Table 2.

Demographic Characteristics and Descriptive Statistics for Caffeine, Alcohol and Caffeinated Alcoholic Beverage Use Patterns as a Function of Experimental Group.

	Group 1, no caffeine and no expectancy	Group 2, caffeine and caffeine expectancy	Group 3, no caffeine and caffeine expectancy	Group 4, caffeine and no expectancy
	n = 37	n = 35	n = 35	n = 39
	Mean (SD)	Mean (SD)	Mean (SD)	Mean (SD)
Age	24.27 (2.21)	24.03 (2.60)	24.03 (2.20)	24.08 (2.38)
Caffeine*
Frequency	5.64 (2.07)	5.49 (1.96)	5.22 (2.17)	5.38 (2.02)
Quantity	1.85 (.84)	1.82 (.85)	2.09 (1.30)	1.69 (.81)
Alcohol
Frequency	3.92 (1.64)	3.63 (1.65)	3.83 (1.44)	4.44 (1.76)
Quantity**	3.81 (1.61)	3.39 (1.54)	3.38 (1.68)	3.90 (1.76)
Caffeinated Alcoholic Beverages
Frequency	1.81 (1.58)	2.03 (2.41)	1.60 (1.61)	2.18 (2.20)
Quantity***	1.66 (1.11)	1.66 (.94)	1.65 (.78)	1.63 (.92)
	n (%)	n (%)	n (%)	n (%)
Caffeine Dependent	10 (27)	19 (54)	16 (46)	16 (41)
Smoking	11 (30)	10 (29)	9 (26)	9 (23)
Female	19 (51)	18 (51)	18 (51)	19 (49)
Caucasian	23 (62)	25 (71)	22 (63)	25 (64)

Note. Frequency = number of days consumed in an average week in the past 3 months; Quantity = average number of beverages consumed per use day in an average week in the past 3 months.

^*Caffeinated beverages could include coffee, tea, soda and energy drinks; mg of caffeine consumption varies across beverage types.

^**Standard number of alcoholic drinks.

^***N = 106