**Ratings and Evaluations; Service Connection**

3.303 Principles relating to service connection 3.303-1

3.304 Direct service connection; wartime and peacetime 3.304-1

3.305 Direct service connection; peacetime service before January 1,1947
3.305-1

3.306 Aggravation of pre-service disability 3.306-1

3.307 Presumptive service connection for chronic, tropical, or
prisoner-of-

war-related disease, or disease associated with exposure to certain

herbicide agents; wartime and service on or after January 1,1947 3.307-1

3.308 Presumptive service connection; peacetime service

before January 1 1947 3.308-1

3.309 Disease subject to presumptive service connection 3.309-1

3.310 Disabilities that are proximately due to, or aggravated by,
service-connected

disease or injury 3.310-1

3.311 Claims based on exposure to ionizing radiation 3.311-1

3.312 Cause of death 3.312-1

3.313 Claims based on service in Vietnam 3.313-1

3.314 Basic pension determinations 3.314-1

3.315 Basic eligibility determinations; dependents, loans, education
3.315-1

3.316 Claims based on chronic effects of exposure to mustard gas 3.316-1

3.317 Compensation for certain disabilities due to undiagnosed illnesses
3.317-1

3.318--3.320 \[Reserved\]

3.321 General rating considerations 3.321-1

3.322 Rating of disabilities aggravated by service 3.322-1

3.323 Combined ratings 3.323-1

3.324 Multiple noncompensable service-connected disabilities 3.324-1

3.325 \[Reserved\]

3.326 Examinations 3.326-1

3 327 Reexaminations 3.327-1

3 328 Independent medical opinions 3.328-1

3.329 \[Removed\]

3.330 Resumption of rating when veteran subsequently reports for

Department of Veterans Affairs examination 3.330-1

3.331--3.339 \[Reserved\]

3.340 Total and permanent total ratings and unemployability 3.340-1

3.341 Total disability ratings for compensation purposes 3.341-1

3.342 Permanent and total disability ratings for pension purposes
3.342-1

3.343 Continuance of total disability ratings 3.343-1

3.344 Stabilization of disability evaluations 3.344-1

**§3.303 Principles relating to service connection.**

\(a\) *General*. Service connection connotes many factors but basically
it means that the facts, shown by evidence, establish that a particular
injury or disease resulting in disability was incurred coincident with
service in the Armed Forces, or if preexisting such service, was
aggravated therein. This may be accomplished by affirmatively showing
inception or aggravation during service or through the application of
statutory presumptions. Each disabling condition shown by a veteran's
service records, or for which he seeks a service connection must be
considered on the basis of the places, types and circumstances of his
service as shown by service records, the official history of each
organization in which he served, his medical records and all pertinent
medical and lay evidence. Determinations as to service connection will
be based on review of the entire evidence of record, with due
consideration to the policy of the Department of Veterans Affairs to
administer the law under a broad and liberal interpretation consistent
with the facts in each individual case.

\(b\) *Chronicity and continuity*. With chronic disease shown as such in
service (or within the presumptive period under §3.307) so as to permit
a finding of service connection, subsequent manifestations of the same
chronic disease at any later date, however remote, are service
connected, unless clearly attributable to intercurrent causes. This rule
does not mean that any manifestation of joint pain, any abnormality of
heart action or heart sounds, any urinary findings of casts, or any
cough, in service will permit service connection of arthritis, disease
of the heart, nephritis, or pulmonary disease, first shown as a clearcut
clinical entity, at some later date. For the showing of chronic disease
in service there is required a combination of manifestations sufficient
to identify the disease entity, and sufficient observation to establish
chronicity at the time, as distinguished from merely isolated findings
or a diagnosis including the word "Chronic." When the disease identity
is established (leprosy, tuberculosis, multiple sclerosis, etc.), there
is no requirement of evidentiary showing of continuity. Continuity of
symptomatology is required only where the condition noted during service
(or in the presumptive period) is not, in fact, shown to be chronic or
where the diagnosis of chronicity may be legitimately questioned. When
the fact of chronicity in service is not adequately supported, then a
showing of continuity after discharge is required to support the claim.

\(c\) *Preservice disabilities noted in service*. There are medical
principles so universally recognized as to constitute fact (clear and
unmistakable proof ), and when in accordance with these principles
existence of a disability prior to service is established, no additional
or confirmatory evidence is necessary. Consequently with notation or
discovery during service of such residual conditions (scars; fibrosis of
the lungs; atrophies following disease of the central or peripheral
nervous system; healed fractures; absent, displaced or resected parts of
organs; supernumerary parts; congenital malformations or hemorrhoidal
tags or tabs, etc.) with no evidence of the pertinent antecedent active
disease or injury during service the conclusion must be that they
preexisted service. Similarly, manifestation of lesions or symptoms of
chronic disease from date of enlistment, or so close thereto that the
disease could not have originated in so short a period will establish
preservice existence thereof. Conditions of an infectious nature are to
be considered with regard to the circumstances of the infection and if
manifested in less than the respective incubation periods after
reporting for duty, they will be held to have preexisted service. In the
field of mental disorders, personality disorders which are characterized
by developmental defects or pathological trends in the personality
structure manifested by a lifelong pattern of action or behavior,
chronic psychoneurosis of long duration or other psychiatric
symptomatology shown to have existed prior to service with the same
manifestations during service, which were the basis of the service
diagnosis will be accepted as showing preservice origin. Congenital or
developmental defects, refractive error of the eye, personality
disorders and mental deficiency as such are not diseases or injuries
within the meaning of applicable legislation.

\(d\) *Postservice initial diagnosis of disease*. Service connection may
be granted for any disease diagnosed after discharge, when all the
evidence, including that pertinent to service, establishes that the
disease was incurred in service. Presumptive periods are not intended to
limit service connection to diseases so diagnosed when the evidence
warrants direct service connection. The presumptive provisions of the
statute and Department of Veterans Affairs regulations implementing them
are intended as liberalizations applicable when the evidence would not
warrant service connection without their aid.

\[26 FR 1579, Feb. 24, 1961\]