This page is intended for a user who has little to no experience with APIs, and provides a guided walkthrough for working with BCDA using our interactive documentation. More advanced API users may be better served by the Advanced User Guide. If you’re not sure where to go, start here!
Getting Started with APIs
- What’s an API?
- An API (Application Programming Interface) is a set of features and rules that exist inside a software program that allows other software programs to interact with it. For example, you can build an app that uses the Twitter API to get information or data from a user’s Twitter account. APIs are used in a wide variety of ways, but for our purposes, you can think of an API as a pipeline that can allow your ACO’s computer systems to receive data directly from CMS’ databases.
- Need more information about APIs? Here are some great introductions:
- Do I need to know how to code to use BCDA?
- You do not need to know how to code! Our documentation is written so that everyone – regardless of technical exposure – can access beneficiary data. For this walkthrough, we’ll be using a platform called Swagger, where you’ll be able to interact with the API through a web interface.
Setting up your credentials in Swagger
Navigating to Swagger
To get to BCDA’s Swagger page for synthetic data, click on the following link, or copy and paste it into your web browser:
https://sandbox.bcda.cms.gov/api/v1/swagger
Walk-through: from credentials to token
Once the page is open, your first step will be getting an access token. You’ll use this access token later to prove you are allowed to use the API.
- Find the section of the page shown below, in the auth category.
- Click the lock icon.
In the sandbox environment, we provide generic credentials for you to use. These will not work in the production environment, but will allow you to explore the synthetic data in sandbox.
We have provided five sets of synthetic credentials for use in the sandbox, corresponding to various amounts of synthetic beneficiaries. We suggest testing with the credentials that most closely align with the size of your ACO, so that you can get a feel for working with a similar amount of synthetic data to that which you’ll receive in production.
3841c594-a8c0-41e5-98cc-38bb45360d3cf9780d323588f1cdfc3e63e95a8cbdcdd47602ff48a537b51dc5d7834bf466416a716bd4508e904ad5f83f74-6c55-4f1e-9d16-0022688171ba01c23cf3f31f82a5c2dcef5136a8eaa32959158351f4e28aaec5fc6550cb2a5b5d112c5b8aacc4348c75a6f6-02b9-4a47-96c1-0bd6efd4b5e3e1c920141c4aca6b8f726fa8aa0f7b55e095fd1ea3368a5f24b3636fdc907f113d6677977c7259ddf268a8c6-8a29-4d2b-8b92-263dc775750d78ed083ad8e49475f36d04153649012b92c363a538ac97beaf0f7900403989581fc35324baa31e366152afb4-c555-46e4-93de-fa16a441d6431ace5a0e9fdf0c3d713e8c029269eacd024732ccd59e2cf283374e0f8dc93b34429d71b77e55b9a2Back in Swagger, you’ll enter the client ID and secret.
- Click the “Authorize” button when you’ve entered your credentials, then “Close”
Now you’re ready to get a token!
- To show more information about the
/auth/tokenAPI endpoint, click on it (this time, away from the lock icon). - Click “Try it out”
- Click “Execute” to get your token
If all is well, the Server response section will look similar to the following snapshot: it will have a response code of 200, and give an “access_token” in the response body.
- Copy the access token. It will not have any spaces or newlines; the hyphens at the end of the lines are indicating that the line continues unbroken.
Now that you have a token, you can tell Swagger to use it for your future requests.
- Return to the top of the Swagger page
- Click on the lock icon
In the “Value” box:
- First, you must type the word Bearer followed by a space into the box. Bearer is case-sensitive.
- Failure to do this will result in an
HTTP 401 Unauthorizederror.
- Failure to do this will result in an
- Paste your token after the space following Bearer
- Click “Authorize” and then “Close”
You are now ready to interact with the BCDA sandbox environment.
Making your first requests for data
1. Getting comfortable in Swagger
There are two categories of information that you can retrieve through BCDA: metadata, and bulk beneficiary data.
Metadata in BCDA includes information about the platform that is making, storing, and verifying credentials and tokens (the auth provider); information about the API’s version; and information about the actions you can perform using the API itself (also duplicatively termed metadata). There is no PII or PHI in the metadata endpoint, so you can access this endpoint without having to be authorized.
2. Looking at BCDA Metadata
We’ll use auth as an example here.
Under the Metadata endpoint, click on /_auth to expand that section. After the information field expands, as shown below, click Try it out.
Then, as shown below, click Execute to run the process of getting details about auth.
As shown below, clicking Execute returns details about the authorization and authentication provider BCDA is using.
You can repeat this process with the /_version and /api/v1/metadata endpoints as well.
If you’d like to do this from the command line or implement this API call in code, look in the Curl section for the request you just made.
3. Learning about the Bulk Data Resource Types
The bulkData category provides information about beneficiaries. As shown below, there are three pieces of information within the bulkData category. The first one – the Patient endpoint – is an endpoint that returns information about your ACO’s assigned or assignable beneficiaries. The last two pieces of information – jobId and filename – return information about the request you’re making.
Within the Patient endpoint, you can make requests for up to three resource types:
- Explanation of Benefit data includes claims data for your beneficiaries.
