Rewarding people with money or prizes for abstaining from their drug of choice helps them stay in treatment-and it appears the prizes' worth also matters-according to studies presented at APA's 2006 Annual Convention by Nancy Petry, PhD, professor of psychiatry at the University of Connecticut Health Center.
In a 2000 study published in The Journal of Consulting and Clinical Psychology (Vol. 68, No. 2, pages 250-257), Petry tested a reward-based-or contingency management (CM)-intervention called "the fishbowl" with 42 alcohol-dependent outpatients, half of whom were randomly assigned to a CM group. Both CM participants and controls received weekly group therapy sessions and breath tests-daily for four weeks, then weekly for the next four.
When CM patients tested negative for breath alcohol content, or when they completed a goal-related activity like writing a résumé, they drew a slip of paper from a fishbowl to possibly win a prize. The prizes included small items, such as bus tokens or socks, valued at about $1, large items worth about $20, such as watches and pots and pans, and a jumbo prize worth around $100, such as a window air conditioning unit or DVD player. Eighty-four percent of patients in the CM group stayed in treatment for the entire eight-week study versus 22 percent of patients who received standard care.
In addition, the value of the fishbowl prizes appears linked to the intervention's success, said Petry. In a 2004 paper published in Addiction (Vol. 99, No. 3, pages 349-360), Petry assigned 120 people with cocaine-dependencies to a standard treatment group, a CM group that received prizes averaging $80 or a CM group that received prizes worth $240 on average. The greater the worth of the prizes, the more effective the treatment program, she said.
"It was necessary to provide larger magnitude prizes to have a significant improvement relative to standard care," said Petry.
--E. Packard
