Mwansa Mbulo; Penda Annie. Theoretical and Conceptual Frame Work for Factors That Lead to Poor Performance for Learners With Hearing Impairment in the National Examination at Grade Nine (9): A Case of ChilesheChepela Special School and Musakanya Special Unit in Kasama and Mpika District. Int. j. res. inf. sci. appl. tech. 2022, 2, 11-22.