SUMMARY The problem of selecting those treatments which are equivalent (or bioequivalent) to a control treatment is investigated by using single‐step, step‐down and step‐up multiple‐testing procedures. For each of the tests considered the null hypothesis is that of non‐equivalence and the hypotheses are rejected in either a single step or a stepwise fashion while controlling the family wise error rate. The single‐step procedure is based on ‘expanded’ confidence intervals, as discussed by Bofinger, the step‐down procedure is based on the method of Naik and the step‐up procedure on the method of Dunnett and Tamhane. Almost all the critical constants used in the procedures are based on tables already published.

The bioequivalence (or equivalence) of a number of experimental treatments when compared with a control is studied for the case of normal distributions with common (possibly unknown) variance. For the case of known variance and equal sample sizes on experimental treatments an upper confidence bound is obtained for the maximum difference between the means of the experimental treatments and the control mean and tables are given. For the case of unknown variance or unequal sample sizes conservative upper confidence bounds are suggested.'

+SAFE, a safety extension to the Capability Maturity Model -Integrated (CMMI) has been developed and trialed in Australia, for use in assessing suppliers of safety-related systems. This paper describes the latest version of the safety extension and also reports on the results of seven trials.

No abstract