One-month repeatability of alcohol metabolism, sensitivity and acute tolerance.

Subjects (N = 34) in the Colorado Alcohol Research on Twins and Adoptees (CARTA) were brought back between 30 and 60 days after their initial testing to be retested on all the CARTA procedures. As before, subjects were given a dose of alcohol (.8 g/kg of body weight) calculated to bring their blood alcohol level (BAL) to near 100 mg/dl. Additional doses were given at the end of each of the next 2 hours to maintain their BAL near peak for approximately 3 hours. Repeatability (test-retest correlation) for alcohol clearance rate was near 0, with repeatabilities between .40 and .55 for peak BAL, time-to-peak BAL, average session BAL and relative volume of alcohol distribution. Repeatabilities of prealcohol baseline scores were generally high (median, .71) for the CARTA battery of physiological, motor coordination, perceptual speed and reaction time measures, but were only low to moderate for sensitivity scores (median, .27) and acute tolerance scores (median, .25) calculated on these measures. There was some evidence that repeatabilities for alcohol metabolism, sensitivity and acute tolerance were lower for women than for men.