Escobedo — how-and-why apportionment

How later panels applied it

Newest released decisions whose legal-standard extraction named this holding. Each quotes the passage and links to the official PDF. The leading case is cited the way courts cite it; our own cards stay ADJ, date, and issue. Litigated tail — not a win rate.

• ADJ7316783 · 2026-09-24 · Goleta District OfficeEscobedo

  Determinative passage · p.16on an adequate examination and history, and it must set forth reasoning in support of its conclusions.” (Escobedo v. Marshalls (2005) 70 Cal.Comp.Cases 604, 621 (Appeals Board en banc).) “When the foundation of an expert’s testimony is determined to be inadequate as a matter of law, we are not bound by an apparent conflict in the evidence created by his bare conclusions.” (People v. Bassett (1968) 69 Cal.2d 122, 139.) In this case, QME Dr. Stanwyck has failed to assign applicant with any psychiatric work restrictions. In the alternative, Dr. Stanwyck discussed diminished and/or reduced ability to function. Work restrictions are not the same as diminished and/or reduced ability to function. Furthermore, the medical-legal opinions on CVC rebuttal do not constitute substantial medical evidence. To date, Dr. Ovadia continues to defer to Dr.

  Applied to assess the sufficiency of medical-legal opinions in the case.

  Official decision · page 16 →
• ADJ17215880 · 2026-09-18 · Goleta District OfficeEscobedo

  Determinative passage · p.5Marshalls (2005) 70 Cal.Comp.Cases 604, 611 (Appeals Board en banc).) The mere fact that a medical report assigns approximate percentages of industrial and nonindustrial causation does not make the report reliable medical evidence by itself. (E.L. Yeager Construction v. Workers' Comp. Appeals Bd. (Gatten) (2006) 145 Cal.App.4th 922, 927–928 [71 Cal.Comp.Cases 1687].) Rather, the report must disclose familiarity with the concepts of apportionment, describe in detail the exact nature of the apportionable disability, and set forth the basis for the opinion that factors other than the industrial injury at issue caused permanent disability. (Escobedo, at p.

  The QME's opinion was found not to be substantial evidence because it relied on probability and mathematical division without adequate medical or factual support.

  Official decision · page 5 →
• ADJ6958667 · 2026-09-11 · Van Nuys District OfficeEscobedo

  Determinative passage · p.6Pursuant to Labor Code Section 4663, Defendant bears the burden of proving apportionment with substantial evidence. Under Escobedo v. Marshalls (2005) 70 CCC 604, such burden is met if apportionment is supported by substantial medical evidence that explains how and why nonindustrial factors caused a percentage of the applicant's permanent disability. A medical opinion based on materially inaccurate or unresolved historical facts is not substantial evidence. In Pan Pacific Printing Press, Inc. v. WCAB (Whitt) (2016) 81 CCC 744 (writ denied), the QME report could not be relied upon for conclusions dependent on the inaccurate history that applicant had no prior back symptoms. Specifically, in the case of Whitt, "the WCAB explained in its decision that Dr. Broderick's conclusion that Applicant suffered a specific injury on 1/4/2012 was not substantial evidence because it was based on an incorrect history of no prior back injury." Here, Defendant contends that the court erred in declining to apply a 10% non-industrial apportionment based upon the opinions of Dr. Bertoldi and Dr. Sones, which opine that 10% of Applicant's permanent disability should be apportioned to non-industrial factors.

  Defendant failed to meet burden due to inconsistent applicant history and speculative medical opinions.

  Official decision · page 6 →
• ADJ12141593 · 2026-09-11 · Los Angeles District OfficeEscobedo

  Determinative passage · p.10whether it developed from a congenital, developmental, pathological, or traumatic source. (Franklin, supra, at p. 238; see Escobedo v. Marshalls, CNA Ins. Co., (2005) 70 Cal.Comp.Cases 604, 619 (citing Subsequent Injuries Fund v. Workmen's Comp. Appeals Bd. (Talcott) (1970) 2 Cal.3d 56, 62 [35 Cal.Comp.Cases 80].) The first question before us, then, is whether applicant presented substantial medical evidence of preexisting permanent disability under these authorities. (Todd, supra.) To constitute substantial evidence "… a medical opinion must be framed in terms of reasonable medical probability, it must not be speculative, it must be based on pertinent facts and on an adequate examination and history, and it must set forth reasoning in support of its conclusions." (Escobedo, supra.) "Medical opinion … fails to support the Board's findings if it is based on surmise, speculation, conjecture or guess." (Hegglin v. Workmen's Comp. Appeals Bd. (1971) 4 Cal. 3d 162, 169 [36 Cal.Comp.Cases 93, 97].) In this regard, the parties framed the issues for trial to include whether apportionment applies to the 35% or 5% threshold and whether applicant had preexisting permanent disability of unspecified body parts 2 instead of applying the Todd analytical framework. (Minutes of Hearing (Reporter), August 5, 2025, p.

  The Board found Dr. Cortes's opinion met this standard and Dr. Minkstein's did not.

