Is Poorly Adjusted Headrests More Dangerous Than No Headrest at All?

[Jobrag]

In the nineteen seventies I remember being told that a badly adjusted headrest was more dangerous then no headrest at all. After an internet search I've not been able to find any evidence that this was correct.
Was this the orthodoxy of the seventies?
Is it still regarded as correct?
Can anyone provide a link to any respectable research?

 

[berkeman]

I googled Car Headrest Adjustment, and got lots of hits. Here is one from CBS News from 2009:

http://www.cbsnews.com/2100-500166_162-575048.html

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