Table 2.

Responses to Text Message Assessments of Daily Methamphetamine Use, Usefulness of Messages, and Peak Daily Craving

Text Message Assessments	Active (%)	Placebo (%)	Active* (%)	Placebo* (%)	Efficacy Results	95% CI
Overall Response Rate (# Responded to/# Sent)	179/213 (84%)	160/215 (74%)	179/195 (92%)	160/173 (92%)	n/a
Daily Self-Reported Use	32/35 (91%)	26/35 (74%)	32/32 (100%)	26/28 (93%)	1 day use (total) in active phase & 2 days use (total) in placebo phase	n/a
Usefulness Ratings	119/143 (83%)	110/145 (76%)	119/131 (91%)	110/117 (94%)	6.6 OR**	[2.2, 19.4]
Daily Peak Craving***	28/35 (80%)	24/35 (69%)	28/32 (88%)	24/28 (86%)	Mean 3.3 in placebo phase; 40% higher in the active phase	[2.8, 3.8]; [9%, 80%]

^*Excludes from the denominators post Day 5 messages for participant who discontinued responding prematurely due to his arrest.

^**Odds of messages being rated as “very” or “extremely” useful (versus “not at all,” “slightly” or “moderately”).

^***On a scale of 0–10, where 0 is “no craving” and 10 is “most ever experienced”