IEC/TR 60493-2:2010(E) provides an account of the work done in designing and validating the statistical procedures for operations on censored groups of normally distributed data. The relationship to similar operations on complete (uncensored) data is examined, and it is shown that "mixed" or wholly uncensored data groups may be analysed in the same way as wholly censored ones. Attention is drawn to the effect of some variation of group size and extent of censoring, as well as the effect of non-uniform data group sizes.