M21-1 Manual  /  Part VIII, Subpart ii, Chapter 1, Section C

Rating Presumptive Service Connection (SC) Claims for Persian Gulf Veterans

M21-1, Part VIII, Subpart ii, Chapter 1, Section C

Overview

In This Section

This section contains the following topics:
TopicTopic Name
1 Rating Claims for Presumptive SC of Undiagnosed Illness and Medically Unexplained Chronic Multi-Symptom Illness (MUCMI) for Persian Gulf Veterans
2 General Information About Rating Decisions for Undiagnosed Illness and MUCMI Claims
3 Requirements for Providing Adequate Explanation of Decisions on Undiagnosed Illness and MUCMI Claims
4Effective Date Determinations in Undiagnosed Illness and MUCMI Claims

1. Rating Claims for Presumptive SC of Undiagnosed Illness and MUCMI for Persian Gulf Veterans


Introduction

This topic contains information about rating presumptive SC claims of undiagnosed illness and MUCMI for Persian Gulf Veterans, including
  • deciding SC for an undiagnosed illness or MUCMI
  • determining chronicity for qualifying disabilities
  • role of
    • the Veteran’s testimony in establishing signs or symptoms
    • third-party lay evidence in establishing signs or symptoms, and
    • non-medical indicators in establishing signs or symptoms
  • considering Veterans Heath Administration (VHA) Persian Gulf Health Registry examinations
  • rating action to take based on disability pattern determination, and
  • evaluating symptoms of undiagnosed illness and MUCMI as a single or multiple issues.

Change Date

June 6, 2025

VIII.ii.1.C.1.a. Deciding SC for an Undiagnosed Illness or MUCMI

The following information is required to determine whether service connection (SC) under 38 U.S.C. 1117 for an undiagnosed illness or medically unexplained chronic multi-symptom illness (MUCMI) is in order:
  • if the Veteran’s service qualifies for Persian Gulf Veteran status, and
  • whether the disability chronically persisted for at least six months.

Important:

  • Public Law 117-168, Sergeant First Class Heath Robinson Honoring our Promise to Address Comprehensive Toxics (PACT) Act of 2022, added locations qualifying for presumptive SC and removed the requirement for qualifying disabilities that have onset after service to become manifest to a compensable degree. Under the PACT Act, an undiagnosed illness or MUCMI may manifest to a 0-percent disability level and still qualify for presumptive SC.
  • When deciding these claims, it is important that claims processors note which authority (pre-PACT Act or the PACT Act) applies to the claim and explain the basis of the decision, citing relevant favorable findings, regulations, and statutes, as required.

References: For more information on

VIII.ii.1.C.1.b. Determining Chronicity for Qualifying Disabilities

To establish SC for a disability under 38 U.S.C. 1117, the claimed disability must be chronic, that is, it must have persisted for a period of six months. Measure the six-month period of chronicity from the earliest date on which all pertinent evidence establishes that the signs or symptoms of the disability first manifested. Notes:
  • If a disability is subject to intermittent episodes of improvement and worsening within a six-month period, consider the disability to be chronic.
  • Carefully review all evidence, not just the most recent evidence, prior to determining if a claimed disability is chronic.
Reference: For a discussion on the types of evidence that may be accepted to establish objective indications of a chronic disability, see M21-1, Part VIII, Subpart ii, 1.C.1.c-e.

VIII.ii.1.C.1.c. Role of the Veteran’s Testimony in Establishing Signs or Symptoms

When considering disabilities under the provisions of 38 U.S.C. 1117, a Veteran’s lay statement describing his or her own symptoms of a qualifying disability takes on a greater importance than when considering other claims under direct SC principles. First, as indicated in M21-1, Part VIII, Subpart ii, 1.B.2.a, the threshold for ordering an examination for an undiagnosed illness or MUCMI claim is low, as the claimant’s statement alone, describing symptoms, may be sufficient to trigger an examination. Second, lay evidence describing symptoms unsupported by clinical findings is sufficient to establish SC under 38 U.S.C. 1117 as long as there is medical evidence showing that “no medical diagnosis” is present. Important: The Federal Circuit, in Joyner v. McDonald, 766 F.3d 1939 (Fed. Cir. 2014) held that “neck pain,” that was unsupported by physical examination findings or laboratory tests, may establish an undiagnosed illness that causes a qualifying chronic disability. This demonstrates the importance of the Veteran’s testimony, which is essentially all that is needed for the examiner to characterize the symptoms as an “undiagnosed illness” and for SC to be granted, if all other SC requirements are otherwise met. References: For more information on

VIII.ii.1.C.1.d. Role of Third Party Lay Evidence in Establishing Signs or Symptoms

Lay statements from third party lay witnesses that are competent and credible may help establish the presence of objective indications of a chronic disability. Such statements may cover
  • what the Veteran complained of
  • when complaints began
  • how long complaints lasted, and
  • nature/severity of witnessed signs or symptoms.
Reference: For more information on when evidence is competent and credible, see M21-1, Part V, Subpart ii, 1.A.

