title: Monetary contracts in weight control: effectiveness of group and individual contracts of varying size.
mesh_terms: D000328:Adult; D001521:Behavior Therapy / Q000379:methods*; D004038:Diet, Reducing / Q000523:psychology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000523:psychology / Q000628:therapy*; D014040:Token Economy