ABSTRACT
In Chapters 1-4 we have repeatedly noted that the clinician, when dealing with a new patient, has often to draw heavily on previous experience. In this chapter we seek ways in which we may usefully quantify and summarize such experience. In particular, we try to find statistical counterparts to commonly voiced ideas such as ‘normal range’, ‘within previous experience’ and ‘completely atypical’. We shall therefore be assuming that there exists some reliable and useful set of past observations or measurements. We leave to the next chapter any discussion of the problems that have to be considered in achieving this aim of a reliable and useful data set.
