To meet the increasing needs of researchers at large, NSDUH public use files (PUFs) have been created using a statistical disclosure control technique called MASSC to protect confidentiality of the data. MASSC stands for Micro-Agglomeration, Substitution, Subsampling, and Calibration (Singh, 2002; Singh, Yu, & Dunteman, 2003; Singh, Yu, & Wilson, 2004). MASSC has been successfully used to create NSDUH PUFs since 1999 to control both
disclosure risk and information loss. Although quality assessment was conducted before releasing each NSDUH PUF to the general public, no formal report had been published until now to document the impact of disclosure treatment on the quality of NSDUH data.