RESUMEN
Myeloma is a hematologic malignancy in which there is monoclonal proliferation of bone marrow plasma cells that produce abnormal proteins. Reviewing the medical records of patients admitted to Dr.Shariati and Imam Khomeini Hospitals of Tehran University of Medical Sciences from 199 1-2000, we assessed distribution of epidemiologic and clinical parameters of patients with Myeloma and for each parameter we evaluated the missed data percentage as an index of active data collection. Among the epidemiologic parameters only age and sex had no missing data. For smoking, missing data were 22.9% and in other parameters there were more than 90% missing data. For clinical parameters, missing data percentages were between 46.2% and 93.1%. Establishing a documented system for object oriented data collection based on specific epidemiologic and clinical parameters is essential for optimum prevention and management of Myeloma