JDash – JTrack Dashboard

JDash is a Django-based web platform for managing digital health studies conducted through JTrack mobile applications. This provides a unified interface to design, monitor, and manage behavioral and sensor-based research studies initiated by clinical institutions and the Biomarker Development Group. The system connects mobile app data with researcher-controlled dashboards. The main goal is to simplify the lifecycle of digital studies — from study setup and survey design to subject enrollment, progress monitoring, and data quality.

System Architecture

JDash follows a modular Django-based architecture with a Bootstrap-powered frontend and embedded Plotly-Dash dashboards for visualizing participant compliance, sensor activity, and study progress.

Core Components

• Backend: Django-based application handling authentication, routing, form processing, database operations, and server-side rendering.

• Frontend: HTML templates styled with Bootstrap, using BootstrapTables and AJAX for interactive tables, filtering, file uploads, and dynamic UI updates.

• Database: MariaDB stores studies, subjects, sensor settings, EMA surveys, tasks, audit checks, notifications, and user-related configuration.

• Visualization Components: Interactive compliance visualizations are implemented using Dash and Plotly components integrated within Django views and templates.

• Deployment: Supports local development with Django runserver and production deployment using Apache with mod_wsgi.

Login

Provides authentication for registered users such as investigators and administrators. Users log in with a username and password. A default demo user (demouser) is available for testing.

• Quick access:

  • (1) – Login form

  • (2) – Mail us

  • (3) – Data Deletion form

  • (4) – Language

Login Form

• Visit https://jdash.inm7.de

• Enter your personal credentials into the login fields and press “Login”.

• You can find your login credentials inside a PDF-file that was sent to you via email.

Data Deletion Form

The page allows participants to request permanent removal of their collected data from the JTrack system.

To submit a request, users must provide:

• Subject ID — the identifier shown in the JTrack app

• Email — for confirmation or follow-up

• Reason — an explanation for the deletion request

After submitting the form, the request is forwarded to the study team for manual verification and processing. Data deletion begins once the request is reviewed and approved.

Language Switcher

To change the language of the website please click on the respective flag. Currently only German and English are supported.

Important

The data will be permanently removed and cannot be restored. Please make sure to provide the correct Subject ID.

Direct Contacts

For collaboration enquiries and scientific questions you can contact Dr. Juergen Dukart or Dr. Mehran Turna. For technical questions please contact Jona M. Fischer or Mamaka Narava

Dashboard Tabs

Studies

Central hub for study management, showing all studies the user can access or create. Grid/List Toggle: Allows switching between study card and list layouts. Search Bar: Filters displayed studies.

• Interface Overview:

  • (1) – Create new study

  • (2) – View study details

  • (3) – Edit study

  • (4) – Test and audit logs

Create New Study

The New Study form is used to configure and start a new data collection project in JDash. Here you define basic metadata, sensor configuration, optional EMA surveys, and experimental tasks.

Form Fields

Study name

Unique identifier for the study. Do not use spaces or special characters (prefer MyStudy_01 instead of My Study 01).

Test study

Checkbox indicating whether this is a test/pilot study.

• Enabled: data are clearly marked as test data and can be discarded later.

• Disabled: study is treated as a regular production study.

Study description

Free-text description of the study purpose, protocol, cohort, or any notes for administrators. This is not shown to participants.

Duration

Length of the study in days. Defines the time window during which study is active for each participant.

Number of subjects

Planned number of participants for this study. Used for planning and monitoring recruitment progress.

Recording frequency

Sampling rate for sensor data collection, expressed in Hertz (Hz). This defines how many measurements are recorded per second.

Note

Higher frequencies provide more detailed sensor data but may increase battery consumption and storage requirements. Choose a value appropriate for your study’s goals and device performance limits.

EMA (Ecological Momentary Assessment)

Checkbox to enable or disable EMA for this study.

• Enabled: the study is linked to EMA survey.

• Disabled: no EMA questionnaires are used; only sensor data and tasks apply.

  • Survey title

    Dropdown to select an existing EMA survey that has been defined in the Create Survey section. This determines which questionnaire is delivered to participants.

  • OR UPLOAD EMA JSON FILE

    Drag-and-drop area or file picker to upload a survey JSON directly for this study. - Can be used instead of selecting an existing survey. - The JSON structure must follow the JDash/JTrack EMA schema.

  • UPLOAD EMA IMAGES ZIP FILE

    Drag-and-drop area or file picker to upload a ZIP archive containing image assets used in EMA questions (e.g., visual prompts). - Filenames in the ZIP must match the Image Url fields used in survey questions.

