Frequently Asked Questions (FAQs)


What is MyCap?

MyCap is a mobile device application that can be used by participants to complete surveys and tasks associated with REDCap projects. Available as an external module that can be enabled on a REDCap project, MyCap allows researchers to capture participant / patient-reported outcomes via the MyCap app on a participant’s mobile device. The data is then sent from the app to the REDCap project. It is particularly helpful for researchers who wish to communicate and collect data from participants on a frequent basis.

What happens if I run into a problem collecting data using MyCap outside of normal business hours (e.g., at 2 AM)?

Email your REDCap administrator (enter your institution to find your administrator here) and the MyCap inbox Please describe the problem, include screenshots if possible, and include any errors or warnings you’re seeing.

How is MyCap Different from REDCap Mobile?

MyCap is an application installed on a participant’s mobile device so the participants can complete data collection instruments, surveys, and other tasks remotely and over a period of time.

Alternatively, the REDCap Mobile App is primarily used when an internet connection is unavailable or unstable. The REDCap Mobile App is typically downloaded to the study team’s mobile device and taken to the participants, rather than downloaded to a participant’s device.

Getting Started

How do I get started with MyCap?

  1. Check with your REDCap Administrator (enter your institution to find your administrator here) to see if your institution has enabled the MyCap External Module in REDCap. If not, MyCap is not available for your project.
  2. If MyCap is enabled at your institution, set up a classic/traditional project in REDCap and design your data collection instruments (MyCap is not currently compatible with the longitudinal project REDCap setting. MyCap uses REDCap’s infinitely repeating instruments to store longitudinal data).
  3. Request to enable MyCap on your project.
  4. Use the MyCap interface to set schedules, prompts, and instructions for participants.

Who can create projects compatible with MyCap?

REDCap administrators can create new projects compatible with MyCap. Normal REDCap users cannot setup MyCap without help from an administrator, but this feature is on the roadmap.

Can I enable MyCap on an existing project?

Yes. REDCap administrators can enable the MyCap external module on existing classic REDCap projects. MyCap is not currently compatible with the “longitudinal data collection with defined events” feature. MyCap uses REDCap’s “repeatable instruments” feature to store longitudinal data.

Messaging / Notifications

When do push notifications go out and can I change it?

There are two types of notifications for mobile apps, local notifications and push notifications. A local notification is scheduled by the device and will be seen when a participant is online or offline. A push notification is sent from a server to the device and can only be received when a participant is online. Push notifications sent when a participant is offline will be saved until the participant is online.

MyCap uses local notifications for scheduling tasks. Participants will receive a local notification at 8AM with the message “You have an activity to complete today.” Currently the 8AM notification time cannot be changed, but adding flexibility is very high on our list of priorities. MyCap uses push notification when a researcher sends an ad hoc message to a single participant or an announcement to all participants. These can be sent anytime but they cannot currently be scheduled beforehand.

Can I schedule notifications regarding tasks or overdue tasks?

MyCap currently sends notifications for incomplete tasks at 8 AM. Later in 2021, notifications will be able to be scheduled a variety of ways. For example: remind the participant at 8PM that a task is ready; remind the participant that they forgot to complete a task due yesterday; remind the participant to complete a task at both 8AM and 8PM.

Active Tasks

What is an active task?

Active tasks are designed to measure sensory information. Amongst many other capabilities, active tasks allow researchers to measure a participant’s range of motion, spatial memory, reaction time, speech recognition abilities, and tapping speed all through the MyCap Mobile app. These measurements are taken through participant completion of specific tasks set out by the research team. Active tasks can capture information that would otherwise typically require a clinic visit to capture.

Does MyCap support active tasks?

MyCap supports active tasks in seven distinct categories. This includes activities related to motor skills, fitness, cognition, speech, hearing, hand dexterity, and vision. Click here to see which activities are supported by iOS versus Android platforms.

QR Codes / Participant Activation

What information is in the QR code?

The QR code contains three data elements: the participant ID, REDCap project ID, and an institution ID. Researcher teams can view each participant’s unique QR code in their MyCap online interface on each Participant’s Profile.

Can I automatically generate the QR code to participants?

Yes! We’ve created HMTL that you can use to automatically generate the QR code for participants. You can do this by pasting the HTML into the (a) text that is displayed after a survey is completed or (2) REDCap Alerts and Notifications to automatically email QR codes to participants. Check out our QR Code Quick Guide for instructions on setting up the automated emails.

How do participants join a project after they have downloaded the mobile app?

