Background:
To date, very few smoking cessation interventions targeting waterpipe tobacco smoking have been reported worldwide.

Methods:
Thirty-one adults completed the study. Participants were adults 18 years of age and older who smoked tobacco using a waterpipe three times or more per week for the past one year, did not smoke cigarettes, and were not planning on quitting waterpipe tobacco smoking.
Design: A two-group, repeated measures (10 study visits on Mondays and Thursdays) design was used. Participants were randomly assigned to either the contingent (n = 19) or non-contingent (n =20) study arms.
Intervention: Contingent participants received monetary incentives based on negative salivary cotinine results. Earning incentives started at $14 and increased by $ 0.50 for a maximum $192.50. Non-contingent participants earned incentives independent of salivary cotinine results. Participants in both study arms had the opportunity to earn the same amount of money. The primary study outcomes were biochemically verified prolonged abstinence and 7-day point prevalence.

Results:
The prolonged abstinence rate in the contingent and non-contingent groups were 61% and 6%, respectively, (p ˂ 0.001). The 7-day point prevalence in the contingent and non-contingent were 47% and 5%, respectively, (p = 0.003). The odds of abstinence were 17.10 (95% CI=1.89, 154.84) times greater for the contingent group than for the non-contingent group.

Conclusions:
The preliminary results support further examination of contingency management as a strategy for initially motivating unwilling waterpipe smokers to quit.