What must be demonstrated for VA to grant a claim for secondary service connection?

To establish a claim for secondary service connection, it is essential to provide evidence that links a primary service-connected condition to a secondary disability. This relationship must demonstrate that the secondary condition is either caused by or aggravated by the primary service-connected disability. The VA requires this causal connection to grant benefits for the secondary condition, as it recognizes that certain disabilities can arise from or be exacerbated by already acknowledged service-related conditions.

In the context of VA claims, simply proving military service or requiring letters of recommendation does not address the needed connection between conditions. Similarly, documentation related to civilian employment does not pertain to establishing the relationship between service-connected and secondary disabilities, which is the primary focus of a secondary service connection claim. Hence, the necessity for evidence linking the primary and secondary conditions directly supports the validity of the claim and is central to the VA's determination process.