OBJECTIVES: In patients requiring frequent blood transfusions due to transfusion dependent anemia (TDA) (e.g., sickle cell disease [SCD]) and myelodysplastic syndrome (MDS), life expectancy is directly related to the quality of chelation therapy, and poor adherence to treatment increases the risk of complications and shortens survivalMETHODS: Eleven patients with TDA or MDS provided informed consent and were included in this qualitative study. Two sets of face-to-face cognitive interviews were conducted iteratively; modifications to items were debriefed in the second set. Interviews began open-endedly to elicit patients’ spontaneous experiences with ICT. Interviews were audio recorded and transcribed. An item tracking matrix documented the changes made for each item. Data analysis used ATLAS.ti software.  This study was conducted according to best practices for development and modification of PROs in an ePRO format. RESULTS: Patients were 73% (n=8) male and 27% (n=3) female with a mean age of 43 (range 14-81 years); 45% (n=5) had SCD, and 27% (n=3) had MDS. Patient spontaneous reports and cognitive debriefing responses confirmed concepts in the draft PROs and helped eliminate irrelevant items. Changes made after cognitive debriefing ensured the comprehensibility, lack of redundancy, and appropriate instructions and response options. The resultant PROs included the Compliance (2 items), GI Symptom Diary (6 items), Palatability (4 items), and modified SICT (13 items). CONCLUSIONS: Results support the content validity of PRO measures of compliance, GI symptoms, palatability, and satisfaction with ICT. These measures require psychometric validation of validity, reliability, and responsiveness before recommending their use in future clinical research.