The behavior-therapeutic use of contingency contracting to control an adult behavior problem: weight control.

Items considered valuable by the subject and originally his property were surrendered to the researcher and incorporated into a contractual system of prearranged contingencies. Each subject signed a legal contract that prescribed the manner in which he could earn back or permanently lose his valuables. Specifically, a portion of each subject's valuables were returned to him contingent upon both specified weight losses and losing weight at an agreed-upon rate. Furthermore, each subject permanently lost a portion of his valuables contingent upon both specified weight gains and losing weight at a rate below the agreed-upon rate. Single-subject reversal designs were employed to determine the effectiveness of the treatment contingencies. This study demonstrated that items considered valuable by the subject and originally his property, could be used successfully to modify the subject's weight when these items were used procedurally both as reinforcing and as punishing consequences. In addition, a systematic analysis of the contingencies indicated that punishing or aversive consequences presumably were a necessary component of the treatment procedure.