The Study Design and Study Forms builder in Castor CDMS allows you to create and customize your electronic Case Report Form (eCRF). Castor CDMS organizes study into four main components: Visits, Repeating Data, Surveys, and Survey Packages.

Visits

• Visits and forms make up the primary Case Report Form (CRF).
• When a participant is created, all the Visits and associated study forms are automatically created for them.
• Visits represent time periods in a study (e.g., "Baseline," "Visit 1").
• They may have specific durations (e.g., 2 months).

The basic structure of your eCRF is determined by Visits, Forms, and Fields:

Forms

• Forms are sections within a visit, designed to group related questions (for example Demographics or Study inclusion).
• Each visit can contain multiple forms to enhance usability and reduce complexity.
• Forms are also used in repeating data and surveys.

Fields

• Fields are the actual questions in your eCRF.
• Each form can contain multiple fields, but it is recommended to keep the number of fields per form manageable to improve user experience.
• Find more about different fields in section Fields and field properties

Fields in the Study forms builder:

Repeating Data

• Repeating data is mostly used for events or measurements that occur multiple times but with an unknown frequency. 
• It follows a one-to-many (1:N) relationship with the participant.
• Example: For one participant, there might be two blood pressure measurements, while for another, there could be six.
• Examples of data stored in repeating data:
  • Adverse events
  • Medications
  • Repeated measurements (e.g., blood pressure).

Find more information on when to use Repeating data in the article: What is the difference between the types of repeating data in EDC/CDMS?

Surveys and Survey packages

• Surveys are questionnaires sent to participants via email or the Castor Connect App.
• Surveys are distributed in survey packages, which group surveys for easier management.

Creating Your Study Structure

To create a basic study structure, you’ll define visits and forms within the Study Design section.

Questions to Consider:

Are the questions answered by a healthcare professional directly in Castor CDMS?

• Use Visits and forms.

Do the questions have a "one-to-many" relationship?

• Use repeating data if the frequency of events or measurements is unknown or if multiple measurements needs to be taken and displayed in the data entry view in a table form.

Are the questions going to be sent via email?

• Use surveys and survey packages or the Castor Connect App.

How should the data be exported?

• Consider various export formats for Visits, Repeating data and Surveys:  Export data formats in CDMS

Example Scenarios

• Visits and Forms: Use for structured, fixed data collection like a "Baseline Visit."
• Repeating Data: Use for unpredictable data, like the number of adverse events per participant.
• Surveys: Use to collect responses directly from participants via email or app.

By asking these questions and structuring your study accordingly, you’ll create an organized and user-friendly eCRF for efficient data collection.