Trial Information

Text4Diet: A Text Messaging Program for Weight Loss

Background: Text messaging shows promise as an intervention mode for many health conditions
due to its accessibility and timeliness . Few studies have evaluated the effectiveness of
text message-based interventions for weight loss. This study is a randomized controlled
trial comparing an intervention of daily text messaging (Text4Diet) focused on
weight-related behaviors to a control group.

Participant Involvement: One hundred seventy overweight or obese adults will have their
height and weight measured and complete a battery of questionnaires at baseline, 6 and 12
months. Participants in the intervention group will receive on average 4 texts per day
consisting of weight related behavioral recommendations, knowledge based questions, and
prompts to promote physical activity and weight monitoring. Texts are interactive and
personally relevant based upon a baseline questionnaire. The control group will receive only
monthly newsletters but not text messages. Participants in both conditions will receive
monetary compensation for participation, travel to the study site, and reimbursements for
text messaging.

Participants: Inclusion criteria consists of: a) age: 21 to 65 years, b) overweight or
obese status: BMI between 25.0 and 39.9, c) regular access to the Internet, d) own and
regularly use a cell phone and know how to use SMS, d) ability to read and speak English,
and e) ability to participate in moderate PA. Exclusion criteria consists of a) current
pregnancy or the intention of becoming pregnant during the 12 month trial, b) moving out of
the country during the 12 month trial, and c) current eating disorder.

Dates: Recruitment for the RCT began in September 2010. The RCT began in January 2011 and
ended in December 2011. Data analysis will occur through June 2012.

Location: San Diego, CA

Risks to Participants: This study involves low risk. Participation may involve some
discomforts, such as embarrassment from sharing information about home environment, weight,
and technology, diet, and exercise habits. There is a risk of loss of confidentiality of
research information. All risks will be minimized according to the study protocol.