ABSTRACT

Multiple objectives pursued in clinical trials typically exhibit a hierarchical structure; e.g., they can be divided into primary and secondary objectives (for a detailed classification of primary and secondary endpoints, see D’Agostino, 2000). The primary objective is typically formulated in terms of the primary analysis which describes the most important features of the treatment. In most registration trials, the primary analysis determines the overall outcome of the trial, provides the basis for the regulatory claim and is included in the product label. Secondary analyses (including secondary endpoints and subgroup analyses) play a supportive role and provide additional information for prescribing physicians, patients, payers, etc.