- Patient data includes identification information about your assigned or assignable beneficiaries.
- Coverage data includes each beneficiary’s Medicare coverage plan.
4. Making your first request for beneficiary data
To get any bulk beneficiary data, you must first be authenticated with BCDA. Make sure you’ve followed the steps above for Setting up your credentials in Swagger before moving forward.
Retrieving beneficiary data comprises two steps:
- Starting a job to acquire data from the
Patientendpoint - Retrieving data via a job request
a. Making a request for all three resource types
In this example, we’ll show a request for all three resource types in the Patient endpoint. If you want to learn how to make a request for data from one resource type, jump to step 4b: Making a Request for One Resource Type.
First, click on GET /api/v1/Patient/$export, then click Try it out.
Then, as shown below, click Execute to start the process of requesting data from the Patient endpoint. Make sure you note the job number (also known as jobId) in the response header, since you’ll need this job number to track the status of your data request.
If you’d like to use the command line or implement this API call in code, look in the Curl section (shown in the image below) for the request you just made. Not far below that, you can see the response: an HTTP 202 Accepted giving a link in the content-location header for status information on your job.
b. Making a request for one resource type
Next, we’ll show a specific example of requesting only the Coverage resource type from the Patient endpoint. You can follow the same steps for ExplanationOfBenefit or Patient data from the Patient endpoint, or any combination of the three.
First, click on GET /api/v1/Patient/$export, then click Try it out.
As shown above, in the field labeled “Resource types requested,” type “Coverage.” Then click Execute to start the process of requesting Coverage data. Make sure you note the job number (also known as jobId) in the response header, since you’ll need this job number to track the status of your data request.
If you’d like to use the command line or implement this API call in code, look in the Curl section (shown in the image above) for the request you just made. Not far below that, you can see the response: an HTTP 202 Accepted giving a link in the content-location header for status information on your Coverage job.
5. Getting your data
There are two steps to retrieving the requested data:
- Checking the status of your job
- Downloading your bulk data file
Depending on the number of beneficiaries prospectively assigned or assignable to your ACO, it may take a while for your data file to be ready to download. While you wait, you can check the status of your job to find out when the file is ready.
You can check the status of the job by entering the job number into the jobId text field, as shown in the image below.
The X-Progress header indicates the job’s workflow status (Pending, In Progress, Completed, Archived, Expired, Failed). When in the In Progress state, an estimated completion percentage is appended to the X-Progress value (e.g., “In Progress (10%)”).
Once the job is completed, you will receive a HTTP 200 Complete response, which includes a URL ending in .ndjson. You’ll need the end of the URL in order to retrieve your data.
To retrieve your data, open the GET /data/{jobId}/{filename.ndjson} endpoint. Copy the jobId into the jobId field, and the last string of the URL received in the previous step (underlined above) into the filename field, then hit Execute.
The Response Body contains the requested claims data in NDJSON format. Click the Download button that appears in the lower right corner of the response section. Notice that a large file may take a while to download.
If you have requested data related to more than one Resource Type, the files related to each Resource Type will appear separately.
You will have twenty minutes before your token expires, and you will need to get another from /auth/token if it expires before you are finished interacting with the API.
Once you’ve downloaded the file, you’ll want to know what to do with the data. We’ve provided a guide to working with BCDA data to help you, including a crosswalk between CCLF fields and the corresponding sections of the NDJSON files.
Filtering your requests using _since
The _since parameter lets you filter your bulk data requests by the date when the data was updated. This means that instead of receiving all your historical data each time you request data from the API, you will instead be able to enter the date since you last requested data. The API will return data updated between your _since input date and the present. The since parameter can be used with requests for all resource types.
Using the _since parameter comprises three steps:
- Input a date in the correct format
- Start the job to acquire data from an endpoint
- Retrieve data via a job request
a. Input a date in the correct format
First, click “Try it Out” in the Swagger section for GET /api/v1/Patient/export.
Then, enter your desired date into the dialog box labeled “_since (Optional)”. Dates and times submitted in _since must adhere to a specific format for the server to understand. That format is the FHIR instant format (YYYY-MM-DDThh:mm:ss.sss+zz:zz).
The example below demonstrates how to convert a date/time combination into the FHIR format.
Date and Time Example
- Sample Date: February 20, 2020 12:00 PM EST
- instant Format: YYYY-MM-DDThh:mm:sss+zz:zz
- Formatted Sample: 2020-02-20T12:00:00.000-05:00
More information about the FHIR instant format can be found on the FHIR Datatypes page.
b. Start the job to acquire data from that endpoint
To start the job, click Execute.
If you’d like to use the command line or implement this API call in code, look in the Curl section for the request you just made.
Not far below that, you can see the response: an HTTP 202 Accepted giving a link in the content-location header for status information on your job.
c. Getting your data
Follow the previous instructions on for getting your data from an unfiltered request to retrieve your files after a filtered bulk data request.
Have questions?
The BCDA Google Group is the best place to get your questions answered by the BCDA team. In this community you can sign up for feedback session opportunities, get answers to your questions, share your feedback and ideas, and get updates on the project.