The objectives of this contract are to provide assistance to the National Cancer Institute (Diagnostic Imaging Research Branch) by establishing and maintaining a data management system and by providing statistical analysis as requested by the Project Officer. These services are to be carried out in support of the NIH MRI Collaborative Working Group, a group of five contractors carrying out a comparative clinical study to compare the diagnostic accuracy of magnetic resonance imaging with that of x-ray computed tomography for seven protocols in human patients. The principal duties will include receipt and manual log-in of data forms; construction and debugging of algorithms to assist in data input, data editing for consistency and validity, monitoring, and analysis; performance of statistical analysis in accordance with outlined procedures determined by the MRI Statistical Advisory Group; and assistance in the preparation of publications and reports.