Computer-Aided Clinical Trial Recruitment Based on Domain-Specific Language Translation: A Case Study of Retinopathy of Prematurity

Figure 2

SDE for authoring CT recruitment criteria. The left panel is a list of data fields that can be used as rule variables in the search patterns. These data fields come from the database schema of the central data repository. The right panel is a graphical rule editor. It supports conditional predicates (composed of rule variables and comparison operators, e.g., [BirthWeight] <= 1.5), logical operators (AND, OR, and NOT), and parentheses (specify precedence). For each rule variable, the available comparison operators are strictly confined based on its data type. If the variable is numeric or date type, allowed comparison operators will be “>=, <=, >, <, =, !=”. If the variable is string type, the allowed comparison operator will be “=,” and the rhs (right-hand side) constant can be a string literal with wild cards (“%”). The sequence of rule components can be adjusted by drag and drop. Furthermore, the graphical editor can generate a rule expression into the textual editor. The textual editor also allows the user to directly edit rule expression with autocomplete (IntelliSense) utilities.