Adult 1 Ambulatory Care 1 Behavior Therapy 1 Cocaine 1 Cocaine-Related Disorders 1 Contingency management 1 Female 1 Humans 1 Male 1 Middle Aged 1 Outpatient substance abuse treatment Patient Compliance 1 Reinforcement (Psychology) 1 adult 1 ambulatory care 1 behavior therapy 1 cocaine dependence 1 controlled study 1 female 1 human 1 male 1 middle aged 1 patient compliance 1 procedures 1 randomized controlled trial 1 reinforcement 1