{"page":"https://casescribe.ai/explorer/conditions/undiagnosed-illnesses","generated_at":"2026-10-03T18:34:12.971Z","data_as_of":{"decisions":944125,"first_year":2017,"last_year":2026,"latest_decision":"2026-04-30","cfr":"2026-10-01","m21":"2026-09-29"},"about":{"publisher":"CaseScribe AI (VA Law Explorer)","source":"Public Board of Veterans' Appeals decisions (appeals of VA decisions, not VA's first decisions), M21-1 Adjudication Procedures Manual, 38 CFR Parts 3 and 4.","method":"Outcomes are issue-level: each condition the Board decided in a decision counts once. Decision data is extracted by AI and can contain errors. Rates describe past appeals and do not predict any claim.","disclaimer":"For research only. CaseScribe AI is not a law firm and this is not legal advice. Verify figures against the source decisions and regulations.","attribution":"Cite as: VA Law Explorer, CaseScribe AI, with the page URL."},"data":{"condition":"Undiagnosed illnesses","all_conditions_granted_pct":19.4,"decisions":4547,"years":"2017-2026","granted_pct":20,"denied_pct":33.1,"remanded_pct":46.2,"granted_on_merits_pct":37.7,"by_year":[{"year":2017,"issues":359,"granted_pct":16.2,"denied_pct":40.4,"remanded_pct":40.1},{"year":2018,"issues":602,"granted_pct":15.8,"denied_pct":35,"remanded_pct":45.5},{"year":2019,"issues":594,"granted_pct":14.6,"denied_pct":32.2,"remanded_pct":50.3},{"year":2020,"issues":569,"granted_pct":16.9,"denied_pct":31.1,"remanded_pct":50.8},{"year":2021,"issues":474,"granted_pct":17.9,"denied_pct":31.6,"remanded_pct":49.6},{"year":2022,"issues":547,"granted_pct":20.7,"denied_pct":25,"remanded_pct":53.9},{"year":2023,"issues":557,"granted_pct":20.8,"denied_pct":26.6,"remanded_pct":52.1},{"year":2024,"issues":524,"granted_pct":24,"denied_pct":27.1,"remanded_pct":46.9},{"year":2025,"issues":568,"granted_pct":30.8,"denied_pct":36.8,"remanded_pct":32},{"year":2026,"issues":225,"granted_pct":25.3,"denied_pct":33.8,"remanded_pct":39.6}],"benefit_of_doubt_in_grants_pct":74.6,"evidence_on_merits":[{"evidence":"va_exam_favorable","decisions_with":561,"granted_pct_with":60.8,"granted_pct_without":32.7},{"evidence":"va_exam_unfavorable","decisions_with":3448,"granted_pct_with":34.2,"granted_pct_without":55.9},{"evidence":"nexus_positive","decisions_with":686,"granted_pct_with":64.6,"granted_pct_without":30.4},{"evidence":"nexus_negative","decisions_with":2544,"granted_pct_with":31.8,"granted_pct_without":47.9},{"evidence":"private_opinion","decisions_with":1353,"granted_pct_with":46.6,"granted_pct_without":32.7},{"evidence":"treating_physician","decisions_with":250,"granted_pct_with":60.6,"granted_pct_without":35.9},{"evidence":"lay_statement","decisions_with":3704,"granted_pct_with":34.7,"granted_pct_without":59},{"evidence":"buddy_statement","decisions_with":165,"granted_pct_with":37.4,"granted_pct_without":37.7},{"evidence":"combat_service","decisions_with":369,"granted_pct_with":50.2,"granted_pct_without":36.4}],"top_reasons":{"granted":[{"reason":"current diagnosis established","decisions":49},{"reason":"veteran served in southwest asia during persian gulf war","decisions":44},{"reason":"veteran is a persian gulf veteran","decisions":25},{"reason":"veteran served in southwest asia theater of operations during persian gulf war","decisions":23},{"reason":"veteran qualifies as persian gulf veteran","decisions":19},{"reason":"persian gulf veteran status","decisions":17}],"denied":[{"reason":"no current diagnosis","decisions":452},{"reason":"preponderance of the evidence against the claim","decisions":140},{"reason":"va examiner: less likely than not related to service","decisions":89},{"reason":"current diagnosis established","decisions":87},{"reason":"service records negative or silent","decisions":73},{"reason":"no in-service complaints, treatment or diagnosis","decisions":32}]},"recent_examples":{"granted":[{"case_id":"A26039532","year":2026,"judge":"KRISTY L. ZADORA","rationale":"New and relevant evidence received for readjudication.; Veteran served in Southwest Asia theater during Persian Gulf War.; Diagnosed with chronic fatigue syndrome, gastrointestinal disorder, and irritable bowel syndrome.; Symptoms consistent with medically unexplained chronic multi-symptom illness.;… [truncated, 64 chars omitted]"},{"case_id":"A26038927","year":2026,"judge":"MICHAEL A. HERMAN","rationale":"Death certificate lists myeloid leukemia as sole and immediate cause of death.; Veteran had active service in Southwest Asia theater of operations (July 1992-June 1993).; Chronic myelogenous leukemia is service-connected under 38 C.F.R. § 3.320b for Southwest Asia service."},{"case_id":"A26038782","year":2026,"judge":"S.C. KREMBS","rationale":"Credible evidence establishes PTSD symptoms including impaired impulse control, irritability, and anger.; Veteran and son testified that irritability led to abrupt exit from car, causing fall.; Judicial notice taken that dizziness and irritability are common side effects of Sertraline, prescribed fo… [truncated, 7 chars omitted]"}],"denied":[{"case_id":"A26040564","year":2026,"judge":"JIMMY L. BARDIN","rationale":"No current diagnosis of infectious disease; No symptoms attributable to infectious disease; Evidence persuasively weighs against claim"},{"case_id":"A26040184","year":2026,"judge":"J.W. ZISSIMOS","rationale":"No diagnosis of chronic fatigue syndrome documented.; Fatigue attributed to other service-connected disabilities (PTSD, muscle pain, sleep apnea).; VA examiners found Veteran did not meet criteria for chronic fatigue syndrome."},{"case_id":"26004983","year":2026,"judge":"D. JOHNSON","rationale":"No competent evidence of current CFS diagnosis; Exclusion of other conditions not met; Fatigue symptoms attributed to other diagnoses (HIV, lung cancer, COPD); Severity criteria not met; Lay statements regarding CFS diagnosis are incompetent"}]},"how_va_rates":null,"rules":[]}}