Unfortunately, because the federal employees compensation act process makes OWCP's claims actions unreviewable by any court, those running OWCP have created a system that is designed completely for their own convenience, not the convenience of the injured worker. Some years ago, OWCP began to require that medical providers "enroll" in the OWCP system so that they can get a "provider number" from OWCP. Without a provider number, physicians cannot bill OWCP for treating you. Medical providers already need to enroll with and get a number from Medicare. Why OWCP could not use that existing system, and supplement it with their own system for the obscure situation where a provider does not have a medicare number only makes sense if you recall that OWCP is only concerned about making this process convenient for OWCP. The practical effect is that many injured workers have a great deal of trouble finding a medical provider willing to treat them. If you are having difficulty finding someone to treat you, OWCP does have a tool that allows you to search their database for physicians who have provider numbers. If you click on the link below, and click on the "accept" button, then you select that you want to search in the "FECA" program. you can then do a search:
https://owcp.dol.acs-inc.com/portal/providersearch/agreement.do
The search function is fairly straightforward. One limitation is that certain specialties are not broken out. For instance, under specialties, they do not allow you to limit your search to "psychiatrist" or "psychologist". Therefore, to find a specialist who is not categorized, you need to first do a search in the geographic region you are looking in, then, for any physician who does not have a specialty listed, you can google that doctor's name and see whether that doctor is the type of specialist you are looking for.
If you are unable to locate a provider in your region willing to bill OWCP for treating you, you should document that you went through the list and bring this to the attention of your congressman and request a congressional inquiry. This problem is routinely brought to the attention of those running OWCP, they do not seem to be concerned. The only way they will fix this situation is if they receive scrutiny. If a congressman were to conduct hearings on this issue and ask the director of the program to explain why they are unconcerned with this situation, it might get fixed.