Impact of Group Size in Weight Loss Interventions

Improving Weight Loss Maintenance Through Alternatives Schedules of Treatment

The present study will assess whether the size of treatment groups (groups of 10 vs. 30 participants) affects short- and long-term weight loss. It is hypothesized that participants assigned to a small group will exhibit similar short-term and long-term weight losses (i.e., weight loss at months 6 and 12) as compared to those assigned to a large group.

Inclusion Criteria:

• Adults (at least 21 years-old)
• Health insurance coverage with Capital Health Plan (CHP)
• Body mass index BMI between 30-45 kg/m2

Exclusion Criteria:

• BMI is less than 30 kg/m2 or greater than 45 kg/m2
• Weight loss > 10 pounds in past 6 months
• Acute or chronic illnesses for which weight loss is contraindicated
• Unwilling or unable to give informed consent
• Unwilling to accept random assignment
• Unwilling or unable to travel to CHP clinic for assessments and groups
• Likely to relocate out of the area in the next 12 months