One of the trickiest problems in Medicine is trying to identify whether an unusual trend in mortality rates is an indication of an incompetent physician, or worse, a physician who is actively killing patients.
I have not read the following article, but it proposes the use of control charts for monitoring mortality rates. From the abstract, it looks like a promising approach.
- Steiner SH, Cook RJ, Farewell VT, Treasure T. Monitoring surgical performance using risk-adjusted cumulative sum charts. Biostatistics 2000: 1(4); 441-52. Available in pdf format.
A recent BMJ article
- BMJ 2005;330:329 (12 February), doi:10.1136/bmj.330.7487.329. Available in html format or pdf format.
discusses the use of this type of control chart in a particular hospital that had a hospital standardized mortality ratio of 130, which was “the highest of all main acute hospitals in England (30% above the value for England as a whole, which is 100)”. In response, the authors used control charts to reduce this rate to 92.8, with the largest reductions in circulatory diseases and respiratory diseases.