When a military service veteran files a claim for disability compensation with the VA for an illness or disability that resulted from military service, one of the first things a Veteran has to establish is that the current illness or disability is connected to the Veteran's military service. This is called "establishing service connection."
How to Establish Service Connection
There are, generally, five ways to establish service connection. It is important to note that the summary below is very basic. How these five methods of service connection affect your claim, or whether the VA properly considered all applicable methods of service connection, is not covered by this article. For that, you will have to talk to an attorney who practices Veterans Disability Compensation law or a Veterans Service Organization (VSO) that represents Veterans in such matters.
Here are the five methods of establishing service connection for a current disability, disease, or illness.
1. Direct Service Connection. While direct service connection can be established in any number of ways, this generally means there is clear evidence of a disability, an incident that occurred while the veteran was in service, and evidence of “linkage” between the two. The most common example is this: A veteran is currently paralyzed from the waist down. In military service, the veteran suffered an injury in Airborne School and broke his back during a parachute landing. In this example, the veteran's paralysis is directly connected to his military service.
2. Pre-Existing Injury Aggravated by Military Service. In this type of service connection, the veteran had a condition prior to military service, an event occurred in military service, and the event aggravated the pre-existing condition. An example of this is the Veteran that had a skin condition prior to entering military service. However, due to exposure to certain chemicals in the military, the skin condition is made worse than it ever would have been on its own. In situations such as this, the military service is said to "aggravate" the pre-existing condition.
3. Service Connection by Legal Presumption. Certain conditions or diseases are presumed to be service-connected. The VA has lists of these conditions and their presumptive periods. Most of these conditions must manifest to a degree of 10% of more within one year from the date of separation. For example, General Shinseki directed the VA to grant service connection by legal presumption to any Veterans who were exposed to Agent Orange during their military service and who now have Parkinson's disease. Veterans do not have to prove that their current medical condition is related to their military service -- the law presumes it.
4. Secondary Service Connection. This type of service connection exists when one service-connected disability is the cause of another disability. The second disability is not directly related to military service, but would not have occurred but for the first disability (which was caused by military service). A famous case of this type is of a WWII veteran who was treated for tuberculosis using medicine known to cause hearing loss. The hearing loss was service-connected secondarily, through the tuberculosis. Another common present-day example is Diabetes Type II. When Diabetes Type II is service-connected, conditions such as peripheral neuropathy or the panoply of medical conditions caused by Diabetes Type II should be given serious consideration for secondary service connection.
5. Service Connection due to Injury Caused by Treatment in the VA Healthcare System. If a Veteran is injured because of VA hospitalization, treatment, rehab or therapy that is not the fault of the veteran, the injury is treated as service-connected (38 U.S.C. 1151).
You should always talk to a qualified VSO representative or a Veterans Disability Compensation Attorney to determine if your condition can be service-connected in one or more of the above ways, or to find out if a prior VA Ratings Decision is in error because the VA failed to consider all available methods of service connection.
Read more about how Veterans' disability compensation works.