Table of Contents
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Overview
Forms (e.g., CRF's, Questionnaires, Instruments) in StudyTRAX are referred to as Variable Groups. The forms define the variables/questions and the layout. The form designer supports nearly all imaginable for layout and design requirements, anything that can be done on the web can be done with StudyTRAX forms.
Feature Summary
- Configurable look/layout of the form
- Leverage JavaScript for programmable logic
- Set up once and use at multiple subject visits
- Easily copy to another study
- Missing Values can be defined
- Perform validation on values
Preparing for Analysis
Think "One" Form
StudyTRAX automatically recodes variables over time in Data Sets. Thus, forms are created ONCE and then assigned to as many encounters (e.g., baseline, week 1, etc.). Then, upon export (statistical package, spreadsheet), variables are automatically recoded.
For instance, a form with one variable called weight collected at baseline, month 1, month 2, etc. The form would only be created once, but assigned to multiple data collection points. The dataset export has two layout options, both automatically handled (see image).
Display Change Does Not Equal New Form
Some items on a form are not collected at different time points. However, this would NOT mean another form as to be created. Instead, the logic would drive what is displayed/hidden. The main issue is to keep on one form all the variables that conceptually go together.
For instance, the form "Lab Results" may have 20 different lab value (e.g., K, white blood cell count, etc.). However, only some of these variables are collected at each study visit. In this case, only those variables collected would be shown as appropriate, but the form would contain ALL the "Lab Results". Sometimes, sections of a forms and associated variables are always either collected or not collected together over time. In such cases, separate form sections will also work.
Handling Small Differences
Sometimes a form is nearly identical at every data collection point, but there is a slight difference in the question for some items. For example, at baseline the prompt is "what's your highest pain rating in the last two weeks?", whereas at follow-up, the prompt is "What's your highest pain rating since the last visit?" Note that the data entry prompt is part of the data definition (i.e., tied together with how the variable is defined , e.g., a number with the prompt "Age:") and each variable only has ONE prompt.
Often with only a slight change in the display prompt the statistician will prefer to keep the variable in the same column within the data set (option 1 below). This is done in study by either creating a second, non-exportable variable, that is only used for the display prompt and is shown/hidden when appropriate. Or the time reference is taken out of the prompt and put in a heading and the heading is shown/hidden when appropriate (e.g., one heading says, "The following question refer to in the past week", whereas the other heading says, "The following questions refer to since the last visit".
Other times, the statistician will prefer a completely new variable (option 2 below). There are pro's and con's as to how to handle such cases, but the general recommendation is to define as few of variables as possible using different display prompts so that everything lines up in the dataset (Option 1).
What to Consider
- Review the meaning of Universal Subject Variables, Project Variables, and Encounter Variables.
- Universal Subject Variables
- Plan the variables that will be Universal Subject Variables. These variables are used across all projects. Subjects enrolled in subsequent projects will not need their universal subject variables re-entered. Individual projects can opt out of viewing any of the Universal Subject Variables.
- Project Variables
- It is recommended to use a discontinuation date in your project. This will keep subjects who are no longer actively participating in the project from showing up on the Subjects Due list and their Subject Overview page will indicate the subject is discontinued
- Encounter Variables
- A variable group that will be collected on multiple occurrences only needs to be created one time. The intervals determine the data collection schedule and the same variable group can be collected on multiple intervals.
- Variables
- When creating a variable, be sure the variable type is correct. The variable type cannot be changed once data is collected. A common error is to use a text type variable instead of a numeric type variable.
A minimum and maximum allowed value can be entered for numeric variables.
Tip Be sure to set up this validation before any data is entered as it can not be set up or tightened after data entry has started
- How can the data burden be minimized?
- Variable defaults
- Calculated variables
- Rather than setting up a text variable consider whether a pick-list can be used with one option being "Other". Selecting other can trigger a text box to display.
- Determine if any numeric or categorical variables need missing values defined
- Think about whether a variable should be not required or required. If required, should a value be mandatory for data entry?
- Variable Groups
- Plan what the form should look like
- Think about the design and layout options that best facilitate data entry
- If subjects will enter data, are there any special needs (e.g. sound, large fonts, etc.)?
- Use the Layout tab's Default Prompt Width and Default Answer Width to accomodate the majority of the variables' widths
- Before copying variables, verify the setup of the variable to be copied is correct to minimize changes
- The *Layout *tab of the Variable Group Update page can be used to customize the form (e.g., colors, layout of questions, adding images)
- Will there be a paper source? If so, will data be double data entered and which variables?
- Be sure to import and leverage existing forms already set up on your system and the StudyTRAX Sharing Forms site
Setup Steps
To add forms (variable groups) to a project:
- From the Project Overview page select the Variable Groups tab in the left panel
- Click the icon to add a new variable group
- Enter the form name on the Attributes tab
- Add the form questions on the Variables tab
More detailed information about each tab on the Variable Group Update page can be found here.
Examples
- Multi-media data entry with video, sounds, pictures, etc.
- Data entry forms with extensive validation routines (e.g. skip logic, etc.)
- Forms that integrate data entry with clicking on an image, or a form with a background image with data entry field positions designed accordingly
- Standard layouts with one variable per row
- Matrix type layout
- Table layouts
- Automatic scoring
See Form Design for ideas on what can be done with forms.