Ordering decision and clinic cost variation among resident physicians.

Physicians vary considerably in the services they order for their patients. We examined ordering variation among 47 resident physicians during 4,991 continuity clinic visits with patients who had specific, chronic medical problems. We ranked the physicians by their average charge per visit and grouped them into three equal categories. High-charge physicians averaged $164 per visit, medium-charge $124 and low-charge $97. In comparing the frequencies with which physicians in each group ordered a wide array of specific laboratory tests, x-ray studies, medications and miscellaneous items, we found that ordering variation among the physician groups was not confined to certain decisions or categories of services. High-charge physicians ordered a little more of nearly every item or service. Although the magnitude of ordering variation for each item was small, the sum over many items was great, suggesting that cost-containment efforts may have to focus on the "little ticket" decision-making style of expensive physicians.