Sensor configuration

How to configure active labeling

In JDash, study conductors can configure the Active Labeling feature to collect labeled sensor data for specific tasks or activities. This setup is essential when precise associations between sensor signals and user-performed tasks are required.

Within the study settings on JDash, you can:

• ✅ Enable active labeling for your study.

• 🎯 Select the sensors that should be recorded during active labeling sessions (e.g., accelerometer, gyroscope, microphone, etc.).

• 📝 Define multiple labeling tasks:

  • Each task has a

    • name (e.g., Walking, Brushing Teeth),

    • preparation time (in seconds),

    • duration (in seconds).

    • description/instructions optional for participants.

  • These tasks will appear in the participant’s app as selectable activities during active labeling.

Note

Active labeling will only be enabled if active sensors are selected in the configuration.

Example task list JSON:

[
  {
    "task_name": "Brushing Teeth",
    "task_duration": 30,
    "task_description": "Please simulate brushing your teeth for 30 seconds."
  },
  {
    "task_name": "Walking",
    "task_duration": 60,
    "task_description": "Walk normally in a straight line for one minute."
  }
]

This list is presented to participants inside the JTrack Social app with autocomplete, so tasks are standardized and consistent.

Tip

Use descriptive task names and clear instructions to help participants understand what to do during each session.

Inside of JTrack Social, Active Labeling is then accessible from the Main view (both in iOS and Android).

Wearable Devices

This section allows administrators to configure external devices (e.g., smartwatches) and define which sensors should be collected as part of the study.

This feature enables integration of wearable sensor data alongside mobile and EMA data.

Enable Wearables

• Show wearables toggle Enables or disables wearable device configuration for the study.

• Add wearable device Button to add a new wearable device configuration.

Device Configuration

Each wearable device includes the following:

Device name

Name of the wearable device (e.g., garmin (vivoactive 6)).

Sensors for this device

List of available sensors supported by the device, such as:

• steps

• spo2

• skin_temperature

• bbi / enhanced_bbi

• ppg

• accelerometer

Select one or more sensors and click Add to include them in the study.

Selected Sensors Table

After adding sensors, they appear in the configuration table with the following fields:

• Sensor Name of the selected sensor (e.g., heart_rate, respiration).

• Sampling rate Frequency at which data is recorded (e.g., 1 min, 15 min).

• Unit Measurement unit for the sensor data (e.g., bpm, breaths/min, boolean, count).

• Remove (×) Deletes the sensor from the configuration.

Note

Adding high-frequency wearable sensors may increase data volume and impact storage and processing performance. Choose sensors and sampling rates based on the study objectives.

Study Details

Overview panel

The panel (1) provides a quick snapshot of the study configuration. It summarizes the most relevant study parameters so administrators can review key settings at a glance.

The panel displays:

• Duration — total length of the study in days

• Sensors — list of passive and active sensors enabled for the study

• EMA — indicator showing whether an EMA survey is assigned (with a Survey details button to view the full questionnaire)

This section helps users verify that the study has been configured correctly before adding participants or exporting data.

Toolbar Panel

The toolbar (2) contains shortcut actions for managing study-level operations. These icons are located in the top-right corner of the Study Details page.

The available actions typically include:

• Refresh — to update the data and view the current status of subjects/sensors

• Export PDF — generates a PDFs of QR codes of participant sheets that have not been used

• Download Data — triggers email to downlaod the collected sensor or EMA data

• Database Actions — to delete subject data from the study and server (e.g., remove all data associated with the study)

These tools provide quick access to the most common administrative actions, allowing study investigators to monitor progress, retrieve data, and perform maintenance efficiently.

Subject Table

The table (1) displays all subjects associated with the selected study. It provides an overview of each participant’s status, app type, sensor configuration, and study duration.

The table includes the following columns:

• Subject ID — the unique identifier assigned to each participant

• App — indicates whether the entry belongs to the main app or the EMA app

• Duration — number of days the participant has been in the study

• Sensor Information — list of sensors enabled for that subject (e.g., at = activity, au = application usage, lo = location)

• Status — participant’s current state (e.g., In study, Left study)

Each subject may appear multiple times if both main and EMA configurations exist for the same participant ID.

Filters above the table allow administrators to search by ID, filter by app type, or filter by sensor usage. This panel is useful for monitoring study progress, reviewing sensor connectivity, and identifying participants who have left the study.

Subject Management Panel

The panel (2) allows administrators to add or remove subjects from the study.

