3 %X The online version of this article (10.1186/s40814-018-0279-3) contains supplementary material, which is available to authorized users %K Teenage pregnancy %K Sexual health %K SRE %K RSE %K School intervention %K Adolescent %K Cluster randomised trial %U https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5964886/