How To Use Expression Questions

## How To Use Expression Questions

### Overview

Expression Questions are hidden questions that execute scripts and optionally store calculated values.

They are commonly used to:

* Perform calculations.
* Classify respondents.
* Store intermediate values for later use.
* Support complex survey logic without displaying a question to the interviewer or respondent.

This article explains how to create and use an Expression Question.

### Step 1: Add an Expression Question

Add an **Expression** question to your survey and enter a descriptive body text.

Although the body text is never displayed during the interview, it serves as documentation to help you identify the purpose of the expression when reviewing the survey or analyzing exported data.

### Step 2: Write the Expression

Open the **Answers** tab of the Expression Question and enter the script that performs the required calculation or logic.

An Expression Question must return a value using a `return` statement.

### Step 3: Use the Returned Value

Once the Expression Question has been evaluated, you can reference its returned value anywhere in your survey using the `Answer()` function.

For example, if the Expression Question has an index of **10**, retrieve its value using:

```javascript
Answer(10);
```

For improved readability and maintainability, it is recommended to reference the question by its **variable name** instead of its numeric index whenever possible.

 

Overview

Expression Questions are hidden questions that execute scripts and optionally store calculated values.

They are commonly used to:

• Perform calculations.

• Classify respondents.

• Store intermediate values for later use.

• Support complex survey logic without displaying a question to the interviewer or respondent.

This article explains how to create and use an Expression Question.

Step 1: Add an Expression Question

Add an Expression question to your survey and enter a descriptive body text.

Although the body text is never displayed during the interview, it serves as documentation to help you identify the purpose of the expression when reviewing the survey or analyzing exported data.

Step 2: Write the Expression

Open the Answers tab of the Expression Question and enter the script that performs the required calculation or logic.

An Expression Question must return a value using a return statement.

Step 3: Use the Returned Value

Once the Expression Question has been evaluated, you can reference its returned value anywhere in your survey using the Answer() function.

For example, if the Expression Question has an index of 10, retrieve its value using:

Answer(10);

For improved readability and maintainability, it is recommended to reference the question by its variable name instead of its numeric index whenever possible.