If you want to make interception more difficult, use an SSL connection. Then it will at least be sent encrypted.
Or let those doctors e-mail it to you directly, without using the webpage.
pritaeas
Posting Prodigy
9,280 posts since Jul 2006
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Imo, CAPTCHA will not serve your purpose much. SSL is the best way. Find it expensive? I guess if so, there's the alternative of making your own SSL (but then users viewing a warning may be a downside).
reganstar
Junior Poster in Training
72 posts since Apr 2009
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Capthcha is used to avoid spam generated by bots, it can not defeat or restrict a human.
urtrivedi
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