FIGURE 1 Study schematic. Initial patient data was extracted by the UNC Pharmacy Analytics team. A detailed breakdown of subjects who met the inclusion and exclusion criteria for the study is detailed. Abbreviations: 6MMP, 6-methylmercaptopurine, 6MP, 6-mercaptopurine, 6TGN, 6-thioguanine nucleotide, OSH, Outside hospital.