Calculations or Calculated Variables provide the means to create calculations based on various data elements. Calculations are most commonly used within a Survey to create a new variable based on survey responses such as 'BAC' or 'AUDIT Score'. However, IMPACT Feedback also provides Calculations in Reports, Messages, and Events. Please see the table below for information about each calculation type.


Quick Show Condition
Used for the creation of a variable to use in show logic (item condition). Common uses of the Quick Show Condition are to variables used to hide survey questions (or pages) based on the response to a previous question.

Use this to create a 'Cannabis Logic' item that will hide subsequent questions about Cannabis if the case responds a certain way to a previous question about Cannabis.
Conditional Expression
Use this to return one of two possible outputs (either return 'this' or 'that'). The output variable can be another number, a date, text, True/False or another calculation.

A conditional expression can be used in a report to return the text 'never' for a student's Drinking Days Per Month value instead of '0 days per month' if the student said they have have never drank and entered zero drinks into the two week calendar.
Conditional Bucket

A conditional bucket expression works much like a conditional expression except that in this case the input variable (ie: responses to a survey question) can be broken into various buckets with corresponding output.


A conditional bucket expression can be used to return a risk category based on a Family History Risk Score for use in a report.  Risk scores within a set of defined numerical ranges will return a particular risk category: 0-2 returns a risk category of 'Low', 2-4  returns 'Medium', 4-7 returns 'High' and 7+ returns 'Very High'.

Date Manipulation
Date manipulation adds or subtract from a specified date. 

A date manipulation calculation could calculate the # of days since the case was created/added to the system.
Date Number Extract
These calculations are used to extract a numeric component (hour, day, year, etc.) from an event within IMPACT Feedback.

This can be used to return the day of the week a survey was completed for use in a report.
Formatter
This calculation provides a means for formatting the input variable for display (ie: in a Feedback Report or Message).

The 'precision' function can be used to round BAC to the desired number of decimals or return a date calculation in a specific format (mm/dd/yyyy),
Math Expression
Math expression calculations provide a robust solution for computing complex math equations. 

For example, AUDIT Score is calculated by assigning a certain numeric value to each response on the scale.
Math Function
This calculation type provides the following three options for rounding a numeric value to a whole number. 
  • Round: Rounds to nearest whole number
  • Ceiling: Rounds up to the next whole number (ie: '6.1' becomes '7')
  • Floor: Rounds down to the next whole number (ie: '3.7' becomes '3') 
Normative Lookup
Use this to compute normative information typically displayed above normative charts. Normative lookup calculations reference your Organization's norms in order to provide normative percentage or percentile rank to be inserted into the Feedback Report.