> For the complete documentation index, see [llms.txt](https://docs.coupler.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.coupler.io/sources/category/other/castor-edc.md).

# Castor EDC

Castor EDC is a cloud-based electronic data capture platform used in clinical research. It helps research teams design studies, collect patient data through forms and surveys, manage site activity, and maintain full audit trails for regulatory compliance.

Connecting Castor EDC to Coupler.io lets you pull your clinical study data into spreadsheets, data warehouses, or AI tools — without manual exports or custom scripts.

**Why connect Castor EDC to Coupler.io?**

* Automate recurring exports of study data, visit records, and audit trails
* Combine data from multiple entities (e.g., join study forms with field validations) using Coupler.io's Join and Aggregate transformations
* Send data to Google Sheets, Excel, BigQuery, Looker Studio, or AI destinations like ChatGPT, Claude, or Gemini
* Keep stakeholders updated with scheduled refreshes — no manual intervention needed

## Prerequisites

* An active Castor EDC account with API access enabled
* Your Castor EDC **Client ID** and **Client Secret** (used as the API key)
* Knowledge of your account's region (UK, NL, or US) — check your Castor EDC account settings

## Quick start

{% hint style="success" %}
If you're new to Coupler.io, start by creating a data flow with the **Studies** entity to confirm your connection is working, then add more entities as needed.
{% endhint %}

{% stepper %}
{% step %}
**Create a new data flow.** In Coupler.io, click **Add data flow** and search for **Castor EDC** as your source.
{% endstep %}

{% step %}
**Enter your API credentials.** Provide your Castor EDC **Client ID** and **Client Secret**. Then select your **URL region** (uk, nl, or us) — this must match the region where your Castor EDC account is registered.
{% endstep %}

{% step %}
**Set a start date.** Use the date picker to choose the earliest date from which you want to export data. This helps limit the volume of records pulled on the first run.
{% endstep %}

{% step %}
**Select an entity.** Choose the data entity you want to export (e.g., Studies, Study visits, Audit trials). You can add more entities to the same data flow later.
{% endstep %}

{% step %}
**Choose a destination.** Select where you want your data to go — Google Sheets, Excel, BigQuery, Looker Studio, or an AI tool like Claude, ChatGPT, or Gemini.
{% endstep %}

{% step %}
**Run the data flow.** Click **Run** to execute a manual sync and confirm that data is flowing correctly.
{% endstep %}
{% endstepper %}

## Available entities

| Entity                   | Description                                     |
| ------------------------ | ----------------------------------------------- |
| Users                    | Platform users and account information          |
| Studies                  | Clinical studies and research projects          |
| Audit trials             | System changes and user activity logs           |
| Countries                | Countries available in the system               |
| Study surveys            | Surveys associated with studies                 |
| Study survey packages    | Packages containing multiple surveys            |
| Study sites              | Physical locations where studies are conducted  |
| Study fields             | Data fields and form elements within studies    |
| Study field dependencies | Relationships between study fields              |
| Study field validations  | Validation rules applied to study fields        |
| Study forms              | Forms used for data collection                  |
| Study roles              | User roles and permissions within studies       |
| Study fieldoption groups | Groups of options for dropdown/selection fields |
| Study statistics         | Statistical metrics for studies                 |
| Study users              | Users assigned to studies and their permissions |
| Study visits             | Patient visits and appointments within studies  |


---

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