Extensions for multiple treatment groups

If the categorical outcome was Main Reason for Discontinuation which was classified as Adverse Event, Withdrawal of Consent, Protocol Violation, Other, there may be interest in expressing an OR in relation to Adverse Event, in which case we would collapse the other three categories and proceed as in the binary case. 

In this section we will discuss the extension of the t-tests for continuous data and the chi-square tests for binary, categorical and ordinal data to deal with more than two treatment arms. 

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