  Official decision · page 10 →
• ADJ10684126 · 2026-09-08 · Santa Ana District OfficeEscobedo

  Determinative passage · p.20(1974) 11 Cal.3d 274 [39 Cal.Comp.Cases 310]; Garza, supra; LeVesque v. Workmen’s Comp. Appeals Bd. (1970) 1 Cal.3d 627 [35 Cal.Comp.Cases 16].) “The term ‘substantial evidence’ means evidence which, if true, has probative force on the issues. It is more than a mere scintilla, and means such relevant evidence as a reasonable mind might accept as adequate to support a conclusion … It must be reasonable in nature, credible, and of solid value.” (Braewood Convalescent Hosp. v. Workers’ Comp. Appeals Bd. (Bolton) (1983) 34 Cal.3d 159, 164 [48 Cal.Comp.Cases 566], emphasis removed and citations omitted.) To constitute substantial evidence “… a medical opinion must be framed in terms of reasonable medical probability, it must not be speculative, it must be based on pertinent facts and on an adequate examination and history, and it must set forth reasoning in support of its conclusions.” (Escobedo v. Marshalls (2005) 70 Cal.Comp.Cases 604, 621 (Appeals Board en banc).) Here, it appears from our preliminary review that the record may not be complete regarding the issues of permanent disability and apportionment. Taking into account the statutory time constraints for acting on the petition, and based upon our initial review of the record, we believe reconsideration must be granted to allow sufficient opportunity to further study the factual and legal issues in this case.

  Applied to evaluate the sufficiency of medical and vocational evidence for apportionment and permanent disability determinations.

  Official decision · page 20 →
• ADJ8507133 · 2026-09-08 · Sacramento District OfficeEscobedo

  Determinative passage · p.6(Gatten) (2006) 145 Cal.App.4th 922, 927–928 [71 Cal.Comp.Cases 1687].) Instead, apportionment of permanent disability is “based on causation” and the “employer shall only be liable for the percentage of permanent disability directly caused by the injury arising out of and occurring in the course of employment.” (Lab. Code, §§ 4663(a) and 4664(a).) “The plain reading of ‘causation’ in this context is causation of the permanent disability.” (Escobedo v. Marshalls (Escobedo) (2005) 70 Cal.Comp.Cases 604, 611 (Appeals Board en banc).) Apportionment now includes pathology, asymptomatic prior conditions, and retroactive prophylactic work preclusions, provided there is substantial evidence establishing that these other factors have caused permanent disability. Pursuant to Escobedo, a physician's opinion must rely on reasonable medical probability, cannot be speculative, must rely on pertinent facts and/or an adequate examination and history, and must set forth the reasoning in support of its

  The WCJ found Dr. Sommer's opinion met this standard and was substantial evidence.

  Official decision · page 6 →
• ADJ21161039 · 2026-09-04 · Santa Ana District OfficeEscobedo

  Determinative passage · p.2II. Petitioner claims that the record lacks substantial medical evidence in support of a finding of injury AOE/COE. Decisions of the Appeals Board must be supported by substantial evidence. (Lab. Code, §§ 5903, 5952(d); Lamb v. Workmen's Comp. Appeals Bd. (1974) 11 Cal.3d 274, 281 [39 Cal.Comp.Cases 310]; Garza v. Workmen's Comp. Appeals Bd. (1970) 3 Cal.3d 312, 317 [35 Cal.Comp.Cases 500]; LeVesque v. Workmen's Comp. Appeals Bd. (1970) 1 Cal.3d 627, 635 [35 Cal.Comp.Cases 16].) Pursuant to section 5705, the “burden of proof rests upon the party or lien claimant holding the affirmative of the issue.” (Lab. Code, § 5705.) “All parties and lien claimants shall meet the evidentiary burden of proof on all issues by a preponderance of the evidence.” (Lab. Code §3202.5.) “A lien claimant... has the burden of proving by a preponderance of the evidence that the claim is industrial....” (Hand Rehabilitation Center v. Workers’ Comp. Appeals Bd.

  The WCJ found Dr. Nikakhtar’s medical opinion met these standards and constituted substantial evidence of injury AOE/COE.

  Official decision · page 2 →
• ADJ19338918 · 2026-09-01 · Oxnard District OfficeEscobedo

  Determinative passage · p.12(Bolton) (1983) 34 Cal.3d 159, 164 [48 Cal.Comp.Cases 566], emphasis removed and citations omitted.) To constitute substantial evidence “… a medical opinion must be framed in terms of reasonable medical probability, it must not be speculative, it must be based on pertinent facts and on an adequate examination and history, and it must set forth reasoning in support of its conclusions.” (Escobedo v. Marshalls (2005) 70 Cal.Comp.Cases 604, 621 (Appeals Board en banc).) Furthermore, the physician must explain the nature of the disease and how and why it is causing disability at the time of the evaluation. (Id.) For the reasons stated by the WCJ, as quoted above, we are persuaded that the opinion of PQME Dr. Greenberg is substantial medical evidence upon which the WCJ appropriately relied on the issues of permanent disability and apportionment. Moreover, conclusions of medical probability do not require an absolute certainty. (McAllister v. Workers’ Comp. Appeals Bd. (1968) Cal.2d 408 [33 Cal.Comp.Cases 660].)

  Dr. Greenberg's opinion was found to meet the substantial evidence standard under Escobedo.

  Official decision · page 12 →