Subject Information

Displays high-level subject counts:

• Total Number of Subjects — planned target number

• Number of enrolled subjects — participants currently created in the system

Create Subject The section allows administrators to generate new subject IDs for the study. To add subjects enter the number of new subjects you want to create in the field Number of Subjects and click Create.

Note

The system automatically generates new subject QR codes following the study’s naming convention (e.g., Demo_Study_00005) which can downloaded from Export PDF toolbar panel.

Remove User

This section allows administrators to remove a subject entry from the study.

To remove a subject, select the subject from the list and confirm the removal.

Important

Removing a subject deletes it from the active study dashboard but does not remove historical data unless server-side deletion procedures are used.

Notification

The notification panel allows administrators to send custom push notifications to selected study participants. This can be used for reminders, announcements, troubleshooting instructions, or follow-up messages.

The panel contains the following fields:

• Message title A short title or subject line that appears in the participant’s device notification.

• Message text The main body of the notification. This can include instructions, reminders, or any relevant message content.

• Recipients list This box displays the subject IDs that will receive the notification. Administrators can manually enter IDs or automatically populate the list using the buttons below.

Two shortcut buttons are provided:

• All IDs — fills the list with all enrolled subjects in the study

• Missing IDs — fills the list with subjects who have not yet submitted recent data or have missing entries, depending on system configuration

After preparing the message and selecting recipients, click Send notification to deliver the message to the participants’ devices.

Important

Notifications are sent via the JTrack backend and delivered through the device’s native notification system. Delivery times may vary depending on network connectivity and device settings.

Close study

This section allows investigators to formally end a study. Once a study is closed, no new data will be accepted from enrolled participants.

Important

Closing a study does not delete existing data. All sensor and EMA data remain available in the server for export and analysis. However, once a study is closed, it will no longer be visible in the dashboard, and no further data collection will occur.

Edit Study

The Edit Study page allows investigators to modify an existing study’s configuration, update sensor settings, change the assigned EMA survey, or adjust task settings. This interface is identical to the New Study form, but the fields are pre-filled with the study’s current values.

The following elements can be updated directly:

• Number of subjects To add more participants check Create Subject section

• Duration

• Recording frequency

• Study description

• Passive sensors and active sensors (multi-select lists)

• EMA settings (change the survey from list of surveys created, images ZIP upload)

• Task list (add, modify, or remove tasks)

All changes are immediately applied once you save the study.

Note

The study name is fixed once the study is created and cannot be changed. It serves as the unique identifier for the study.

Audit / Quality Control

The Test checklist provides a structured way for investigators and research teams to verify that a study is functioning as intended before and during deployment. Each row represents a predefined test case that can be checked directly within the dashboard.

This tool helps ensure data integrity, validate sensor activity, and confirm that participant workflows behave correctly.

The checklist displays the following information for each test case:

• Admin Checkbox used by administrators to mark whether the test case is required or has been reviewed at an admin level.

• Owner Checkbox indicating responsibility or completion for the test case by the assigned user or study owner.

• Description A brief summary of what the test case is verifying (e.g., real-time monitoring, data export, participant enrollment).

• Steps A detailed sequence of actions required to perform the test. These may include navigation steps in JDash, using the JTrack app, scanning QR codes, or validating exported results.

• Expected Outcome Describes what should occur if the test is successful. This provides a reference for determining whether the system is behaving correctly.

• Comments

  Comments allows users to add notes for each test case. Comments can be used to document observations, issues, or follow-up actions during the test and audit process. When a comment is submitted:

  • The comment is saved with the related test case.

  • The username and timestamp are recorded.

  • An email notification is sent to the administrator.

  This allows the study team to track audit feedback directly from the dashboard and ensures that important issues are communicated to the admin promptly.

Note

Test case results do not affect participant data collection. The checklist is an internal quality-assurance tool used only for validation and study monitoring purposes.

Survey

Manages EMA (Ecological Momentary Assessment) questionnaires linked to studies. Displays existing surveys with title, study association, creation date, and actions (edit, copy, delete). Upload Section: Allows importing survey definitions via JSON files.

• Interface Overview:

  • (1) – Create Survey

  • (2) – Upload Survey Json

  • (3) – Edit/View Survey

Create Survey

The Survey module allows administrators to define and manage EMA (Ecological Momentary Assessment) questionnaires that will be delivered to study participants. Each survey contains a title, description, scrolling behaviour, and associated question items uploaded later as a JSON file.

