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Quick Survey: The Captcha Mechanism - Utility or Barrier?

Date:  28th July, 2004


In March 2004 I introduced a Captcha device on my comments handler to assist in preventing the growing problem of comment spamming.

The Captcha was fairly well received at the time and has been a non-issue for me ever since.

However, Noah's comments have forced me to question the utility of the Captcha mechanism...

Noah argued against my "attitude to disabled people" and pointed out that I am "making things harder for them... by making them jump through unnecessary hoops". Noah also drew my attention to the fact that I am "cutting out anyone who cannot or choses not to display images".

In responding to Noah's comments, I found that my only real argument in favour of the Captcha (aside from the obvious) was that, "I donít know if I have any disabled readers. I donít know if the Captcha is preventing non-disabled readers from commenting. I have no metrics, no empirical data."

So I'd like to gather a little data here so that I can make an informed decision as to whether the Captcha has real benefits, or if it is simply a barrier to my audience.

  1. Do you browse the with images on or off?
  2. Do you use a non-visual web-browser to access
  3. Do you understand how to use the Captcha mechanism†when posting to the comments handler / forums / emailer?
  4. Do you understand how the Captcha helps to prevent comment spam?
  5. Have you ever attempted to post to the site, only to find that you are unable to complete the process due to the Captcha mechanism?
  6. Have you ever decided not to post because the Captcha hinders you in the process?
  7. Have you registered a user account at specifically to bypass the Captcha mechanism?
  8. Have you ever found that the Captcha system is not working correctly in any way?
  9. Is the Captcha adequately explained on the posting forms?
  10. Is the Captcha image legible?

Thank you in advance for taking the time to respond. Your feedback will help me to improve the Urban Mainframe and make it usable and accessible to as diverse an audience as possible.