A Behavioral Intervention for Reducing Obesity

Study Overview
=================
Brief Summary
-----------------
This study will examine a contingency management (CM) intervention designed to provide incentives for losing weight versus participating in a manual-guided behavioral weight loss intervention alone. Participants in the CM condition will earn the opportunity to win prizes by losing weight and completing activities that contribute to weight loss, such as keeping daily food and physical activity diaries, choosing healthy foods, exercising, and using other weight loss strategies. The investigators will determine if the CM improves weight loss relative to the usual care manual-guided intervention alone.

Official Title
-----------------
A Behavioral Intervention for Reducing Obesity

Conditions
-----------------
Overweight, Obesity

Intervention / Treatment
-----------------
* Behavioral: contingency management
* Behavioral: weight loss manual-guided individual therapy sessions


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: age between 18 and 65 years body mass index in kg/m2 (BMI) between 30.0 and 39.9 seated blood pressure of 100/60-140/90 mmHg ability to speak English and read at the 6th grade level willingness to be randomly assigned to one of two groups Exclusion Criteria: any serious acute or chronic medical problems that may impact dietary or exercise regimens or impact weight loss psychiatric exclusions

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: A<br>Participants assigned to Group A will receive the LEARN (Lifestyle, Exercise, Attitudes, Relationships, Nutrition) Program weight loss manual and will be instructed to read a section of the manual each week and complete suggested activities. They will also meet with the research staff once a week for weigh-in and supportive counseling. | Behavioral: weight loss manual-guided individual therapy sessions<br>* once weekly counseling sessions with research staff<br>|
| Experimental: B<br>Participants assigned to Group B will receive the LEARN manual and will meet with research staff each week for weigh-in and supportive counseling. They will also receive contingency management or the opportunity to earn draws with the chance of winning prizes for losing weight and completing healthy activities. | Behavioral: contingency management<br>* Prize-based contingency management for weight loss<br>Behavioral: weight loss manual-guided individual therapy sessions<br>* once weekly counseling sessions with research staff<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| absolute and relative weight loss |  | Weeks 1-12 | 
| changes in waist circumference |  | Week 1 and Week 12 | 
| proportion of participants achieving clinically significant weight loss (5% or more of baseline weight) |  | Week 1 and Week 12 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| indices of treatment retention |  | Weeks 1-12 | 
| changes on measures of diet quality, physical activity, and physiological parameters such as blood pressure, lipoproteins, insulin, and glucose levels |  | Week 1 and Week 12 | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Overweight, Obesity, Contingency Management