A Medical Source Statement (MSS) is a statement that a doctor fills out with his or her professional opinion regarding the patient’s ability to perform work-related activities and their limitations. This opinion should be based on the patient’s medical history, clinical and laboratory findings (or lack thereof), diagnosis, prescribed treatment and response, expected duration, and prognosis. Medical source statements can be formal or informal.
Formal medical source statements are written on a form that is provided by social security or by your attorney. Informal MSS’ are generic letters describing your abilities and limitations with you doctor’s letterhead at the top.

How is a Medical Source Statement Used?

When a medical source statement is submitted, the Judge or Medical Examiner will review your doctor’s statement. Even though doctors and medical professionals cannot deem you disabled by the government’s standards, their opinions matter and have much weight in your Social Security claim. MSS’ that are up to date and provide detailed information about your work-related limitations can be very helpful to enlighten the judge on how progressed or extreme your conditions are. MSS’ are not required but they are a great bonus to your claim.

How Will You Know if Your Medical Source Statement is a Good One?

The first thing to remember is that you are allowed to provide multiple MSS forms, so long as they are filled out by treating doctors. MSS forms will carry more credibility the more specialized the doctor is and the longer that doctor has treated your conditions. Also, the same doctor can provide multiple MSS forms if your condition has changed over time. It is particularly helpful to get an updated MSS form close to the date of your hearing.
The second thing to remember is that the statement needs to represent the doctor’s honest medical opinion. The doctor’s opinion should be based on your medical history and treatment. You should never ask your doctor to make statements that are untrue. Always be open and honest with your doctor about how you are feeling but never exaggerate your symptoms. If you read your MSS and disagree with your doctor’s answers, you are always welcome to get a second opinion.

And the last thing to remember is once a Medical Source Statement has been filled out by your doctor, it is considered evidence and must be submitted to the judge. Failure to do is considered a serious crime.