Kidney stones and lithotripters: critical analysis of the introduction of extracorporeal shock wave lithotripsy into Canada.

It is possible for a nonpharmaceutical medical innovation to enter the mainstream of the health care system without its efficacy and effectiveness having first been established by means of a randomized controlled trial (RCT). The result of this omission may be the discreditation and abandonment of the technology or procedure but not before precious resources that could have been better used elsewhere in the health care system are absorbed. A possible example of such a misallocation of resources is the introduction into Canada of extracorporeal shock wave lithotripsy (ESWL) for the treatment of urolithiasis. We review the development and diffusion of ESWL and recommend ways in which the deficiencies in regulating the introduction of new medical technologies can be corrected.