Compared to no intervention or minimal interventions (pamphlets, usual care), interactive computer-based interventions are an effective intervention for weight loss and weight maintenance. Compared to in-person interventions, interactive computer-based interventions result in smaller weight losses and lower levels of weight maintenance. The amount of additional weight loss, however, is relatively small and of brief duration, making the clinical significance of these differences unclear.
A randomized trial comparing human e-mail counseling, computer-automated tailored counseling, and no counseling in an Internet weight loss program.
Several studies have shown that e-mail counseling improves weight loss achieved in self-directed Internet programs. Computer-tailored feedback offers a population-based alternative to human e-mail counseling.
                One hundred ninety-two adults, aged 49.2 +/- 9.8 years, having a body mass index (calculated as weight in kilograms divided by height in meters squared) of 32.7 +/- 3.5, were randomized to 1 of 3 Internet treatment groups: No counseling, computer-automated feedback, or human e-mail counseling. All participants received 1 weight loss group session, coupons for meal replacements, and access to an interactive Web site. The human e-mail counseling and computer-automated feedback groups also had access to an electronic diary and message board. The human e-mail counseling group received weekly e-mail feedback from a counselor, and the computer-automated feedback group received automated, tailored messages.
                Retention was 82% at 3 months and 80% at 6 months for all 3 groups. At 3 months, completers in both the computer-automated feedback (-5.3 +/- 4.2 kg) and human e-mail counseling (-6.1 +/- 3.9 kg) groups had significantly greater weight losses compared with the no counseling group (-2.8 +/- 3.5 kg) and these groups did not differ from each other. At 6 months, weight losses were significantly greater in the human e-mail counseling group (-7.3 +/- 6.2 kg) than in the computer-automated feedback (-4.9 +/- 5.9 kg) or no counseling (-2.6 +/- 5.7 kg) groups. Intent-to-treat analyses using single or multiple imputation techniques showed the same pattern of significance.
                Providing automated computer-tailored feedback in an Internet weight loss program was as effective as human e-mail counseling at 3 months. Further research is needed to improve the efficacy of automated computer-tailored feedback as a population-based weight loss approach.