Does a blended learning implementation package enhance HIV index case testing in Malawi? A protocol for a cluster randomised controlled trial oleh Katherine Simon, Nora E Rosenberg, Vivian Go, Victor Mwapasa, Katie Mollan, Linda Gail Bekker, Milenka Jean-Baptiste, Tapiwa A Tembo, Sarah Rutstein, Mike Jones Chitani, Pooja T Saha, Tiwonge Mbeya-Munkhondya, Caroline Meek, Maria H Kim