A person’s LR can be measured by administering an alcohol challenge, either through oral ingestion or intravenously, and recording the individual’s level of reaction over several hours. Such alcohol-administration paradigms are time consuming and costly, making it difficult to evaluate large numbers of subjects (Schuckit et al., 1997a). LR can also be measured by the retrospective Self-Report of the Effects of alcohol (SRE) questionnaire, in which participants estimate the number of standard drinks usually required to experience up to four different effects of alcohol (feel an effect; feel dizzy or slurring speech; stumble or walk in an uncoordinated manner; pass out or fall sleep) at three time periods (first 5 times of drinking, the period of heaviest drinking, and the most recent three months of consumption). SRE scores and LR measured during an alcohol challenge are correlated (r = 0.3-0.6), suggesting that the easier to collect SRE can be used in large-scale studies to measure LR (Schuckit et al., 1997a, Schuckit et al., 2009b, Schuckit et al., 1997b). SRE scores also have an one year test-retest correlation between 0.72-0.82 and