VIII.ii.1.C.1.e. Role of Non-Medical Indicators in Establishing Signs and Symptoms

Non-medical indicators may help establish signs and symptoms of a qualifying disability. Non-medical indicators may include
  • time lost from work
  • evidence that the Veteran sought medical treatment for their symptoms, and
  • relevant observations, such as changes in the Veteran’s
    • appearance
    • physical abilities, and/or
    • mental or emotional status.

VIII.ii.1.C.1.f. Considering VHA Persian Gulf Health Registry Examinations

In all cases when the Veteran has been examined as part of the Veterans Heath Administration (VHA) Persian Gulf Health Registry, ensure those results have been obtained and considered when rating the Gulf War-related issues. Reference: For more information on developing for the Gulf War Registry examination, see M21-1, Part VIII, Subpart ii, 1.B.1.f.

VIII.ii.1.C.1.g. Rating Action to Take Based on Disability Pattern Determination

The table below shows the rating action to take based on the Department of Veterans Affairs (VA) examiner’s determination of disability pattern.Important:
  • Benefits should only be awarded after taking into consideration the overall evidence of record.
  • Ensure the determination of disability pattern contains the examiner’s supporting rationale.
If the examiner determined the Veteran’s disability pattern to be …Then …
  • an undiagnosed illness, or
  • a diagnosable but medically unexplained chronic multi-symptom illness of unknown etiology
award SC under 38 U.S.C. 1117 if the Veteran meets all 38 U.S.C. 1117 criteria. Reference: For more information on awarding SC for qualifying disabilities under 38 U.S.C. 1117, see M21-1, Part VIII, Subpart ii, 1.C.3.
  • a diagnosable chronic multi-symptom illness with a partially explained etiology, such as diabetes or multiple sclerosis, or
  • a disease with a clear and specific etiology
SC
  • cannot be awarded under 38 CFR 3.317, and
  • may be awarded only if the medical evidence is sufficient to establish SC on a direct or other basis.

Important: In this claim scenario, the examiner must provide a medical opinion regarding toxic exposure risk activity (TERA) participation.

Reference: For more information on deciding claims based on TERA participation, see the PACT Act Implementation Standard Operating Procedure.
Important: As held in Gutierrez v. Principi, 19 Vet.App. 1 (2004) the Veteran is not required to provide nexus evidence linking a qualifying chronic disability to events in service, as long as the Veteran meets all other requirements in 38 U.S.C. 1117. Reference: For more information on handling examination reports that do not contain the required determination of disability pattern, see M21-1, Part VIII, Subpart ii, 1.B.2.p.

VIII.ii.1.C.1.h. Evaluating Symptoms of Undiagnosed Illness and MUCMI as a Single or Multiple Issues

The decision to evaluate multiple symptoms or signs of an undiagnosed illness or MUCMI together as a single issue or separately as multiple issues depends on the outcome most favorable to the Veteran. Although evaluating multiple manifestations under a single body system will in most cases provide the maximum benefit, be alert to symptoms affecting fundamentally different body systems that may clearly warrant separate consideration. Notes:
  • If SC for several symptoms or signs is denied for the same reason, consider such symptoms and signs as a single issue.
  • Assign one hyphenated diagnostic code (DC) on the Codesheet to each issue that is separately considered, whether SC is awarded or denied.
Reference: For more information on assigning a disability evaluation, see M21-1, Part V, Subpart ii, 3.D.

2. General Information About Rating Decisions for Undiagnosed Illness and MUCMI Claims

Introduction

This topic contains general information about rating decisions for undiagnosed illness and MUCMI claims, including
  • proper coding for undiagnosed illnesses and MUCMIs
  • using hyphenated DCs for undiagnosed illnesses and MUCMIs
  • list of appropriate DCs for undiagnosed disabilities and MUCMIs
  • examples of hyphenated codes for undiagnosed disabilities and MUCMIs
  • termination or reduction of benefits previously awarded, and
  • Persian Gulf Veterans’ participation in VA-sponsored research projects.

Change Date

January 29, 2024

VIII.ii.1.C.2.a. Proper Coding for Undiagnosed Illnesses and MUCMIs

In order to properly identify and track disabilities for which SC is awarded or denied, regional offices (ROs) must properly code the undiagnosed disabilities and MUCMIs in the Veterans Benefits Management System - Ratings (VBMS-R) by assigning the
  • 88 DC modifier, and
  • Environmental Hazard in Gulf War special issue.
Reference: For more information on assigning a special issue in VBMS-R, see the VBMS-R User Guide.

