The present study had two aims : ( @ ) compare standard care ( SC ) for smoking ( four weeks of brief counseling and monitoring ) to SC plus prize-based contingency management ( CM ) , involving the chance to earn prizes on days with demonstrated smoking abstinence ( carbon monoxide ( CO ) @ ppm ) ; and ( @ ) compare the relative efficacy of two prize reinforcement schedules-one a traditional CM schedule , and the second an early enhanced CM schedule providing greater reinforcement magnitude in the initial week of treatment but equal overall reinforcement .