A pilot study assessing the influences of charge data and group process on diagnostic test ordering by residents

Purpose. Providing charge data to resident physicians has been shown to reduce the amounts spent on diagnostic testing. This pilot study sought to determine the influences of charge data and group decision making on diagnostic test ordering by internal medicine residents. Method. In an interactive workshop, 23 internal medicine residents received a hypothetical case. They completed an 18-item questionnaire estimating charges for diagnostic tests and then "ordered" tests. The residents were then randomly divided into groups that either received charge data, received charge data after ordering tests, or received no charge data. The groups ordered tests by consensus. Tests were weighted for appropriateness (+1 to +6) and inappropriateness (-1 to -6). Analyses compared individual and group decisions and effect of availability of charge data. Results. Residents with access to charge data spent less on tests, but also had lower appropriateness scores. The appropriateness of the diagnostic workup was better by groups than by individuals, but cost more. Conclusion. Cost-containment interventions targeted towards doctors in training need to address the effect on quality of care and the influence of the group process in clinical decision making. Group diagnostic decisions may be more costly, but more appropriate.