Secondary service connection is an evidence question, not a shortcut to a target combined rating. The record must support the diagnosis, the medical relationship, and the severity under the applicable criteria.
What is a Secondary Condition?
A secondary condition is a disability that was caused or aggravated by a service-connected disability.
Examples:
- Service Connected Back Pain → leads to altered gait → causes Hip or Knee Pain (Secondary).
- Service Connected Tinnitus → causes stress/insomnia → leads to Anxiety/Depression (Secondary).
- Service Connected PTSD → leads to weight gain → causes Sleep Apnea (Secondary). If weight gain is the bridge, use the VA obesity intermediate step checklist to keep the theory clear.
- Medication for a Service-Connected Condition → causes or worsens a diagnosed condition → may support a medication side effects secondary claim.
The Evidence Review
TYFYS can help organize records around a potential secondary theory, but it does not identify guaranteed claims or add ratings. VA applies combined-rating math only after deciding service connection and assigning percentages. If VA assigns one disability at 100% and separate conditions combine to 60%, review the VA SMC-S housebound evidence checklist for the evidence questions. When symptoms overlap with an existing rating, use the VA pyramiding rule evidence checklist to understand whether the evidence shows a distinct impairment or the same manifestation counted twice.
Review a possible secondary theory
Organize the diagnosis, primary service-connected condition, medical reasoning, aggravation evidence, and severity facts before deciding what to file.