Table 3

Results for primary outcomes and conclusions of included studies

Author, year (country)Author's conclusionsConclusions
Booth, 2008 (Australia)PositiveThere was no difference in dietary intake, physical activity and weight loss between the two groups. Goal setting for increasing exercise seems to be more effective than for dietary changes. A larger study with a control group is needed to confirm any findings
Brindal, 2012 (Australia)NeutralSocial networking features did not demonstrate additive effects in terms of weight loss and retention. Greater use of the web tools was associated with greater decrease in weight. More studies are needed to determine why or how this type of intervention can be used to promote weight loss
Carr, 2013 (USA)NeutralThe intervention programme was efficacious at improving physical activity levels in relation to publicly available websites initially, but differences in physical activity levels were not maintained at 6 months. The lack of between-groups differences at 6 months appears to be due to gains in physical activity levels within the control group from 3 months to 6 months rather than decreased physical activity among the intervention group. Testing of future Internet interventions is required
Cavallo, 2012 (USA)NeutralNo increases in perceived social support or physical activity levels were seen over time between groups. However, participant satisfaction with the programme was high
Celio, 2005 (USA)PositiveFindings suggest a modest reduction in weight status and that body image and disordered eating behaviours are not impacted. Low participation with discussion board and food diary noted with a lack of association between compliance and positive outcomes. Interventions with components at a community and public policy level may see more benefit
DeBar, 2009 (USA)PositiveNo significant difference was found for total body BMD but two anatomic areas examined showed a significant difference in favour of the intervention group (spine and trochanter). Authors concluded that a comprehensive multiple component intervention is effective in improving dietary intake and increasing bone mineral density in adolescent girls
Ferney, 2009 (Australia)PositiveThere was a significant interaction effect for total physical activity which suggests efficacy of the neighbourhood-focused website over the control website. Further research is needed to explore effectiveness in a larger sample
van Genugten 2012 (Netherlands)NeutralThe programme resulted in stable weight, and changes in dietary intake in the desired direction, but the tailored intervention was not more effective than generic information. Low compliance with the programme was noted. More research is recommended to gain insight into how this type of intervention can be improved
Gold, 2007 (USA)PositiveThis study showed that participants who received a structured, therapist-led behavioural online intervention lost significantly more weight than those who had access to a self-help commercial weight loss website. Weight loss in both groups was observed only during the first 6 months of the study. There was decreased web usage from months 6 to 12 in both groups
Gow, 2010 (USA)PositiveThe combination of an Internet-based intervention with weight and caloric intake feedback showed promise; however, lower intensity interventions such as the Internet alone were not shown to be effective for preventing weight gain
Harvey-Berino, 2004 (USA)NeutralThe results of this study showed that the Internet was an effective vehicle for promoting long-term clinically significant levels of weight loss. No significant weight loss differences between groups. Further research is warranted
Hurling, 2007 (UK)PositiveA significant increase in physical activity was observed in the intervention group over the control group. Because this was a complex intervention, it is difficult to determine what aspects of the programme contributed most to positive behavioural change; more research is needed to clarify this
Lao, 2011 (USA)NeutralSocial media use did not yield a significant change in each health behaviour goal. These results show multiple challenges persist in stimulating behavioural change with social networking methods in adolescents including lack of engagement and attrition
Micco, 2007 (USA)NeutralMonthly in-person therapy did not improve weight-loss outcomes of an online weight-loss programme. Use declined over the course of the intervention
Morgan, 2011 (Australia)NeutralThis study has demonstrated that men can maintain clinically important and statistically significant weight loss at 12 months following low-dose intervention programmes. Men did not engage in the online discussion board. Additional research needed to determine the optimal balance between online and face-to-face interaction and improve compliance. Less than 50% of men complied with the recommended intervention
Pullen 2008 (USA)PositiveIt is feasible for women aged 50–69 residing in rural areas to access the Internet to lose weight. Low participation was a problem. There is need for research to address this problem
Rydell, 2005 (USA)NeutralA web-based intervention alone may not be effective to change behaviour among youth. They may be useful as part of a multiple component intervention; however, more research is needed to encourage and maintain use of the web-based component
Spittaels, 2007 (Belgium)PositiveIntervention was able to increase physical activity but retention and engagement are important challenges to consider. More research is needed to determine optimal intensity of intervention
Tate, 2001 (USA)PositiveThere was significantly higher weight loss and decrease in waist circumference in the intervention compared with the control; however, no difference in exercise and diet between groups was detected. Low contribution to the discussion board and self-report diary were noted. The Internet seems like a viable intervention method and deserves more research
Tate, 2006 (USA)NeutralEmail counseling improves weight loss compared with educational sites or more interactive sites that include behavioural tools but provide no feedback on behaviour change over time. Further research is needed to enhance these interventions and increase adherence
Webber, 2010 (USA)NeutralBoth groups lost weight over time and there was no significant difference between groups. Poor attendance at group chats was noted. Programme use was associated with more weight loss
Womble, 2004 (USA)NeutralThis study's principal finding was that produced minimal weight loss and was not as effective as a traditional manual-based approach. Participant attendance decreased significantly over the course of the study