VIII.ii.1.C.2.b. Using Hyphenated DCs for Undiagnosed Illnesses and MUCMIs

Use of the hyphenated DC with the 88 DC modifier is required for all awards and denials of undiagnosed illnesses and MUCMIs under 38 U.S.C. 1117. The table below describes each of the codes that comprise a complete hyphenated DC.
CodeDescriptionExample
First DCA 4-digit code created with the 88 modifier as the first two digits. The second two digits are assigned according to the relevant body system.8863, for disabilities awarded or denied under the infectious diseases, immune disorders, and nutritional deficiencies body system
Second DCUse the DC that most closely fits the evaluating criteria.6354, for the applicable evaluation criteria

VIII.ii.1.C.2.c. List of Appropriate DCs for Undiagnosed Disabilities and MUCMIs

The table below lists the first element in a hyphenated code and the type of undiagnosed condition to which each code refers.
If the condition is being evaluated as …And the body system code begins with …Then the first DC of the hyphenated code is …
musculoskeletal diseases508850
amputations518851
joints, skull, and ribs528852
muscle injuries538853
diseases of the eye608860
hearing loss618861
ear and other sense organs628862
systemic diseases638863
nose and throat658865
trachea and bronchi668866
tuberculosis678867
lungs and pleura688868
heart diseases708870
arteries and veins718871
upper digestive system728872
lower digestive system738873
genitourinary system758875
gynecological system768876
hemic and lymphatic system778877
skin788878
endocrine system798879
central nervous system808880
miscellaneous neurological818881
cranial nerve paralysis828882
cranial nerve neuritis838883
cranial nerve neuralgia848884
peripheral nerve paralysis858885
peripheral nerve neuritis868886
peripheral nerve neuralgia878887
epilepsies898889
psychotic disorders928892
organic mental938893
psychoneurotic948894
psychophysiologic958895
dental and oral998899

VIII.ii.1.C.2.d. Examples of Hyphenated Codes for Undiagnosed Disabilities and MUCMIs

The table below contains examples of hyphenated codes that may be used when awarding or denying undiagnosed illnesses manifest by the 13 signs or symptoms or a MUCMI found in 38 CFR 3.317. For the second code, use a DC with rating criteria that most accurately evaluates manifestations of the disability.Note: This list does not contain all possible hyphenated codes.
If the symptom or MUCMI is …Then the hyphenated DC is …
abnormal weight loss8873-7328, (resection of intestine).
cardiovascular signs or symptoms8870-7013, (tachycardia).
cardiovascular signs or symptoms8870-7005, (arteriosclerotic heart disease (ASHD)).
chronic fatigue syndrome8863-6354.
fatigue8863-6354, (chronic fatigue syndrome).
fatigue8877-7700, (anemia).
fibromyalgia8850-5025.
  • gastrointestinal signs or symptoms, or
  • a functional gastrointestinal disorder (FGID)
  • 8873-7305, (ulcer)
  • 8873-7346 (hernia hiatal), or
  • 8873-7319, (irritable bowel syndrome).
headache8881-8100, (migraine headaches).
joint pain8850-5002, (rheumatoid arthritis).
menstrual disorders8876-7622, (uterus displacement).
muscle pain8850-5021, (myositis).
neurologic signs or symptoms8885-85__, (peripheral neuropathy).
neuropsychological signs or symptoms8893-9300, (organic mental disorder).
signs or symptoms involving the respiratory system (upper or lower)
  • 8865-65__, (respiratory system)
  • 8866-66__, (respiratory system), or
  • 8868-68__, (respiratory system).
signs or symptoms involving the skin8878-7806, (eczema).
sleep disturbances8894-9400, (generalized anxiety).
Reference: For more information on the 13 signs or symptoms of an undiagnosed illness or MUCMI, see

VIII.ii.1.C.2.e. Termination or Reduction of Benefits Previously Awarded

Situations may arise that will require termination or reduction of payments previously awarded for undiagnosed illness or MUCMI. Follow the normal procedures for reduction of benefits or severance of SC outlined in M21-1, Part X, Subpart ii, 5.B. Notes:
  • Termination or reduction of benefits paid under 38 U.S.C. 1117 does not preclude continuation of payments if entitlement can be established for SC based on incurrence or aggravation under the provisions of 38 CFR 3.303 and 38 CFR 3.306, respectively, or based on presumption under the provisions of 38 CFR 3.307.
  • The last day of the month 60 days after issuance of the final notice of the adverse action is the last date benefits are payable at the prior rate or, in cases of severance, for the disability. For rating purposes in VBMS-R, enter the first day of the following month as the date of the reduction or severance.
Example: A physician indicates that the Veteran’s condition, which had previously been characterized as an undiagnosed illness and compensated under 38 U.S.C. 1117, is now a clinically diagnosed condition with a clear etiology, and the RO is unable to establish continued entitlement under any other SC provision. After following the due process procedures, a final rating effectuating the severance is prepared on October 10, 2023. As final notice of the adverse action will be sent that same month, the Rating Veterans Service Representative enters January 1, 2024, as the date of severance of compensation for that disability.Reference: For more information on effective dates for reductions of discontinuance of benefits for certain disabilities due to undiagnosed illnesses, see 38 CFR 3.500(y).

