An implementation trial to mAnage siCkle CELl disEase through incReased AdopTion of hydroxyurEa in Nigeria (ACCELERATE): Study protocol - Emmanuel Peprah; Joyce Gyamfi; John Patena; Hazal Kayalioglu; Tania Hameed; Gbenga Ogedegbe; Hyungrok Do; Dike Ojji; Deborah Adenikinju; Tayo Ajaye Oba; Maxwell Nwegbu; Hezekiah Isa; et al. (PLoS ONE)