Understanding Mechanisms of Health Behavior Change

Not Applicable

Completed

• Conditions: Diet Modification; Overweight and Obesity; Incentives
• Interventions: Behavioral: self-monitoring; Behavioral: delayed lump sum monetary incentives; Behavioral: daily monetary incentives

• Registration Number: NCT03192254
• Lead Sponsor: University of Colorado, Boulder

Brief Summary

This research seeks to examine psychological factors that may impact relationship between incentives and health behavior engagement, specifically fruit and vegetable consumption. Additionally, it will compare the impact of two different incentive schedules on behavior engagement, one providing immediate rewards (i.e. rewards received on a daily basis) and another providing delayed rewards (i.e. rewards received at the end of the study period), with a control condition in which no rewards are offered. Study participants will provide reports of their fruit and vegetable consumption each day for three weeks, and in the two incentive conditions, they will receive small monetary rewards for their fruit and vegetable consumption. Following the three week reporting and reward period, participants will complete two additional assessments, measuring psychological constructs and behavior engagement following the cessation of rewards. The study will also examine how cognitive and anthropomorphic factors may contribute to intervention response and the effects on psychological constructs.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2017-06-16
• Study First Submitted QC: 2017-06-16
• Study First Posted: 2017-06-20
• Study Start: 2017-07-13
• Primary Completion: 2018-02-21
• Study Completion: 2018-03-30
• Status Verified: 2023-07
• Last Update Submitted: 2023-07-27
• Last Update Posted: 2023-08-01

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 68

Inclusion Criteria

• Consume fewer than 3 servings/day of fruits and vegetables
• Daily access to internet for 3 weeks following baseline session
• Have or are willing to create an account on PayPal
• BMI greater than or equal to 25, from self-reported height and weight

Exclusion Criteria

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Self-Monitoring Control	self-monitoring	Daily tracking of fruit and vegetable consumption
Daily Incentives	self-monitoring	Incentives for fruit and vegetable consumption delivered daily
Delayed Lump Sum Incentives	self-monitoring	Incentives for fruit and vegetable consumption delivered in a lump sum at the end of the intervention
Delayed Lump Sum Incentives	delayed lump sum monetary incentives	Incentives for fruit and vegetable consumption delivered in a lump sum at the end of the intervention
Daily Incentives	daily monetary incentives	Incentives for fruit and vegetable consumption delivered daily

Primary Outcome Measures

Name	Time	Method
Perceived behavioral control scale score	5 Weeks
Attitude scale score	5 Weeks
Fruit and vegetable consumption, servings per week	5 Weeks

Secondary Outcome Measures

Name	Time	Method
Intrinsic motivation scale score	5 Weeks

Trial Locations

Locations (1)

University of Colorado Boulder; 🇺🇸 Boulder, Colorado, United States