Participants join your project by using their mobile device to scan a QR code.

To generate a participant’s QR code, first the participant has to have a record in your REDCap project. Participant records can be created by having the participant complete an intake survey (recommended). Alternatively, research teams can add (or import) participants directly in REDCap or directly into MyCap.

Note: if you added your participants to REDCap but are not automatically distributing them through alerts and notifications, you must generate a QR code for each participant from within the MyCap interface, under the participant’s profile.

MyCap is working on additional methods for participants to join projects (e.g., the use of deep links that can be sent via email or text and, once selected, enroll the participant in the project).

How do I send participants their QR codes?

We recommend sending the QR code by email to participants using REDCap’s Alerts and Notifications (read more in our Quick Guide).

The QR code can also be scanned directly from your computer if participants are enrolled in-person/in-clinic.

Alternatively, the QR code can be screenshotted and mailed to participants.

Can I export QR codes in groups or for all participants at once?

Not currently but this is a feature we are considering!

Can MyCap support remote participant setup/enrollment?

Yes, as long as participants have access to two internet-capable devices.

For example, participants can enroll by completing any electronic survey in which they provide the required enrollment information, in addition to a contact email. Next, the QR code can be emailed to the participant. Then, the participant would use their mobile device (Device 1) to scan the QR code that is open another device (Device 2).

Can I allow participants to disable the passcode requirement when they open the app?

A participant is required to create a 6-digit PIN unique to the MyCap app. Participants may also unlock the MyCap app using biometric identification when the device allows it. Participants can choose to disable the app passcode security in MyCap settings.

REDCap Features

Is branching logic supported?

Yes. Single-statement ([foo] = 1) branching logic has always been supported. Complex branching logic ([foo] = 1 AND ([bar] > 2 OR [baz] = ‘Hello’)) is available since MyCap Android v1.5.1 and iOS v2.5.0. However, mathematical functions “([foo] > ROUND(2.5)” are not supported.

Can I use action tags/smart variables? 

MyCap is not compatible with REDCap’s smart variables, piping, field embedding, special functions, and most action tags. MyCap does honor the @HIDDEN action tag and does have a number of unique action tags specific to MyCap. For example, the @MC-FIELD-FILE-IMAGECAPTURE action tag applied to a REDCap File Upload field would allow a participant to capture a photo using their device’s camera. You can see the list of MyCap action tags by visiting: Your REDCap Project > MyCap > Help > Annotations > Extended Behavior. 

Is piping supported?

Not at this time.

Can you put HTML in field labels?

Not at this time. Native mobile application development does not use HTML to render screens. We will convert basic HTML elements, such as links and lists, to the appropriate equivalent in the future.


Could you describe the security features of MyCap?

  • Participant data is stored locally on the device in an AES-256+SHA2 encrypted database. Data remains on the device if an internet connection is not available. Applies to both iOS and Android devices.
  • When an internet connection is available, data is transmitted directly to REDCap using a SSL (TLS v1.2) connection. A hash-based message authentication code (HMAC) is used to verify the integrity of the data and to authenticate the sender.
  • Participant entered data (i.e. task responses) are not stored or sent anywhere else. Data exists on the participant’s device or on your server.
  • Data is wiped from the device after the MyCap app verifies that data has been successfully transmitted. Note that there is an optional MyCap feature that lets a participant see some of the data s/he has entered for an individual task/instrument/survey. By default, data is wiped.
  • Participants create a 6-digit PIN that is used to open the app. A participant can disable the PIN feature.

Also see security.pdf and architecture.png

Does MyCap use any 3rd party services?

The MyCap mobile app uses Firebase Analytics, Crashlytics, and Cloud Messaging. Firebase generates its own identifiers that live on the participant’s device. There is no way for Vanderbilt to link a MyCap participant code to a Firebase user identifier. Participant meta-data stored in Firebase cannot be linked to participants in your project.

Messages sent to and from a participant are transmitted via the MyCap API, not Cloud Messaging. Cloud Messaging simply handles push notifications and the push notification message is always “You have a secure message waiting.”


How do I get help with MyCap?

  • Feature requests or bug reports: Post to the MyCap space.
  • Join the weekly MyCap Assistance call, Tuesdays at 11AM Central
  • Email if you have something private to discuss that should not be posted in the MyCap space. Example, a specific project for one of your investigators.
  • REDCapU webinar #7. ~2hr overview of MyCap. For REDCap Admins
  • Instructional video. Excerpt from webinar #7. For REDCap Users. I typically direct new users here to answer basic questions.