Hwang Kevin O, Ning Jing, Trickey Amber W, Sciamanna Christopher N
Department of Internal Medicine, The University of Texas Medical School at Houston, Houston, TX, United States.
J Med Internet Res. 2013 Jan 15;15(1):e11. doi: 10.2196/jmir.2195.
Online weight loss programs are increasingly popular. However, little is known about outcomes and associations with website usage among members of free online weight loss programs.
This retrospective cohort study examined the association between website usage and weight loss among members of a free commercial online weight loss program (SparkPeople).
We conducted a retrospective analysis of a systematic random sample of members who joined the program during February 1 to April 30, 2008, and included follow-up data through May 10, 2010. The main outcome was net weight change based on self-reported weight. Measures of website usage included log-ins, self-monitoring entries (weight, food, exercise), and use of social support tools (discussion forums, friendships).
The main sample included 1258 members with at least 2 weight entries. They were 90.7% female, with mean (SD) age 33.6 (11.0) and mean (SD) BMI 31.6 (7.7). Members with at least one forum post lost an additional 1.55 kg (95% CI 0.55 kg to 2.55 kg) relative to those with no forum posts. Having at least 4 log-in days, weight entry days, or food entry days per 30 days was significantly associated with weight loss. In the multiple regression analysis, members with at least 4 weight entry days per 30 days reported 5.09 kg (95% CI 3.29 kg to 6.88 kg) more weight loss per 30 days than those with fewer weight entry days. After controlling for weight entry days, the other website usage variables were not associated with weight change.
Weekly or more frequent self-monitoring of weight is associated with greater weight loss among members of this free online weight loss program.
在线减肥项目越来越受欢迎。然而，对于免费在线减肥项目成员的减肥效果以及与网站使用情况之间的关联，人们了解甚少。
这项回顾性队列研究探讨了一个免费商业在线减肥项目（SparkPeople）的成员的网站使用情况与减肥之间的关联。
我们对2008年2月1日至4月30日期间加入该项目的成员进行系统随机抽样，并进行回顾性分析，纳入了截至2010年5月10日的随访数据。主要结局是基于自我报告体重的净体重变化。网站使用情况的衡量指标包括登录次数、自我监测记录（体重、饮食、运动）以及社交支持工具的使用（讨论论坛、好友关系）。
主要样本包括1258名至少有两条体重记录的成员。他们中90.7%为女性，平均（标准差）年龄33.6岁（11.0），平均（标准差）体重指数31.6（7.7）。与没有在论坛发布帖子的成员相比，至少发布过一篇论坛帖子的成员额外减重1.55千克（95%置信区间为0.55千克至2.55千克）。每30天至少有4天登录、记录体重或记录饮食与体重减轻显著相关。在多元回归分析中，每30天至少有4天记录体重的成员比记录体重天数较少的成员每30天多减重5.09千克（95%置信区间为3.29千克至6.88千克）。在控制了体重记录天数后，其他网站使用变量与体重变化无关。
在这个免费在线减肥项目中，每周或更频繁地自我监测体重与更多的体重减轻相关。
