# Event Definition

Use this text box to specify a definition for the event.

### Definition Syntax:

You must specify an event definition using the following syntax:

Variable Operator Value

where the Variable is a column in the domain specified using the Findings Domain to Analyze parameter, the Operator is used to specify a comparison (see examples below) and the Value is some numeric or character value.

You can combine definitions using Boolean operators such as and or or.

For example, to define a Hypertension event, where the systolic blood pressure is greater than 140 and the diastolic pressure is greater than 90:

| 8 | Type SYSBP >= 140 and DIABP >= 90 in the text box.

You can set multiple conditions for each definition. Enclose these compound definitions in parentheses. For example, if your data have occasional missing values (the symbol for missing values is typically a period (.)) and you would prefer to interpret missing values as meeting event criteria:

| 8 | Type (SYSBP >= 140 or SYSBP =.) and (DIABP >= 90 or DIABP = .) in the text box.

### Operators

Comparison operators (also called binary operators) compare a variable with a value or with another variable. Comparison operators propose a relationship and ask SAS to determine whether that relationship holds. Only observations that meet the condition(s) specified are included in the analysis.

The comparison operators, available to you are shown below.

Symbol | Definition | Example
= or EQ |
| • | equal to
| • | Entering Gene EQ “EGF” subsets the input data set, retaining only those observations where the value in the Gene column is EGF.
^= or NE |
| • | not equal to
| • | Entering IndividualNum ^= 450 subsets the input data set, retaining only those observations where the value in the IndividualNum column is not equal to 450.
< or LT |
| • | less than
| • | Entering Position < 100000 subsets the input data set, retaining only those observations where the position value is less than 100,000.
> or GT |
| • | greater than
| • | Entering Position GT 100000 subsets the input data set, retaining only those observations where the position value is greater than 100,000.
<= or LE |
| • | less than or equal to
| • | Entering Position <= 100000 subsets the input data set, retaining only those observations where the position value is less than or equal to 100,000.
>= or GE |
| • | greater than or equal to
| • | Entering Position GE 100000 subsets the input data set, retaining only those observations where the position value is greater than or equal to 100,000.

### To Specify an Event Definition:

| 8 | Enter the definition in the text box.