Defining Hierarchy Levels

You must define at least one hierarchy level for each classification hierarchy. If the hierarchy has more than one level, each level must be logically related so that the topmost level contains the most general values and the bottommost level contains the most specific ones.

You must make the following design decisions for each hierarchy level:

• Set the Allow Classification Flag. If set to Yes, this level can be assigned to object subtypes, which allows objects of that subtype to be classified to values contained in this hierarchy level. (When you define object subtypes, you specify whether the hierarchy level is allowed, not allowed, or required for each particular object subtype; see Assign Hierarchy Levels to Object Subtypes.) The default setting is Yes.

  If set to No, the hierarchy level still exists and serves to organize classification values in the levels below. For example, you might want to create a Project > Study > Site > Patient hierarchy even if you do not generate reports that are specific to a single site. In this case, you can set the Allow Classification Flag to No for the Site level. In the Reports screen, folders for each site are displayed within each Study folder. Each site folder contains a folder for each patient. Any patient-specific reports, such as for a serious adverse event, are contained in a patient's' folder.

• Set Term Uniqueness. This setting determines the way Oracle LSH enforces the uniqueness requirement for classification values in the level. This attribute has these possible settings:
  • Unique Within Level. Each classification value contained in this level must be unique relative to all other classification values in the level.

    For example, there can be only one Site called General Hospital in the Site level. Because each child classification value can have only one parent value, General Hospital can be associated with only one study.

  • Unique Within Parent. Each classification value contained in this level must be unique relative to the other classification values in the level that are related to the same parent classification value.

    In this case, if the site General Hospital is participating in more than one study, the classification value General Hospital can appear multiple times in the Site level, if it is associated with a different study each time (see Figure 5-1).