VIII.ii.1.C.2.f. Persian Gulf Veterans’ Participation in VA-Sponsored Research Projects

Effective December 27, 2001, 38 U.S.C. 1117 enacted protection of SC for disabilities awarded under 38 U.S.C. 1117 or 38 U.S.C. 1118 for Persian Gulf Veterans who participate in certain VA-sponsored medical research projects. Exception: SC is not protected if the original award was based on fraud, or military records clearly show that the Veteran did not have the requisite service or character of discharge. Note: A list of the relevant VA-sponsored medical research projects for which SC is protected is published in the Federal Register.

3. Requirements for Providing Adequate Explanation of Decisions on Undiagnosed Illness and MUCMI Claims

Change Date

June 6, 2025

VIII.ii.1.C.3.a. Requirement to Provide Adequate Explanation of Decisions

When awarding or denying SC for a condition under 38 U.S.C. 1117, the decision and decision notice must provide adequate reasons for the decision as described in M21-1, Part V, Subpart iv, 1.A.5.a. Important:
  • When denying SC, include
    • a discussion of the specific provisions that were not met under both the presumptive provisions of 38 U.S.C. 1117, as well as any theories of SC raised by the claimant or the evidence, as discussed in M21-1, Part II, Subpart iii, 1.A.2.e, and
    • favorable findings, if applicable, specific to the facts of the case.
  • If the system-generated text options do not adequately cover the reason a claim is being awarded or denied, decision makers must use glossary text or free text to supplement the explanation of the decision.
References: For more information on

4. Effective Date Determinations in Undiagnosed Illness and MUCMI Claims

Introduction

This topic contains information about effective date determinations, including
  • establishing an effective date for undiagnosed illness and MUCMI claims, and
  • examples of 38 U.S.C. 1117 and 38 CFR 3.317 effective dates.

Change Date

June 6, 2025

VIII.ii.1.C.4.a. Establishing an Effective Date for Undiagnosed Illness and MUCMI Claims

When assigning an effective date, follow the guidance in M21-1, Part V, Subpart ii, 4.A relevant to the facts of the claim.In addition to the general principles governing the assignment of effective dates, consider the following relevant factors when awarding SC for an undiagnosed illness or MUCMI:Use the table below to determine which effective date provisions apply.
If the award involves a(n) …And the condition …Then ...
  • undiagnosed illness or MUCMI, and
  • current 38 CFR 3.317 location
manifest to a compensable degreenormal effective date rules applybased on existing 38 CFR 3.317 authority.
did not manifest to a compensable degreethe effective date cannot be prior to August 10, 2022, the date the law was changed to allow for the award of benefits under 38 U.S.C. 1117.Note: If warranted by the facts of the case, apply 38 CFR 3.114(a).
N/Athe effective date cannot be prior to August 10, 2022, the date the law was changed to allow for the award of benefits under 38 U.S.C. 1117.Note: If warranted by the facts of the case, award retroactive benefits under 38 CFR 3.114(a).
Reference: For more information on assigning an effective date, see

VIII.ii.1.C.4.b. Examples: 38 U.S.C. 1117 and 38 CFR 3.317 Effective Dates

Example 1: A Veteran filed a claim for gastrointestinal symptoms on June 2, 2022. Military records show service in a Southwest Asia theater of operations location under 38 CFR 3.317(e)(2). Medical records show a chronic functional gastrointestinal disorder. As the claim could be processed prior to the PACT Act under existing 38 CFR 3.317 authority, the effective date would be the date of claim.Example 2: A Veteran had a previously denied claim for chronic fatigue syndrome in 2019, because even though there were chronic symptoms, they did not meet the minimum compensable criteria under 38 CFR 4.88b, DC 6354. Military records show service in a Southwest Asia theater of operations location under 38 CFR 3.317(e)(2). The Veteran files a supplemental claim on October 2, 2022. Medical records and VA examination continue to show chronic symptoms that would only qualify for a 0-percent evaluation. The claim now qualifies for non-compensable SC because of the new authority in the PACT Act, i.e., removal of the compensability requirement. Therefore, effective date cannot be earlier than the date of the law, August 10, 2022.

Source: VA M21-1 Adjudication Procedures Manual, M21-1, Part VIII, Subpart ii, Chapter 1, Section C (U.S. government work, reproduced for reference). Browse all sections →