Figure 1.

Specifying selection criteria in the Ad Hoc Query form. This and the next figure deal with patients in a prospective breast cancer study. The selection criteria are patients who had menarche at age 16 years or later, no pregnancies, irregular menses, and a history of either estrogen replacement therapy or oral contraceptive use. This is specified by the compound selection criterion “1 & 2 & 5 & (3 | 4)” in the lower middle of the figure, where the numbers refer to individual selection criteria. The rightmost column in the figure, “Enumerated/Ordinal Values,” is used to display (and manipulate, if necessary) the internal integers corresponding to symbolic phrases for such data types. Thus, the number 2 corresponds to the symbolic phrase “irregular” for the attribute “menses.”