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Workers' Compensation

The SWAG Factor in Workers’ Compensation Cases

The acronym "SWAG" for "Scientific Wild-Assed Guess" first appeared in the 2005 Edition of Workers' Compensation Laws of California (LexisNexis Matthew Bender) (a.k.a. "The Labor Code Book") in Table 18 "Glossary of Terms and Abbreviations Commonly Used in Workers' Compensation".  I first proposed it in the fall of 2004. My editor at the time, Robin Kobayashi, asked me who had used it and in what context did it apply to workers’ compensation?

It was my understanding that Carl Brakensiek, Executive Director of the California Society of Industrial Medicine and Surgery, had used it when addressing their summer convention a few months before. I also provided some instances of it being used online in various listserves.

In any event, that is how SWAG became a new entry in Table 18 of the Labor Code Book as well as the corresponding table in Hanna, California Law of Employee Injuries and Workers' Compensation (LexisNexis Matthew Bender).

When I’ve attended seminars as an exhibitor for my Work Comp Index book, I’ve had judges tell me they had used the term in their "Opinions," e.g., and I'm quoting from memory, “The opinion of Dr. XYZ is not substantial evidence. It is nothing more than that particular doctor's "SWAG" (See Table 18 in the Labor Code Book).”

The SWAG entry in Table 18 cross-references Calif. Labor Code § 4663 & EBM (Evidence Based Medicine).  I added that for the same reason the WCJ quoted the term. If a doctor merely gives an opinion with no "how and why" explaining the basis for their opinion, it deserves to be called a "SWAG."

The main problem I see with a SWAG is that it’s often portrayed as being much more than a "guesstimate," based upon some, but not nearly enough, evidence to be either "probably correct" or even in the right ball park! What distinguishes a SWAG from a reasonable estimate or conclusion is the chain of reasoning connecting the data and the conclusion.  A mass of data simply regurgitated and not connected by a line of reasoning from a premise to a conclusion is not convincing, i.e., not "substantial evidence." In short, it’s a SWAG.

Here are some links that you might find interesting:

  1. An Oklahoma Court of Civil Appeals Judge stated that the water permit at issue was based on a SWAG estimate: See
  2. SWAG was labeled "Quote of the Quarter" on page 4 of the Quarterly Review published by Grancell, Lebovitz, Stander, Barnes and Reubens in their © Fall 2006 issue, citing Table 18 in the 2006 Edition of Workers' Compensation Laws of California. See
  3. The term SWAG was used in HAROLD WEISBERG, Plaintiff-Appellant, v. ALVIN WEISBERG, Defendant-Appellee. No. 210171, COURT OF APPEALS OF MICHIGAN, 1999 Mich. App. LEXIS 2660, where plaintiff said he used the SWAG system for calculating his total out-of-pocket expenses.
  4. The term SWAG was used in the "Public Version" of the Federal Trade Commission's, "In the Matter of CHICAGO BRIDGE & IRON COMPANY....Respondent's Corrected Proposed Findings of Fact and Conclusions of Law" Docket No 9300, page 133, to describe a budget "guesstimate" which is "...not yet based on engineering information from the site, for example, so it can't be a very precise price at that point. (Price, Tr. 604)" See

The following links might amuse you:

  1. Scientific rules of law, including SWAG. See 
  2. "Parachute use to prevent death and major trauma related to gravitational challenge: systematic review of randomised controlled trials (sic)".  The conclusion is: We think that everyone might benefit if the most radical protagonists of evidence based medicine organised and participated in a double blind, randomised, placebo controlled, crossover trial of the parachute.© 2003 by the BMJ Publishing Group, Ltd.