Issues of software reliability in medical systems

It is shown that the traditional methods of ensuring quality (i.e. those that focus on testing) do not necessarily yield software of prescribed quality. Similarly, more advanced methods, such as those that advocate mathematical verification during development and the use of fault-tolerant structures at execution time, are also not able to assure dependable performance. It is shown that, for safety-critical medical systems that are required to achieve very high quality levels, post-development assurance of a specific level of quality is infeasible. It is concluded that safety-critical systems that depend on computers should be deployed only with the greatest of care.<>