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Using REDCap for Registries

In this section, we will use a sample registry with fictitious data to highlight some of the benefits of using REDCap for your registry. Our sample registry is a recruitment registry, used for identifying and contacting potential participants for active studies in our department.
  • Forms

    REDCap uses data collection instruments called ‘forms’ as containers to structure data; each item on a form is a field. Think of a form as a data collection tool used to capture data elements. Typically, researchers divide forms by some domain, such as Demographics and Labs, or by work tasks like Clinic Intake and Contact Follow-Up.

    In our sample registry, we create three forms: Demographics, Labs, and Study Management, each form has user-defined fields related to data for that form. The outline of what we want our registry to collect is as follows:

    • Demographics: First Name; Last Name; Gender; Birth Date; Phone; Email
    • Study Management: Opt-Out; Enrolled in a Study; Last Contact Date
    • Labs: A1C result; A1C Date; Hemoglobin A1C; Hemoglobin A1C Date
    • Example: Demographics

      Example: Demographics

      Let us quickly review each field in the Demographics form (see Figure 1).


      Figure 1: Demographics Form

      • Record ID – REDCap automatically assigns a unique record identifier when you create a new record. This aids with keeping all the records straight and minimizes duplication. This option can be disabled in case the study had its own identifier it wanted to use. This is the only field REDCap auto-creates and it exists on all forms.
      • First NameText Box – The first name of the subject, plain and simple without any validation.
      • Last NameText Box – The last name of the subject. Again, no validation.
      • GenderMultiple ChoiceDrop-down List – The subject’s gender. Built in validation to limit to only items in the list.
      • Date of BirthText Box – The subject’s birth date. This field is using Date (M-D-Y) validation. Note REDCap only supports three of the most common date formats: M-D-Y, D-M-Y, and Y-M-D.
      • Phone NumberText Box – The subject’s phone number. This field uses the Phone Number validation.
      • E-MailText Box – The subject’s e-mail address. This field uses the e-mail validation feature.

      Who is Who: Record Identifiers in REDCap

      Remember REDCap automatically assigns a unique record identifier when you create a new record. The Record ID belongs to the participant, so all forms for a participant will have the same Record ID. The figure 2 below shows this relation:


      Figure 2: All forms for a participant have the same Record ID

    • Example: Study Management

      Example: Study Management

      The ‘Study Management’ form (Figure 3) is used for registry management. Consider it a working form for coordinators or registry managers to track statuses for the participants in the registry. In this form, we have four fields.

      • Record ID – Again, REDCap automatically assigns the unique identifier to the form.
      • Opt Out? – Yes-No –This field is used to identify if a participant has opted out of the registry. The default value is set to ‘No’. In addition, this field is required to have a value as indicated by the “*must provide value” text.
      • Enrolled in Study – Check Boxes (Multiple Answers)– This is a multiple answer field that allows the assignment of study or studies in which the participant is enrolled.
      • Last Contacted Date – Text Box– The date the participant was last contacted. This field is using Date (M-D-Y) validation.
      study management

      Figure 3: Study Management Form

      Field Validation

      REDCap supports of variety of data validation and quality assurance features (see Data Collection Tool Design for guidance on using such features).

    • Example: Labs Form

      Example: Labs Form

      Let us review each item in figure 4, the Labs form:

      • Record ID – Ahh! Record ID once more in order to associate the forms with the participant.
      • Blood GlucoseText Box – The value of the Blood Glucose test result. Includes validation for numeric values 0-999.
      • Blood Glucose DateText Box – The Blood Glucose test result date. This field is using Date (M-D-Y) validation.
      • Hemoglobin A1CText Box – The value of the Blood Glucose test result. Includes validation for numeric values 0-999.
      • Hemoglobin A1C DateText Box – The Blood Glucose test result date. This field is using Date (M-D-Y) validation.

      Figure 4: Lab Form

      Field Notes

      REDCap allows the user to define Field Notes for fields which is small reminder text displayed underneath the field. In this example, we add a field note if the desired unit ‘mg/dL’ to the Blood Glucose field and the ‘%’ unit to the Hemoglobin A1C field. This helps supports consistent data entry.

    • Repeating Fields and Forms

      Repeating Fields and Forms

      At this point, you may be asking, “What should I do if I have to collect multiple labs over time?” Repeating Forms is a feature that allows individual ‘instances’ of the same form. Labs commonly have multiple values, and using repeating forms is an easy, organized way to collect those values. Figure 5 shows we have seven instances of Labs for the Record.

      When should I use Repeating Fields or Repeating Forms?

      If you need to collect data in a repeated manner, you can enumerate fields on a form (e.g., Contact_Date_1, Contact Date_2, and Contact_Date_3) or repeating forms (see Figure 5).

      Repeating fields work best if you know exactly how many iterations of a field you will have and that it will not change. Otherwise, it is best to use Repeating Forms.

      redcap repeating instruments

      Figure 5: REDCap Repeating Instruments

  • Managing Records

    REDCap offers a few features to allow your team to record and track the status of forms.

    • Selecting Form Status

      The “Form Status Complete?” field exists on every form. It acts as a status indicator for the form and has the following three options:

      • Incomplete – Denotes that data entry for the form is not finished.
      • Unverified – Denotes that data has been entered, but not validated, verified, or checked.
      • Complete – Denotes that all data entry for this form is complete and verified.

