The Tyranny of Metrics

by Jerry Z. Muller

Physician report cards create as many problems as they solve. Take the phenomenon of risk-aversion. Numerous studies have shown that cardiac surgeons became less willing to operate on severely ill patients in need of surgery after the introduction of publicly available metrics. In New York State, for example, the report cards for surgeons report on postoperative mortality rates for coronary bypass surgery, that is, what percentage of the patients operated upon remain alive thirty days after the procedure. After the metrics were instituted, the mortality rates did indeed decline—which seems like a positive development. But only those patients who were operated upon were included in the metric. The patients who the surgeons declined to operate on because they were more high-risk—and hence would bring down the surgeon’s score—were not included in the metrics.