Anne Taylor-Vaisey sent me another good article link:
Overcoming Depression on the Internet (ODIN) (2): A Randomized Trial of a Self-Help Depression Skills Program With Reminders, by Greg Clarke, Donna Eubanks, Ed Reid, Chris Kelleher, Elizabeth O'Connor, Lynn L DeBar, Frances Lynch, Sonia Nunley, Christina Gullion, in J Med Internet Res 2005 (Jun 21); 7(2):e16. A note in her e-mail read:
"This is the second randomized trial of the ODIN intervention. In contrast to the first (negative) RCT, which was also published in JMIR, this time investigators added postcard or phone reminders to the intervention arm, to encourage use of the application, and found a statictically significant effect on depression scores. This study is a must-read for eHealth researchers!"