Similar Equipment Groups are collections of manufacturer/model numbers that are closely similar with respect to function, design and specifications.  Similar Equipment Groups can be created, updated or deleted with the Similar Equipment Group Builder, which is accessed by first selecting Similar Equipment Group Analysis from the Analysis Level menu on the Main Screen and then clicking the Similar Equipment Group Builder button.  

If no Similar Equipment Groups currently exist, the first screen that will appear is the Create a New Similar Equipment Group Code screen for entering a Group Code and Description. Clicking the OK button activates the Similar Equipment Group Builder. 
The Create a New Similar Equipment Group Code screen can also be activated by clicking the New Group button on the Similar Equipment Group Builder.  
 
Items are added to a Similar Equipment Group on a model number-by-model number basis. This is done by clicking on a model number in the Candidate Models List and dragging it to the Member Models List. To facilitate group definition, each of these lists may be sorted according to several sort keys. The sort keys for the Member Models list are accessed from the Members menu. The sort keys for the Candidate Models are accessed from the Candidates menu.  Once a Similar Equipment Group is defined, the data from its member models will be grouped for Similar Equipment Analysis from that point on.
 
A model number is removed from a group by clicking the model number in the Member Models list and clicking the Remove Model button. An entire Instrument Group may be deleted by clicking the Delete Group button.
 

During interval analysis, if a group is found to be inhomogeneous, IntervalMAX automatically creates Subgroups or subsets of items in Similar Equipment Groups whose service history data have been tested and found to be homogeneous with respect to the rate at which out-of-tolerances or occur.  The process of creating Subgroups is one in which groupings are created, redefined, recombined, or subdivided until the smallest possible number of homogeneous Subgroups is obtained.  Confidence levels for creating subgroups and recombining them can be entered in the Subgroup Test Confidence Level and Recombine Test Level boxes of the Analysis Parameters Screen.