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General Usability DetecVS tor

From: Gregg Vanderheiden <gv@trace.wisc.edu>
Date: Sun, 9 May 2004 23:46:54 -0500
To: <w3c-wai-gl@w3.org>
Message-ID: <auto-000031609312@spamarrest.com>
In discussions on our last call "usability" came up since it was a question
from one of our reviewers


How do we separate

"Accessibility / Usability problems that are specific to disabilities" 


"usability issues that are faced by all users"



One test I have sometimes found useful in examining this question is 

   "Does it multiply the time and effort for people with disabilities by the
same amount as people without disabilities?"

If the multiplier is the same - then it may be a general usability issue.


For example

Good page    2 min  for  no disability

Good page    4 min for screen reader user


Bad page      3 min for no disability

Bad page       6 min for screen reader user


This bad page appears to be 50% harder for both groups.   This looks more
like a general usability problem rather than accessibility since it slows
everyone down by the same factor



Another example


Good page   2 min for no disability 

Good page   4 min with screen reader


Page 2  -    3 min for no disability

Page 2  -    10 min   with screen reader. 


Page 3  -    3 min for no disability

Page 3  -     cannot get at some of the information with screen reader. 


These look like accessibility problems 

Page 2 is much more than proportionately harder (250% vs 50%)

Page 3 is inaccessible 



Just passing along in case it is of use to others in thinking about the





Gregg C Vanderheiden Ph.D. 
Professor - Depts of Ind. Engr. & BioMed Engr.
Director - Trace R & D Center 
University of Wisconsin-Madison 
< <http://trace.wisc.edu/> http://trace.wisc.edu/> FAX 608/262-8848  
For a list of our list discussions http://trace.wisc.edu/lists/



Received on Monday, 10 May 2004 00:47:16 UTC

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