<prompt> Translate the following text to EnglishUchunguzi wa kesi ya jumla ya nyuma ulifanywa na Benki ya Dunia katika uchunguzi wake wa masomo manne ya kesi ya kina ya ufanisi wa programu za elimu.  <response>: A retrospective cumulative case study was conducted by the World Bank in its examination of four in-depth case studies of the effectiveness of educational programs. 