The New Survey dialog provides a guided form for creating a survey entry in the system.

Form Fields

Title

The display name of the survey. This name appears in the survey list and throughout the dashboard.

Description

A short explanation of the survey’s purpose, context, or intended use. This helps administrators distinguish between multiple surveys.

Scroll type

Defines how participants will navigate through the survey items within the JTrack EMA app. Two options are available:

• Horizontal – Questions scroll left/right. Suitable for one-question-per-screen layouts, swipe-based navigation, and compact mobile interfaces.

• Vertical – Questions scroll top/bottom. Suitable for longer pages, forms with multiple inputs, or free-text responses requiring more space.

Select the option that best matches the design of your survey JSON file.

Upload Survey via JSON

Instead of creating a survey manually through the dialog, you can create a new survey by uploading a JSON definition file. The JSON file must follow the JDash/JTrack EMA survey schema.

The JSON must:

• Be valid UTF-8 encoded JSON.

• Follow the JDash survey schema (field names and structure).

• Define at least the survey metadata and a list of items/questions.

Sample JSON format

A sample format file is provided (for example: sample_survey.json). Use this as a template when creating new surveys:

{
  "title": "EMA Pilot validation survey",
  "description": "Short description of the survey purpose and context.",
  "scroll_type": "H",   // or "V"
  "topN": -1
  "questions": [
    {
      "id": "1",
      "active": 1,
      "title": "How are you feeling right now?",
      "subText": "How did you sleep last night?",
      "frequency": 1,
      "clockTime": 0,
      "clockTime_start": "480",
      "clockTime_end": "1430",
      "nextDayToAnswer": 0,
      "category": 1,
      "imageURL": "",
      "url": "",
      "questionType": 3,
      "deactivateOnAnswer": "",
      "deactivateOnDate": 0,
      "activate_question": "",
      "deActivate_question": "",
      "activation_condition": "",
      "deActivation_condition": "",
      "answer": [
             {
                 "id": 1,
                 "text": "",
                 "subText": "",
                 "value": 0.1,
                 "defaultValue": 5.0,
                 "stepSize": 1.0,
                 "minVal": 0.0,
                 "maxVal": 10.0,
                 "minText": "Schlecht | Bad",
                 "maxText": "Gut | Good"
             }
         ]
    }
    // additional items ...
  ]
}

When preparing a new survey, copy the provided sample JSON file and adapt:

• title and description to your study.

• scroll_type to match the intended navigation style.

• The questions list to include all questions, response options, and any additional fields required by the schema.

Important

Only JSON files following this structure will be accepted and correctly rendered by the JTrack EMA app.

Survey Details View

After creating or uploading a survey, selecting it from the Survey list opens the Survey Details page. This page displays all questions defined for the survey and provides tools for managing categories, adding new questions, and exporting the survey as JSON.

Overview of the Question List

The table shows all survey questions in a structured format. Each row represents a single question and includes:

• id — The internal question identifier (order in the survey).

• title — The primary question text (German example shown).

• subText — The secondary text .

• questionType — Input type (e.g., Free Number, Single Choice, Multiple Choice).

• category — Category assigned to the question (e.g., IHG, GH).

• frequency — How often the question is shown in days.

• clockTimeStart / clockTimeEnd — Valid times to receive reminder notification to answer the question.

• nextDayToAnswer — day when the questions becomes available to answer.

This view allows users to quickly review the full content of the survey and to edit or organize items as needed.

Categories Management

The Categories button opens the category management dialog. Categories help group questions into logical sections and are required for surveys with thematic organization (e.g., “Mobility”, “Digital Use”). Investigators can:

• Create new categories

• Rename existing categories

• Delete categories

Adding New Questions

Click New Question to add a new item to the survey. This opens the question editor, where you can define all properties of the question (text, type, category, scheduling rules, etc.).

For a full description of all editable fields, check Create /Edit Question

Once the question is saved:

• It appears immediately in the question list

• It can be edited, duplicated, or deleted through the action buttons on the right

This workflow ensures that new survey items follow the same structure and validation rules as existing ones.

Downloading the survey JSON

The download icon (⬇) in the top-right corner of the page exports the entire survey definition as a JSON file. This JSON can be used for:

• Backups

• Versioning

• Editing offline

• Sharing surveys between studies

Row Actions (per item)

Each question row includes three action buttons:

✏️ Edit

Opens the question editing dialog. Allows modification of text, category, type, time window, and all properties.

📄 Copy / Duplicate

Creates a new question using the selected item as a template. Useful when building surveys with repeated or similar formats.

