Authorities as the decision cited them, with how this panel applied each one.
E.L. Yeager Construction v. Workers' Comp. Appeals Bd. (Gatten) (2006) 145 Cal.App.4th 922
To be substantial evidence, a medical opinion must be predicated on reasonable medical probability, not speculative, based on pertinent facts and adequate examination, and set forth reasoning in support of conclusions.
The WCJ properly relied on Dr. Gagnon's opinion as substantial medical evidence meeting these criteria.
From the decision · page 2For the reasons stated in the WCJ's report, we agree that the Dr. Gagnon's opinion is
substantial medical evidence upon which the WCJ properly relied. To be considered substantial
evidence, a medical opinion "must be predicated on reasonable medical probability." (E.L. Yeager
Construction v. Workers' Comp. Appeals Bd. (Gatten) (2006) 145 Cal.App.4th 922, 928 [71
Cal.Comp.Cases 1687]; McAllister v. Workmen's Comp. Appeals Bd. (1968) 69 Cal.2d 408, 413,
416§ 17, 419 [33 Cal.Comp.Cases 660].) A physician's report must also 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. (Yeager Construction v. Workers' Comp. Appeals Bd. (Gatten) (2006) 145
Cal.App.4th 922, 928 [71 Cal.Comp.Cases 1687]; Escobedo v. Marshalls (2005) 70
Cal.Comp.Cases 604, 612 (Appeals Board en banc), 70 Cal.Comp.Cases 1506 (writ den.); see also
Milpitas Unified School Dist. v. Workers' Comp. Appeals Bd. (Almaraz-Guzman III) (2010) 187
Cal.App.4th 808 [75 Cal.Comp.Cases 837] [an evaluating physician may deviate from a "strict"
application of the AMA Guides in order to provide a rating within the four corners of the Guides
that more accurately reflects the employee's impairment based on the physician's judgment,
training and experience].)
Labor Code Section 5412
Labor Code Section 5412 defines the date of injury in cumulative trauma cases as the date when knowledge of industrial causation concurs with the date when the employee first suffers disability.
The date of injury was established under this statute based on concurrence of knowledge and disability.
From the decision · page 5The equally critical issue raised by Petitioner is when Applicant first suffered disability from the
cumulative injury. Petitioner argues that Applicant first suffered disability when she self-imposed
a restriction from heavy lifting. The record does not show when she first did so, but it does not
matter: for purposes of satisfying the second prong of 5412, there must be evidence of either
temporary or permanent disability. [Chavira v. WCAB (1991) 56 CCC 631] It is undisputed that
Applicant was never taken off work by a physician for a temporary disability caused by this injury.
Permanent disability was not found until Dr. Gagnon's evaluation on 1/22/2021. It was only then
that there was concurrence of knowledge and disability, thus establishing the 1/22/2021 date of
injury under Labor Sec. 5412.
Milpitas Unified School Dist. v. WCAB (Guzman) (2010) 75 CCC 837
AMA Guides should not be applied mechanically; physicians should use clinical judgment to provide a rating that accurately reflects the actual impairment.
Dr. Gagnon's updated rating was accepted as consistent with this standard allowing clinical judgment.
From the decision · page 6WCAB (Guzman) (2010) 75 CCC 837, where the Court said that the Guides
should not be applied mechanically, "...without regard to how accurately and completely they
reflect the actual impairment sustained by the patient." Instead, said the Court, doctors should use
their "clinical judgment" in evaluating the impairment. I conclude that Dr. Gagnon neglected to
consider these principles, when he prepared his January report and that the April report was
appropriately intended to correct this omission. Consequently, the April report is substantial
evidence in support of my finding of permanent disability in the cumulative trauma case.