Oct 22 2012

Case on Apportionment – “likelihood” vs “reasonable medical probability”

In this case the WCAB ruled that when a physician uses the term “likelihood” it is the same definition as “reasonable medical probability” and the report will not fail based on substantial evidence for using the wrong standard.

Bates v. WCAB (W/D) (77 CCC 636): The WCJ found applicant’s industrial injuries resulted in PD of 100% with no basis for apportionment.  The WCJ rejected the apportionment contained in the AME report, finding the opinion of the AME on apportionment was not based on substantial evidence.  The WCJ had rejected the apportionment contained in the AME report because the AME based his finding on apportionment on a “reasonable likelihood.”  The WCJ ruled that the correct standard for valid apportionment is “reasonable medical probability”.

Defendant filed a Petition for Reconsideration.

WCAB Holding:  The WCAB granted reconsideration. The WCAB indicated that, according to the Random House Dictionary, the word “likelihood” is defined as the state of being likely or probable; probability. The word “probability” is defined as a strong likelihood or chance of something happening. The WCAB indicated that the words “probability” and “likelihood” are synonyms and are used to define each other. The WCAB found the AME had used the correct legal standard.

 Reconsideration and the writ of review was denied.



The WCAB will almost always follow the AME unless the report is found to not be based on substantial evidence.  In this case the WCJ rejected the apportionment based on the fact the AME was not substantial evidence.  The WCAB disagreed and followed the AME.  The general rule today is that the AME is always right!

SB 863 now provides (LC 4062.2) that once you agree to send any issue to an AME, you cannot get a panel QME unless both parties agree in writing to cancel the agreement.

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>