🗑️ Delete

Removes the question from the survey. A confirmation prompt prevents accidental deletion.

Create / Edit Question

The Question Editor allows investigators to define or modify a single survey question within the EMA survey. Each field controls a specific aspect of how the question behaves, how it appears to the user, and when it is shown.

Form Fields

Below are the descriptions of all fields available in the Create/Edit Question form.

Sequence Id

The position of the question in the survey. Questions are displayed in ascending order based on this value.

Type

Specifies the question type (e.g., Free Number, Single Choice, Multiple Choice, Free Text, Slider). The selected type determines how the question is rendered in the participant application.

Title

The main question text shown to participants (e.g., in German or the primary study language).

Description

Additional descriptive text, explanation, or translation shown below the main question. Useful for bilingual surveys or questions needing clarification.

Use default values toggle

When disabled, all values must be filled manually. If enabled, system-defined default values are used for:

• Frequency

• NextDayToAnswer

• ClockTimeStart

• ClockTimeEnd

• DeactivateOnDate

Category

A numeric category label used to group questions into thematic clusters.

Example:

• 1 - Mobility

• 2 - Digital Activity

• 3 - Sleep

• 4 - Mood

Frequency

Defines how often the question is shown.

Values:

• 0 — Ask at any time the user opens the survey

• 1 — Ask every day

• n — Ask every n days (e.g., 2 = every second day)

NextDayToAnswer

Controls on which study day this question first becomes available.

Examples:

• 0 — Starts on day 0

• 1 — Starts on day 1

• 5 — Question begins appearing on day 5

DeactivateOnAnswer

If set, the question will be skipped or hidden in future survey sessions after a specific answer value is selected. Commonly used to disable follow-up items after a “No” response.

DeactivateOnDate

Defines a study day after which the question should no longer be shown.

Example:

• 0 — No deactivation by date

• 10 — Question disappears after day 10 of the study

Activation time(s)

The time (in minutes from midnight) when the question becomes active.

Examples:

• 480 = 08:00

• 900 = 15:00

If multiple times are provided (comma-separated), the user will receive multiple activations.

These times determine when notifications are sent and when the question appears in the JTrack app.

Deactivation time(s)

The time (in minutes since midnight) when the question becomes inactive.

Must match the number of entries in ClockTime Start if multiple values are used.

Example:

• 1430 = 23:50

• 480,900 must have a matching 600,1000 (start/end pairs)

This ensures each activation window has a corresponding end time.

Note

Activation and deactivation times together define the valid response window for each question. Ensure that end times are logically after start times to avoid invalid configurations.

Conditional Logic

You can define conditional logic for a question to dynamically activate or deactivate other questions based on a participant’s response.

Overview

Each question provides the following fields:

• Activate Question – Sequence IDs of questions to activate.

• Deactivate Question – Sequence IDs of questions to deactivate.

• Activation Condition – Displayed when Activate Question is configured.

• Deactivation Condition – Displayed when Deactivate Question is configured.

These fields allow you to control which questions appear next, enabling branching logic within a survey.

Activate Question

A comma-separated list of question Sequence IDs that should be activated when the specified condition is met.

Example

• 1

• 2,3

This is typically used to display follow-up questions that are only relevant for certain answers.

Deactivate Question

A comma-separated list of question Sequence IDs that should be deactivated when the specified condition is met.

This is useful for skipping irrelevant or mutually exclusive questions.

Conditions

The Activation Condition and Deactivation Condition fields determine when the corresponding branching rules are applied.

• Activation Condition controls when questions listed in Activate Question become visible.

• Deactivation Condition controls when questions listed in Deactivate Question are hidden or skipped.

• These fields become available automatically after entering values in the corresponding Activate Question or Deactivate Question fields.

• Conditions must match one or more answer choices defined for the current question.

Note

Conditions are evaluated against the participant’s response to the current question. The selected condition value must correspond to one of the configured answer options.

Important

For Single Choice and Multiple Choice questions, activation and deactivation conditions can be selected directly from the available answer choices.

For all other question types, condition values must be entered manually. These values are compared against the participant’s response to determine whether the corresponding activation or deactivation rule is applied.

Combined Logic

Both activation and deactivation rules can be configured for the same question.

In the example above:

• Question 13 is activated when the participant selects Ja.

• Question 14 is deactivated when the participant selects Nein.

This allows complex survey flows to be created without requiring separate question groups.

Example scenario

Consider the question:

“Do you currently drive to work?”

