Direct, secondary, and Not sure yet relationships
Direct and secondary service connection ask different questions. Not sure yet is only a Pathfinder organizing label that preserves uncertainty while you review the facts and sources.
Overview
Direct and secondary service connection are different legal theories. Not sure yet is not a VA claim type or legal finding. It is a Pathfinder organizing label that lets you preserve a question without pretending that a relationship is proven. A working choice is not a VA decision Pathfinder can organize the relationship you select and show sources or open questions. It does not establish service connection, diagnose a condition, create a medical nexus, select the legally correct theory, or predict an outcome.
Do this now
Name one current condition or impairment Keep the condition separate from other symptoms and from any possible cause you are still investigating. Write down the possible service connection question Identify the service event, disease, injury, exposure, or already service-connected disability that may be relevant. Name the supporting source Identify the record, firsthand observation, medical evidence, prior VA finding, or qualified opinion that supports the relationship. Preserve what remains uncertain If the facts or source are not ready, choose Not sure yet and write the next question instead of forcing a conclusion. Pathfinder relationship labels organize different questions and do not decide a claim. Working label Question it organizes What it does not mean Direct Is a current disability connected to an event, injury, disease, exposure, or other qualifying fact from service? That every symptom in service proves the current condition is connected. Secondary Did an already service-connected disability cause or aggravate a separate disability? That two associated conditions establish causation or aggravation in this veteran's case. Not sure yet What fact, record, prior decision, or qualified opinion must be reviewed before choosing a working theory? A VA claim category, denial reason, or finding that no relationship exists.
Direct service connection
VA's current evidence guidance describes three recurring parts of an original direct claim: a current physical or mental disability, an event, injury, disease, or qualifying exposure during service, and a link between the current disability and what happened during service. Different evidence may address each part. What exact event, injury, disease, exposure, onset, or worsening is being described? Which service period and duty status were involved? What service record, medical record, order, personnel record, or firsthand statement supports that fact? What is the current diagnosis, disability, or impairment? What evidence addresses the link between the current disability and service? Does a presumption or another service-connection rule need separate review? A diagnosis after discharge can still be reviewed 38 CFR 3.303 explains that a disease first diagnosed after discharge may be service connected when the full evidence establishes that it was incurred in service. That does not mean a later diagnosis is automatically connected. The complete record and the applicable rule still control.
Secondary service connection
38 CFR 3.310 addresses a separate disability that is proximately due to or the result of an already service-connected disease or injury. It also addresses aggravation: an increase in severity of a non-service-connected disability caused by a service-connected disability. VA's claims manual, M21-1 V.ii.2.D (changed May 1, 2026 to follow Spicer v. McDonough), asks whether the increase would not have happened, or the condition would be less severe, but for the service-connected disability, including when it got in the way of treatment. VA no longer considers natural progress in these claims, even though the text of 3.310(b) still mentions it, and the worsening does not have to be permanent. VA still needs a baseline and rates the difference between the baseline and the current severity; an increase too small to change the rating level is granted at 0 percent. Secondary causation and secondary aggravation are separate questions. Secondary question What to review Causation Whether the already service-connected disability caused the separate current disability. Aggravation Whether the separate disability would be less severe but for the already service-connected disability, including when it got in the way of treatment, and the medical evidence of the earlier baseline and the current severity. Which disability is already service connected? What separate current disability is being considered? Is the question causation, aggravation, or both? What treatment history, timing, medication record, examination, or qualified opinion addresses the question? For aggravation, what medical evidence is relevant to the earlier baseline and later increase? What other causes or events should the evidence address? An association creates a question, not a nexus A population-level association, another veteran's result, a medication side-effect possibility, an internet list, or a Theory Bank match does not establish that one condition caused or aggravated another in your case. Preserve it as a research lead until the individual facts and competent evidence support more.
Use Not sure yet when the relationship is not ready
Not sure yet is a safe research state inside Pathfinder. It does not file anything with VA and should never appear as though VA recognizes it as a claim category. Its purpose is to protect accuracy while creating a specific next question. You know the symptoms but do not have a confirmed diagnosis. You remember an event but have not located the service record. More than one service period, duty status, or possible cause may be involved. A possible secondary relationship came from general research rather than a qualified source that reviewed your facts. Records conflict about onset, cause, diagnosis, or worsening. You need to review a prior VA decision before deciding whether the issue belongs in an original or decision-review lane. You simply do not know.
Other service-connection paths exist
Direct and secondary are not the only concepts. Depending on the facts and current law, a condition may involve a presumption, aggravation of a condition that existed before service, qualifying Guard or Reserve duty, toxic-exposure development, or a previously decided issue that belongs in a decision-review lane. A simple relationship map does not replace review of the rule and notice that apply.
