Effectiveness Trial of a Dissonance-Based Obesity Prevention Program

Obesity Clinical Trial

— Project Health  

Official title:

Effectiveness Trial of a Dissonance-Based Obesity Prevention Program

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01680224
• Other study ID #: HD071900
• Status: Completed
• Phase: N/A
• Start date: September 1, 2012
• Est. completion date: May 31, 2018

Study information

• Verified date: September 2018
• Source: Oregon Research Institute
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Obesity is a major US public health problem. Few obesity prevention programs have reduced risk for weight gain over follow-up and those that have are very intensive, making dissemination difficult and costly. A brief 3-hr selective prevention program (Healthy Weight) targeting young adults with body dissatisfaction involving participant-driven healthy dietary and physical activity lifestyle changes significantly reduced increases in body mass index (BMI) and obesity onset relative to alternative interventions and assessment-only controls through 3-yr follow-up, though effects were small in magnitude. To enhance efficacy, the investigators added dissonance-inducing activities regarding unhealthy dietary and activity practices, drawing from a highly efficacious dissonance-based eating disorder prevention program. A pilot trial found that this new Project Health intervention significantly reduced increases in BMI relative to both the Healthy Weight intervention and an educational brochure condition from pre to post. The investigators propose to conduct a rigorous multisite effectiveness trial that will test whether adding the dissonance-induction elements to the originally Healthy Weight intervention improves weight gain prevention effects. 360 college students at risk for future weight by virtue of their age and weight concerns will be randomized one of three conditions: (1) a refined 6-hr group-based dissonance-based Project Health, (2) a 6-hr group-based Healthy Weight intervention, or (3) a psychoeducational video ("Weight of the World") condition. Participants will complete assessments of % body fat, mediators (including objectively measured physical activity), moderators, and other outcomes at pre, post, and 6, 12, and 24 month follow-ups.

Description:

Aim 1 will test the hypothesis that Project Health significantly reduces increases in % body fat relative to the Healthy Weight intervention and video control condition during a 2-yr follow-up; secondary outcomes are BMI, depressive symptoms and eating disorder symptoms. The investigators will also compare Healthy Weight to video controls.

Aim 2 will test the hypothesis that Project Health participants will experience increased cognitive dissonance (an uncomfortable psychological state) regarding eating unhealthy foods and engaging in sedentary behaviors, and that changes in dissonance mediate the program's weight gain prevention effects. The investigators will also test whether reduced calorie intake and increased physical activity mediate the effects of Project Health on change in % body fat.

Aim 3 will test the hypothesis that intervention effects are amplified for participants with elevated body dissatisfaction (which should increase motivation change) and preference for consistency (which should maximize dissonance induction) and mitigated for participants who report emotional eating and substance use (because these factors increase risk for overeating).

Recruitment information / eligibility

• Status: Completed
• Enrollment: 364
• Est. completion date: May 31, 2018
• Est. primary completion date: June 30, 2016
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 17 Years to 23 Years

Eligibility

Inclusion Criteria:

• University student

• Presents with self-reported "weight concerns"

Exclusion Criteria:

• Diagnosis of Eating Disorder

• Obese

• Underweight

• Non-english speaking

Related Conditions & MeSH terms

• Eating Disorders
• Feeding and Eating Disorders
• Obesity
• Weight Gain

Intervention

Behavioral:
• Healthy Weight

• Project Health

• Placebo Control
Participants will view a video on overweight and obesity

Locations

Country	Name	City	State
United States	University of Texas, Austin	Austin	Texas
United States	Oregon State University	Corvallis	Oregon
United States	Oregon Research Institute	Eugene	Oregon
United States	University of Oregon	Eugene	Oregon

Sponsors (1)

Lead Sponsor	Collaborator
Oregon Research Institute

Country where clinical trial is conducted

United States, 

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* Note: There are 93 references in all — Click here to view all references

Outcome

Type	Measure	Description	Time frame	Safety issue
Other	Weighing Habits	Participants will be asked how often they weighed themselves "in the past two weeks" at each assessment.	Baseline and post intervention (6 weeks); 6/12/24 mo follow-ups
Other	Physical Activity	Accelerometers will give objective measures of physical activity from each participant at each wave assessment.	Baseline and post-intervention (6 weeks); 6/12/24 month follow-ups
Primary	Body Fat Percentage	We will use air displacement plethysmography (ADP) via the Bod Pod S/T to assess % body fat. Two measures will be averaged. Body density, calculated as body mass divided by estimated body volume, is used to calculate age- and gender-adjusted body fat percentile scores, based on normative reference data (McCarthy et al., 2006). A pilot validity study (N = 30) revealed that direct DEXA measures of % body fat correlates much more strongly with ADP estimates of body fat (r = .88) than with BMI (r = .23). Change in age- and gender-adjusted body fat percentile over the 2-year follow-up will be the primary outcome. This assessment takes 3-5 minutes to complete.	Changes in body fat from baseline to 2-year follow up
Secondary	Eating Pathology	The Eating Disorder Diagnostic Interview, a brief semi-structured interview, will assess eating disorder symptoms. It provides diagnoses for anorexia nervosa, bulimia nervosa, and binge eating disorder, which will allow us to exclude participants with these disorders. It also provides a continuous measure of overall eating disorder symptoms.	Baseline and post intervention (6 weeks); 6/12/24 month follow-up
Secondary	Negative Affect	The 20-item Negative Affect subscale of the Positive and Negative Affect Schedule (PANAS: Watson et al., 1988) measures general negative affectivity and depressive symptoms. Using a Likert rating system, participants choose their degree of endorsement of negative affectivity items such as "disgusted with self" and "lonely" (response options: 1 = not at all; 5 = extremely).	Baseline and post intervention (6 weeks); 6/12/24 month follow-ups
Secondary	Food Craving/Liking	The 28-item Food Craving Inventory (FCI; White et al., 2002) assesses subjective cravings for individual foods (pasta, ice cream), asking: "Over the past month, how often have you experienced a craving for the food?"	Baseline, 6 weeks (post intervention), 6/12/24 month follow ups