      Note: Form Status Complete? is an optional form element and is not required for data entry or collection. It is best practice to utilize as it aides with reporting and record keeping.

      form status

      Figure 6: Form Status

    • Locking Records

      The “Lock this record for this form?” checkbox enables a technical constraint in REDCap that protects the form from being modified or deleted. Additionally, REDCap creates audit log entries for locking and unlocking of the forms. Reports may be generated to identify unauthorized modifications or deletions.

      locking records

      Figure 7: Record Lock

    • Deleting Form Data

      Each form has a “Delete Data for THIS FORM only” button, which does just that. It, irreversibly, deletes the current form.

      deleting data

      Figure 8: Delete Record

    • Viewing Record Status

      Viewing Record Status

      REDCap views records as shown in Record ID 3 and 9 (see Figure 9). Each of these records is distinct, with its own forms that store data. The Data Collection Instrument column displays the name of the form, while the “Status” column displays icons, with a green circle indicating a completed form, a red circle an incomplete form, and a stacked circles icon for repeating forms.

      records in redcap

      Figure 9: Records in REDCap

  • Functions

    In addition to forms, there are several functions of REDCap to help you get your research registry off to a great start. For each function we will show how the function could be used to support our sample registry.

    • Surveys

      One of the more common functions REDCap offers is the generation of surveys. Surveys are versions of forms that permit data collection via email, web links, or even paper. Any form could become a survey, although some forms make more sense than others do, for example, a survey could be used to collect demographics for participants, whereas a study management survey is less practical.

      Let’s look at an example.

      For our registry, we want to add a form that records diabetes management methods. A simple question set will be used to determine which methods a participant uses. The first step is to create the data collection instrument (i.e., the form), as seen in Figure 10.


      Figure 10: Diabetes Management Methods Form

      Then we can convert it to a Survey using REDCap (Watch REDCap Survey Video) as see in Figure 11. Surveys can be accessed using a web link and included in email, or a registry web site for data collection. They can even be printed out and abstracted into REDCap later.

      diabetes management

      Figure 11: Diabetes Management Survey

      You will notice that this survey looks different than the form, because the survey uses ‘branching logic’, which displays questions based off the answers to previous questions. In this example, we want to ask about Diet, Exercise, and Medication methods only if they say they use those methods to manage their diabetes. Therefore, once those options are selected, other options appear, as illustrated in Figure 11.

      long survey

      Figure 12. Diabetes Management Survey, expanded

    • Piping

      Piping allows you to use the value of any form in that record in a field or value of another form. In Figure 13, you will see that the survey addresses ‘Sophia SMITH’ in the survey instructions. This is an example of using a REDCap feature called ‘piping’. In this example, we piped [first_name] [last_name] into the survey instructions. This pulls the values of first_name and last_name from the Demographics form and inserts them where desired.


      Figure 13: Piping in REDCap

    • Electronic Health Record Integration

      REDCap supports integration with electronic health records and other data repositories using Dynamic Data Pull and custom APIs. All integration should be completed in collaboration with the REDCap team.

      If you plan to integrate your REDCap Registry and an EHR then its best to use the same coding and options as your EHR. For example, most EHRs capture gender as a multiple-choice field so you would want to capture gender as a multiple choice item in your form.

    • Secure Communication

      Communication is a key component to any successful registry whether between the registry team and the participants or internal communication among the registry team.

      REDCap includes tools to communicate securely and safely with participants, members of the research team, and other collaborators. Using ‘Send-It’, you can upload and send files, including existing project documents, that are too large for email attachments or that contain sensitive data to multiple recipients.

      REDCap Messenger is a chat-based tool integrated right into the project web interface that allows quick communication in a secure environment.

    • Offline Data Collection

      All REDCap surveys and data collection instruments can be downloaded as PDFs and printed for manual offline data collection. Additionally, REDCap offers a mobile application accessible via a smartphone or tablet that permits offline data collection for scenarios where reliable internet service is not available. The mobile app securely stores the information on the mobile device; once internet service is available, the information can be uploaded to the research project.

    • REDCap Reports and Output

      REDCap makes reporting and analyzing records easy with built in tools. For example, we can quickly plot out all Blood Glucose levels for all participants.

      This allows for quick identification of target subjects, outliers, or potential erroneous data. Additionally, ad hoc reporting allows REDCap users to create a host of reports based off any elements in the registry. This permits for easier participant tracking, workflow processes, and error identification.

    • Exporting

      Okay, you have collected quality data and ready to do something else with it. How do you get all that data out? REDCap make it easy with built in tools and formats allows exporting data for analysis a cinch. REDCap allows you can format and de-identify data for analysis in other systems. Storage of all personally identifiable data and protected health information should follow your IRB and institutional protocol.

      Take the next step in REDCap: Advanced Features

      While this section highlights several functions of REDCap that can be used to support research registries, this guide is not comprehensive and there are many other features that may be beneficial for your registry, such as:

      • Auto-validation – allows fields to be verified by trusted biomedical ontologies.
      • Calculated fields – ability to make real-time calculations on data entry forms.
      • Branching/skip logic – permits varying questions dependent on previous answers.
      • Data Quality Tools – allows you to execute rules upon your registry data to check for discrepancies in your data.