The number of individuals included in the analysis of the quantitative factor score QUANTDEP was 2,183 (47% male). The confirmatory one factor model fit the data well in COGA (CFI=0.96; RMSEA=0.07) and in the replication sample, SAGE (CFI=0.98; RMSEA=0.07), supporting our proposed unidimensional conceptualization of dependence criteria for alcohol, cannabis, cocaine and opioids. Factor loadings in the COGA sample ranged from 0.67 (alcohol dependence criterion desire to cut down) to 0.99 (for several cocaine dependence criteria) and were highly consistent across COGA and SAGE. In general, factor loadings for alcohol and cannabis dependence criteria were lower, and ranged between 0.67-0.85 while those for cocaine and opioids were uniformly high (0.84-0.99). Data across drug classes and across criteria loadings (and standard errors) for all 7 criteria for the 4 substances are available in Supplemental Material Figure 1.
