Hindsight Bias - Open and Obvious Doctrine 2

ISSUES IN FORENSIC PSYCHOLOGY
Open-and-Obvious Doctrine 2:
Hindsight Bias

After a slip-and-fall episode, ascertaining if a hazard was open-and-obvious is subject to bias. In particular, the "hindsight bias" undermines judgmental accuracy about past events.
A 1990 review defined hindsight bias as "the tendency for people with outcome knowledge to believe falsely that they would have predicted the reported outcome of an event." "Outcome knowledge" refers to knowing what outcome occurred in some set of circumstances (e.g., the plaintiff tripped over a hazard and broke a leg).
Applied to slip-and-fall incidents, the effects of hindsight bias predict that people will overestimate the extent to which a hazard was open-and-obvious. The apparent clarity of past events makes them seem eminently predictable once they have occurred. More often than not, however, they seem this foreseeable only as a result of outcome knowledge.
A previously obscure 1983 study, published in a radiology journal, dramatically demonstrates the effects of hindsight bias. This study obtained chest radiographs, every four months, from 4618 patients at high risk for lung cancer.
During the course of this six-year study, three radiologists found 92 lung tumors in the study group. In the 92 cases of identified turmors, 75 (82%) had initially been overlooked and mistakenly classified as normal.
Subsequent to eventually identifying the previously overlooked tumors, the radiologists found they could return to radiographs previously classified as normal and locate all 75 tumors. Re-examining the previous radiographs resulted in identifying tumors anywhere from 4 to 53 months before they had been originally diagnosed.
In visually identifying these previously missed tumors, the radiologists responded to outcome knowledge. As a result of their outcome knowledge, they knew what type of tumor they were looking for, and where to look for it. This outcome knowledge allowed them to then identify the previously missed tumors.
In other words, the previously missed tumors became visually "open-and-obvious" as a result of outcome knowledge. Without this outcome knowledge, however, those 75 tumors were not open-and-obvious.

If you are dealing with the "open-and-obvious" doctorine, you may want to order a reprint of the following article:

Open-and-obvious under what conditions: American Journal of Forensic Psychology (In press). Order article #22, Cost $12.00).

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