Each of the study Cores (PFT, Imaging, Biorepository, Genome-Wide Analysis, Candidate Genotyping, and the DCC) developed plans for quality control of data handling. The DCC is the central storage site for all study data and leads the QA program for data entry, including range-checking of data on entry, multi-variable validation and monthly reports on data quality, and maintenance of an auditing record of all data changes. Each study center is informed weekly about out-of-range data so problems can be resolved rapidly. Data identified as out of range are reviewed by the Quality Control Committee and when necessary by the Adjudication Committee.
