Using Implementation Intentions to Self-incentivise Weight-loss

The aim of the present research is to test the effect of helping people to reward themselves when they have successfully lost weight and the impact this will have on subsequent weight. Each participant will be randomly allocated to one of four conditions. The trial requires 200 participants to perform a fully powered statistical analysis. The four conditions are: (1) a control condition, (2) intervention 1 (form a single self-incentivising implementation intention from a drop-down menu), (3) intervention 2 (form multiple self-incentivising implementation intentions from a drop-down menu), or (4) intervention 3 (asked to form a single self-incentivising implementation intention of their own devising). The main outcome measure will be BMI, which will be self-reported.

Study Overview

• Status: Completed
• Conditions: Overweight
• Intervention / Treatment: Behavioral: Single self-incentivising implementation intention; Behavioral: Multiple self-incentivising implementation intentions; Behavioral: Self-generated self-incentivising implementation intentions

• Study Type: Interventional
• Enrollment (Actual): 79
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • Manchester, United Kingdom, M13 9PL
    • University of Manchester
  • Manchester, United Kingdom, M13 9PL
    • Online study

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 100 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Aged 18+

Exclusion Criteria:

• Unable or unwilling to complete questionnaire

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: Control; Participants will be asked to complete a questionnaire.
Experimental: Intervention 1; Single self-incentivising implementation intention After completing a questionnaire, participants will be asked to form a self-incentivising implementation intention: Research shows that rewarding yourself for success can help you to lose weight, but that people often forget to reward themselves. We want you to plan to reward yourself if you achieve your personal weight-loss goal, at the end of 4 weeks. To help you do this, we would like you to complete the following sentence by telling us how you will reward yourself. Please complete the following sentence with a reward of your own choosing. If I lose at least ___lbs/kg by the end of 4 weeks, then I will reward myself by… **Drop down menu** Learning a new skill...	Behavioral: Single self-incentivising implementation intention; Participants are asked to form a single self-incentivising implementation intention (if-then plans)
Experimental: Intervention 2; Multiple self-incentivising implementation intentions After completing a questionnaire, participants will be asked to form self-incentivising implementation intentions: Research shows that rewarding yourself for success can help you to lose weight, but that people often forget to reward themselves. We want you to plan to reward yourself if you achieve your personal weight-loss goal, at the end of 4 weeks. To help you do this, we would like you to complete the following sentence by telling us how you will reward yourself. You can choose as many rewards as you like! Please complete the following sentence with a reward of your own choosing. If I lose at least ___lbs/kg by the end of 4 weeks, then I will reward myself by… and/or… **Drop down menu** Learning a new skill...	Behavioral: Multiple self-incentivising implementation intentions; Participants are asked to form multiple self-incentivising implementation intentions (if-then plans)
Experimental: Intervention 3; Self-generated self-incentivising implementation intentions After completing a questionnaire, participants will be asked to form a self-incentivising implementation intention: Research shows that rewarding yourself for success can help you to lose weight, but that people often forget to reward themselves. We want you to plan to reward yourself if you achieve your personal weight-loss goal, at the end of 4 weeks. To help you do this, we would like you to complete the following sentence by telling us how you will reward yourself. Please complete the following sentence with a reward of your own choosing. If I lose at least ___lbs/kg by the end of 4 weeks, then I will reward myself by…	Behavioral: Self-generated self-incentivising implementation intentions; Participants are asked to form a self-incentivising implementation intention (if-then plans) without a drop-down menu

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Body Mass Index	Self-reported	4 weeks
Actual Use of Self-Rewards	Self-reported	4 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Capabilities, opportunities and motivations	Self-reported	4 weeks

Collaborators and Investigators

• Sponsor: University of Manchester

Study record dates

Study Major Dates

• Study Start (Actual): May 4, 2018
• Primary Completion (Actual): July 25, 2018
• Study Completion (Actual): August 31, 2018

Study Registration Dates

• First Submitted: May 1, 2018
• First Submitted That Met QC Criteria: May 1, 2018
• First Posted (Actual): May 11, 2018

Study Record Updates

• Last Update Posted (Actual): October 23, 2018
• Last Update Submitted That Met QC Criteria: October 19, 2018
• Last Verified: October 1, 2018

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Body Weight; Body Weight Changes; Weight Loss; Overweight
• Other Study ID Numbers: Davids/Coulthard_1

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No