Multistate analysis of skeletal events in patients with bone metastases.

Cancer patients with bone metastases are at increased risk of experiencing skeletal events associated with severe morbidity. Clinical trials of palliative therapies must perform rigorous and robust evaluation of new treatments on the basis of meaningful summaries of the course of skeletal events over time, while dealing with potentially high mortality rates during observation. The purpose of this article is to present a multistate model that can be easily used to reflect possible courses of the disease process, indicate how simple methods of analysis can be used to estimate clinically relevant features of the process, and contrast this approach with some of the alternative methods. The relation between the multistate approach and previously used methods is highlighted.