Hart Causation & Claims

VA Claims Insights

Weekly plain-language articles on nexus letters, secondary service connection, DIC claims, and the medical evidence behind VA decisions.

VA Claims Insights • C&P Exams & Evidence

Unfavorable C&P Exam Opinion: How an Independent Medical Opinion Responds

September 7, 2026 • 6 min read

When a C&P examiner concludes "less likely than not," the claim is not over. What an independent physician medical opinion can address — rationale, records, and the evidence the examiner did not weigh.

VA Claims Insights • Secondary Service Connection

Depression Secondary to Chronic Pain: What a VA Nexus Letter Must Show

August 31, 2026 • 6 min read

How a physician-authored nexus letter connects depression to a service-connected chronic pain condition: the confirmed diagnosis, the pain-to-mood pathway, and the medical rationale the VA expects.

VA Claims Insights • Secondary Service Connection

Erectile Dysfunction Secondary to PTSD: What a VA Nexus Letter Must Show

August 24, 2026 • 6 min read

How a physician-authored VA nexus letter connects erectile dysfunction to service-connected PTSD or its medications — and the evidence gaps that get these claims denied.

VA Claims Insights • DIC & Survivor Claims

DIC Claims: How a Nexus Letter Closes the Service-Connection Gap After Death

August 20, 2026 • 6 min read

When a veteran was never service-connected for the condition that led to death, the DIC claim stalls on a missing link. What a physician's nexus letter can do.

VA Claims Insights • Secondary Service Connection

Radiculopathy Secondary to a Back Condition: What a VA Nexus Letter Must Show

August 17, 2026 • 6 min read

Nerve pain that radiates from a service-connected spine condition can be rated separately — only when the medical evidence connects it.

VA Claims Insights • Secondary Service Connection

Nexus Letter for Peripheral Neuropathy Secondary to Diabetes: What the VA Needs to See

August 10, 2026 • 6 min read

How a VA nexus letter connects peripheral neuropathy to service-connected diabetes: the confirmed diagnosis, EMG/nerve conduction evidence, the medical rationale, and the "at least as likely as not" standard.

VA Claims Insights • Secondary Service Connection

Migraines Secondary to Tinnitus: How a VA Nexus Letter Connects Them

July 27, 2026 • 6 min read

What a strong VA nexus letter for migraines secondary to tinnitus must address: the confirmed headache diagnosis, the service-connected tinnitus, the medical rationale, and the "at least as likely as not" standard.

VA Claims Insights • Secondary Service Connection

Nexus Letter for Hypertension Secondary to PTSD: What the VA Looks For

July 20, 2026 • 6 min read

How a physician-authored nexus letter connects service-connected PTSD to hypertension, why conclusory opinions get denied, and what the "at least as likely as not" standard requires.

VA Claims Insights • Secondary Service Connection

GERD Secondary to PTSD: What a VA Nexus Letter Must Show

July 20, 2026 • 6 min read

How veterans can support a VA claim for GERD secondary to PTSD with a physician-authored nexus letter: the "at least as likely as not" standard, medical rationale, and common denial reasons.

VA Claims Insights • DIC & Survivor Claims

DIC Claims: How a Cause-of-Death Nexus Letter Helps Surviving Spouses

July 16, 2026 • 6 min read

How a physician cause-of-death nexus letter supports DIC claims when the death certificate does not name the service-connected condition — contributory causes explained.

VA Claims Insights • Direct Service Connection

Nexus Letter for Tinnitus: Why the VA's Most-Claimed Condition Still Gets Denied

July 16, 2026 • 6 min read

Why tinnitus VA claims get denied — delayed onset, missing noise-exposure documentation, weak C&P rationale — and what a strong physician nexus letter must address.

VA Claims Insights • Secondary Service Connection

Nexus Letter for Sleep Apnea Secondary to PTSD: What It Needs to Show

July 14, 2026 • 6 min read

What a strong VA nexus letter for sleep apnea secondary to PTSD must address: the current diagnosis, the service-connected condition, the medical link, and the "at least as likely as not" standard.