<qa>  What is the dose that will be administered during these visits?- Subjects will then return every 2-4 weeks for routine blood transfusions and as required for the management of Thalassemia. To ensure compliance, study medications will be administered by study personnel during these routine visits. Vitamin D supplies will be packaged according to one week worth requirement, i.e. as 1,000 IUday x 7days7,000 IU for the intermediate vitamin D group. The dose that will be administered during these visits will depend on the interval between transfusions, i.e. 7,000 IU x 2weeks, for a subject of the intermediate dose who is transfused every two weeks. 