What is the Common Working File?

The term Common Working File (CWF) is about as old as any IT terminology in our industry.  I have used it myself since we began the company in 1986.  Despite our common understanding of this concept, I have to admit that I was not really sure what it was, where it was stored, or how it was maintained.  I decided to do a little research. Here are the results.

The CWF is specific to Medicare.  It is a collection of records maintained on behalf of each Medicare beneficiary that covers these four general areas of information:

Entitlement data

Utilization History

Medicare Secondary Payer (MSP)

Health Maintenance Organization (HMO)

This information is stored in a separate record for each beneficiary for each of these data categories.

Although we think of the CWF as a single database, it is actually comprised of 9 databases called Hosts.  Each beneficiary is assigned to only one host.  This is determined by where the person signs up for their SSA benefits.  Here are the host sites and the states that are assigned to each: 

Continue reading

ICD10 to be delayed by one year

Yesterday, March 31, 2014, the senate passed a bill to delay ICD-10 implementation until 10/1/2015.  By a vote of 64 to 35, the Senate voted to delay ICD-10 by at least one year.  The bill is being sent to President Obama where his signature is expected.

This bill includes a suspension of Medicare’s Sustainable Growth Rate (SGR) formula, delaying a 24% cut in physician reimbursement, and delays the Medicare “two midnight” payment policy for hospitals until March of next year.  This was the original content of the bill, it is not clear how or when the ICD-10 delay later became part of this bill.

While the delay in implementing the new ICD-10 code sets helps organizations that were struggling to meet the 10/1/14 deadline, many organizations feel that this legislation is a big step backwards.  The bill actually states that the Department of Health and Human Services cannot adopt the ICD-10 code set until at least 10/1/15, allowing for possible further delays. Continue reading

DDE HIQA Deadline extended

Remember when I said that CMS was eliminating the DDE HIQA screens used for Part A eligibility 4/7/14?  Well, never mind…

CMS has just (2/10/14) announced that this deadline has been suspended.  CMS insists that they will still be terminating the use of these screens, but there is now no set date.  They will announce a date in the future, but they will provide at least 90 days’ notice.

See this article for more information:



By Kalon Mitchell – President, MEDTranDirect

DDE Eligibility to be discontinued 4/7/14


CMS has recently confirmed their original announcement in September of 2012 that they will no longer be supporting the display of Part A eligibility data through DDE screens used by most healthcare providers to view data in the Common Working File.

This is the link to the original announcement that was updated in April of 2013:


Last year, CMS announced their intent to eliminate Part B DDE access and followed through on schedule in April of 2013.

http://info.medtrandirect.com/blog/bid/168065/DDE-CWF-Based-Eligibility-to-Cease-in-April-2013 Continue reading

My DDE is not working!

As some of you know, CMS is transitioning their DDE connectivity to support a new security standard.  I discussed this topic in a previous article, “Direct Data Entry (DDE) Security Upgrade Requirement” on 9/16.  In this article, I mentioned that this upgrade might cause certain provider systems to fail when they attempt to connect to DDE after the transition.  CMS has two separate systems that provide this service, one is managed by HP (Hewlett-Packard) and one is managed by CDS (Companion Data Services). Continue reading

Direct Data Entry (DDE) Security Upgrade Requirement

As most of you know, CMS allows providers direct access to the Common Working File (CWF) through DDE.  This technology has existed for many years and has evolved from remote terminals, modems and phone lines to terminal emulator software running on personal computers connected to the CWF through secure networks.

As this technology evolved, some providers and vendors implemented more modern solutions for their DDE connections, others stuck with existing systems.  Regardless of the technology, the functionality of DDE remained the same.  Once you get connected, everyone sees the same screens and has the same capabilities.  How you got connected made no difference, until now. Continue reading

DDE (CWF) Based Eligibility to Cease in April 2013

HIPAA Eligibility Transaction System (HETS) to Replace Common Working File (CWF) Medicare Beneficiary Health Insurance Eligibility Queries.

If you currently use CWF queries to obtain Medicare health insurance eligibility information for Medicare fee-for service patients, you should immediately begin transitioning to the Medicare Health Insurance Portability and Accountability Act (HIPAA) Eligibility Transaction System (HETS).

To read more:


PayerLink allows you to do unlimited eligibility inquiries for a flat fee of $55/month.