Multiple comparisons in long-term toxicity studies.

Several multiple comparison procedures (MCPs) are discussed in relation to the specific formulation of type I and type II errors in toxicity studies and the typical one-way design control versus k treatment/dose groups. Examples for these MCPs are: the standard many-to-one MCP (Dunnett's procedure), sequential rejection modifications, closed testing procedures, many-to-one MCPs with an ordered alternative hypothesis, procedures based on the assumption of a mixing distribution of responders and nonresponders, and MCP's for multiple end points.