Read the Case Map as a sourced hypothesis
Who created the relationship? Distinguish a veteran working choice, verified record observation, clinician statement, prior VA finding, and automated educational pattern. What supports it? Look for a specific document, statement, medical explanation, regulation, or only a general research possibility. What is its status? Keep confirmed facts, veteran-reported facts, disputed items, unanswered questions, and educational possibilities visibly different. Repetition does not make a relationship true A possibility can appear in Claims History, Early Assessment, Case Map, and later summaries without becoming a proven fact. The source and status must travel with the relationship every time it is displayed.
A synthetic example
Suppose a veteran has a current knee diagnosis, remembers a fall during active service, and has a service treatment note documenting knee pain after that fall. The possible direct relationship can be organized around the current condition, the in-service event, and the evidence that addresses the link. Now suppose the same veteran develops a different condition years later and reads that it sometimes occurs in people who change their gait because of knee problems. That research creates a question, but it does not establish a secondary relationship for this veteran. The diagnoses, timeline, alternative causes, and a competent medical explanation may need review. Not sure yet accurately preserves the question.
Use the relationship in Pathfinder
Choose a working relationship in Claims History For a previously denied condition, select Direct, Secondary, or Not sure yet based on the relationship you want Pathfinder to organize. A secondary choice requires an existing service-connected condition as the anchor. The profile records your choice without presenting it as a medical or legal finding. Review the pathway in Early Assessment Check that the condition and pathway label match what you entered. Treat an assessment note as an intake summary, not evidence quality, claim strength, eligibility, or likelihood of success. The roadmap keeps available details and open questions separate. Inspect sources and status in Case Map Open the condition, review the veteran-selected relationship, record observations, Theory Bank possibilities, authority receipts, and built-in limitations. Correct the profile when the working choice is wrong. The relationship remains traceable to its source and can change when better information arrives.
Common mistakes to avoid
Treating Not sure yet as a filing choice on a VA form. Assuming that two conditions appearing together proves causation. Combining secondary causation and aggravation into one unsupported statement. Using a pending, denied, or unrelated condition as though VA has already service connected it. Relying on another veteran's outcome as proof for this veteran. Turning a tool suggestion into a medical nexus opinion. Ignoring a prior decision on the same issue. Selecting every possible theory instead of identifying what the facts currently support.
When the relationship is hard to classify
When the relationship is hard to classify I selected Secondary, but no service-connected condition is available. Confirm whether VA has actually granted service connection for the proposed anchor condition. Check that the granted condition is entered accurately in the profile. Do not use a pending or denied condition as an established secondary anchor. Use Not sure yet until an accurate service-connected anchor and the separate current disability are identified. Research says the two conditions are associated. Identify whether the source describes a general population or this veteran's facts. Separate association from causation and aggravation. Write the specific medical question that still needs an individual explanation. Keep the source as a research lead without presenting it as a nexus conclusion. The records disagree about onset or cause. Record the conflicting dates or explanations without choosing one silently. Check which source created each statement and when. Identify what additional record or qualified review could resolve the conflict. Use Not sure yet and keep the conflict visible in the working map. VA previously decided this same issue. Read the actual decision and notice instructions. Confirm the condition, theory, favorable findings, denial reason, and decision date. Do not assume an original-claim label identifies the valid decision-review option. Preserve the relationship question, but review the decision lane separately before taking action. Return to Claims History or Case Map to correct the working choice. Use the related Claims Guide articles for broader service-connection and medical-opinion guidance.
Official sources
Official sources VA: Evidence needed for a disability claim https://www.va.gov/disability/how-to-file-claim/evidence-needed/ VA: Eligibility for disability benefits https://www.va.gov/disability/eligibility/ 38 CFR 3.303: Principles relating to service connection https://www.ecfr.gov/current/title-38/chapter-I/part-3/subpart-A/section-3.303 38 CFR 3.310: Disabilities caused or aggravated by a service-connected disability https://www.ecfr.gov/current/title-38/chapter-I/part-3/subpart-A/section-3.310 VA M21-1 V.ii.2.D: Secondary service connection and aggravation of non-service-connected disabilities (change date May 1, 2026) https://www.knowva.ebenefits.va.gov/system/templates/selfservice/va_ssnew/help/customer/locale/en-US/portal/554400000001018/content/554400000180484
Related guidance
Related guidance Review the evidence VA describes for different claim types /claims-guide/evidence Compare secondary and presumptive service connection /claims-guide/secondary-presumptive Understand what a qualified medical opinion addresses /claims-guide/nexus-letter Research possible secondary-condition questions /tools/secondary-conditions Describe symptom patterns without using a rating formula /help-center/statements-and-scribe/static-frequency-duration-severity-functional-impact
More information
Return to your saved Pathfinder step Review one condition at a time, keep the working relationship tied to its source, and leave unresolved questions as Not sure yet until the evidence supports a change. Return to Pathfinder /guided-program