Available answers:

• Ja

• Nein

Configuration:

• Activate Question: 13

• Activation Condition: Ja

• Deactivate Question: 14

• Deactivation Condition: Nein

Result:

• Selecting Ja activates question 13.

• Selecting Nein deactivates question 14.

Tip

Use activation and deactivation logic to build conditional survey paths, reduce unnecessary questions, and improve the participant experience.

Image URL

An optional image filename associated with the question (e.g., image1.png). This image must exist in the app’s configured image directory.

URL

An optional external link related to the question (e.g., informational page, instructions, consent wording). The link appears below the question text in the app.

Create / Edit Answer

For question types that require predefined answer options (such as Single Choice, Multiple Choice), the Question Editor displays an Answer Form section. This section allows the investigators to define the selectable choices shown to participants.

Click Add Choice to insert a new answer option row. Each row contains two fields:

Sequence Id

The display order of the option. Choices appear in ascending order based on this value.

Choice

The text label shown to the participant (e.g., Yes, No, Often, Rarely, etc.).

Example:

• 1 → Less than 10 minutes

• 2 → 10–30 minutes

• 3 → More than 30 minutes

Deleting a choice

To remove an answer option, click the trash icon (🗑️) on the right side of the row. The option is removed immediately from the form.

Compliance Monitoring

The Compliance Monitoring tab provides interactive visualizations for monitoring sensor data collection throughout a study. It helps researchers identify missing recordings, inactive participants, irregular sensor activity, and overall data completeness.

The dashboard focuses on subject-level monitoring and allows users to explore recording patterns across study days using an interactive heatmap.

Selection Panel

The left-side control panel allows users to configure the displayed visualization.

Choose Study

Select the study for which compliance information should be displayed.

Select Sensor

Choose the sensor type to visualize (e.g., activity, location, accelerometer, application usage).

Choose X-axis

Select how data should be displayed along the horizontal axis. Available options may include:

• Study day

• Calendar date

Filter Subjects

Optionally restrict the visualization to specific participants instead of displaying the entire study cohort.

Visualization Panel

The main panel displays a heatmap representing sensor activity across participants and study days.

Subject QC Timeline

The Subject QC Timeline heatmap provides an overview of sensor recordings for each participant throughout the study.

• Y-axis — Subject IDs

• X-axis — Study day or selected time axis

• Color intensity — amount of recorded sensor data for the selected sensor

Higher color intensity indicates greater recording activity, while lighter regions may indicate reduced or missing data.

The visualization can help identify:

• Missing recordings

• Participants with limited sensor activity

• Periods of device inactivity

• Sensor interruptions

• Longitudinal recording patterns

Note

Depending on synchronization schedules and backend processing, uploaded data may appear in the dashboard with a delay after the participant syncs the device.

Notification Scheduler

JDash includes a background notification scheduler that automatically sends EMA reminders to participants based on the survey configuration.

The scheduler runs periodically as a cron job and processes a generated JSON schedule containing:

• Study days on which notifications should be sent

• Activation times configured for survey questions

• Study-specific notification schedules

Workflow

1. Survey activation times are configured in the EMA survey definition.

2. The notification schedule is generated and stored as a JSON structure.

3. The scheduler runs at regular intervals via cron.

4. For each participant, the scheduler calculates the current study day based on the enrollment date.

5. The scheduler checks whether the current study day exists in the generated notification schedule.

6. If a configured activation time falls within the current processing window, a push notification is sent to the participant’s device.

7. Notifications are delivered through Firebase Cloud Messaging (FCM).

Generated Schedule

The scheduler uses a generated JSON file that maps study days to activation times.

Example:

{
   "Study_A": {
      "days": {
         "0": [480, 720],
         "1": [480, 720],
         "2": [480]
      }
   }
}

In this example:

• Day 0: notifications at 08:00 and 12:00

• Day 1: notifications at 08:00 and 12:00

• Day 2: notification at 08:00

This ensures that participants receive reminders relative to their individual enrollment date.

Notification Delivery

Notifications are delivered to enrolled participants through the mobile application and are used to inform users that new EMA questions are available.

Note

Notification schedules are derived directly from the EMA survey configuration. Any changes to survey activation times are automatically reflected in future notification schedules after the schedule is regenerated.

Deployment Instructions

JDash can be deployed locally for development or on a production web server using Apache and mod_wsgi. The latest deployment steps, environment setup, database configuration, and server configuration details are maintained in the official GitHub repository.

https://github.com/Biomarker-Development-at-INM7/JTrack-dashboard