Why it matters for your claim
Evidence of a serious current condition does not necessarily establish what caused it. A service record documenting an injury does not necessarily show a current disability. The three-element framework separates these questions so you can understand what a claim supports and what remains unresolved.
It is especially useful when reading a denial. If VA accepts your diagnosis and an in-service injury but rejects the connection, another copy of the diagnosis may not answer the disputed point. Read the actual reason rather than assuming every denial means VA rejected your whole history.
Where the name comes from
In Caluza v. Brown, 7 Vet. App. 498, 506 (1995), the veterans court described current disability, in-service incurrence or aggravation, and nexus evidence in the context of the former “well-grounded claim” requirement. Congress later removed that preliminary requirement. VA's history of the Veterans Claims Assistance Act discusses both Caluza and that change.
In Shedden v. Principi, 381 F.3d 1163, 1167 (Fed. Cir. 2004), the Federal Circuit stated the three requirements for establishing service connection or service-connected aggravation of a present disability. Shedden also explained that an injury or disease during service does not automatically establish entitlement to compensation for a later disability.
“Caluza triangle” is a teaching label, not a special form or a requirement to buy three documents. The current regulation, 38 CFR 3.303, calls for consideration of service circumstances and the relevant medical and lay evidence. It also allows service connection for a disease first diagnosed after discharge when the evidence establishes that it began in service.
The three elements in plain English
1. A current disability
This asks what disability exists during the relevant claim period. A diagnosis, examination, or treatment record may establish it. Evidence of an old injury that completely resolved does not necessarily establish a current disability.
Avoid the overly broad rule that a named diagnosis is always indispensable. In Saunders v. Wilkie, 886 F.3d 1356 (Fed. Cir. 2018), the court held that pain can qualify as a disability when it causes functional impairment of earning capacity, even without an identified underlying diagnosis. Pain by itself does not guarantee a benefit, and condition-specific requirements still matter.
2. An injury or disease incurred or aggravated in service
This asks what happened during qualifying service. Service treatment records can help, but VA's evidence guidance also recognizes other supporting evidence, including lay statements. A lay statement describes matters a person can competently observe rather than supplying an unsupported medical conclusion.
For Guard and Reserve claims, the exact duty period may be part of the issue. The line-of-duty page explains why a documented incident and qualifying duty status are separate questions. “It happened while I belonged to the Reserves” does not identify the duty status on that date.
3. A connection between the two
The connection is called a nexus. Medical reasoning often matters when the cause is not something a layperson can establish. A report should address the relevant relationship rather than merely restate the diagnosis.
You do not necessarily need a separately purchased nexus letter. Evidence VA obtains may address the connection, and presumptions can change how it is established. Claim Raven's nexus-letter guide explains the purpose of that evidence without treating a private letter as mandatory for every claim.
Where the triangle needs qualification
Presumptive service connection can establish a relationship through qualifying service and a covered condition when the applicable requirements are met. It does not dispense with all evidence. The secondary and presumptive claims guide explains those different paths.
For secondary service connection, 38 CFR 3.310 addresses disability caused or aggravated by an already service-connected condition. The medical relationship being examined is different from the classic direct-service triangle. An increased-rating claim, meanwhile, focuses on the severity of a condition already service connected rather than proving the original connection again.
Service connection and percentage are also separate determinations. Satisfying the direct-service framework does not, by itself, establish a compensable evaluation or the highest available rating. The rating-system guide explains that next question.
Common mistakes
- Treating three headings in a packet as proof that three legal requirements are satisfied.
- Assuming every claim needs a private nexus letter or an in-service diagnosis of the exact later condition.
- Using the same direct-service explanation for a secondary claim without identifying the relevant connection.
- Expecting the triangle to determine the percentage. It concerns service connection, not the full rating analysis.
Questions veterans ask
Are Caluza elements and Shedden elements different tests?
In ordinary claims discussion, both labels refer to the same three-part framework. The cases have different historical contexts, which is why current explanations should not revive Caluza's obsolete preliminary “well-grounded” filing requirement.
What if VA already accepted one of the elements?
Read the favorable findings and the stated reason for denial carefully. Map your existing evidence to the issue still in dispute. The decision-letter guide explains where to find those findings and how they differ from the final result.
Claim Raven explains VA rules in plain English so you can work your own claim. It is not legal advice, and Claim Raven is not affiliated with the Department of Veterans Affairs. Browse every VA term.