Categorical comparison of survival. (A) Surival of patients born before and after 2000. (B) Survival between sexes. (C) Survival according to economic status. (D) Survival based on distance from transfusion center. (E) Survival between patients based on age of start of transfusion. (F) Survival according to TTI status. (G) Survival based on splenectomy status. (H) Survival according to hepatitis B vaccination status. (I) Survival based on cardiac status. (J) Survival against different classes of serum iron levels. (K) Survival difference according to rate of fall of Hb per week. (L) Survival based on length of follow up at day care.