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Completed

NCT Number: NCT01311115

Using Group Commitment for Smoking Cessation

This study proposes a novel behavioral intervention to help smokers in Thailand to achieve their goals of quitting. Smoking treatment programs are rare throughout most of Asia and unlikely to meet the impending demand for quitting that tobacco control regulations is stimulating. New approaches are needed.

The present study is a randomized controlled trial to test the effectiveness of a novel, scalable approach to smoking cessation that is targeted toward rural Southeast Asian communities. Thailand is used as a test case to explore if pairs of smokers quit successfully after making financially-backed commitments and receiving cash incentives to quit. The control group receives education and counseling about quitting. In addition to education and counseling about quitting, the intervention includes two key components:

1. Each participant is encouraged to deposit his "cigarette money" on a weekly basis, to be returned only if the smoker quits successfully within three months. Such commitment contracts, based on theory from behavioral economics, are designed to help a person to maintain self-control and motivation in the face of temptation. 2. Each participant is paired with another study participant. If both quit, each receives a cash bonus. The joint incentives are designed to lead partners to support each other throughout the quit attempt.

Thus, group commitment contracts marshal a robust blend of elements: financial commitment, social support, peer pressure, and monetary rewards. A larger, follow-up evaluation will clarify the relative importance of each of these elements.

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Key information

Conditions

Smoking Behavior

Age range

20 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Srinakharinwirot University

Ongkharak, Changwat Nakhon Nayok, 26120, Thailand

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Current smoker of at least 10 cigarettes per week and at least 100 cigarettes over the course of a lifetime
  • Residents of the study area in Nakhon Nayok province, which includes the six subdistricts of Klong Yai, Chumpon, Bueng San, Pak Phli, Khao Phoem, or Ongkharak

Exclusion criteria

  • Pregnant
  • Plans to leave the study area within the next 12 months

Treatment and study plan

Group commitment contract

Behavioral
  • Each participant is required to deposit at least 50 baht at enrollment. A deposit collector visits each participant on a weekly basis and collects additional deposits on a voluntary basis. All deposits are returned only if the smoker quits successfully within three months.
  • The project gives a matching contribution of 150 baht for the initial deposit of at least 50 baht. All participants in the treatment group are further randomized to a one-month group and a three-month group. The one-month group receives an additional 150 baht of project funds if they deposit 100 baht of their money within one month of enrollment. The three-month group receives 150 baht for depositing 100 baht within three months of enrollment.
  • Each participant is paired with another study participant. If both quit, each receives a cash bonus of 1,200 baht. At enrollment, pairs receive brief counseling on ways to support each other during the quit attempt.

Other names: Commitment contract, Deposit contract, Contingency contract, Buddy intervention, Partner intervention

Smoking cessation education and counseling

Behavioral

Participants receive educational pamphlets on reasons to quit smoking and strategies for quitting smoking. They also receive one-time, group counseling on quitting smoking from a nurse trained in smoking cessation counseling.

Other names: Smoking cessation counseling

Primary outcomes

  1. Smoking Status at 6 Months

    Time frame: 6 months after enrollment

    7-day point prevalence of smoking abstinence measured 6 months after enrollment, using a NicCheck urine cotinine test. Participants who self-report having smoked in the last 7 days, as part of the follow-up survey, are considered to be continuing smokers.

Secondary outcomes

  1. Concordance of Smoking Status Between Partners at 6 Months

    Time frame: 6 months after enrollment

    The concordance of smoking status among randomly assigned pairs: both abstain, both smoke, or one abstains and one smokes, measured using 7-day point-prevalence abstinence at 6 months after enrollment, measured using self-reported abstinence and urine cotinine testing. Participants in the control condition are assigned to a pair, but their partner's identity is never revealed during the study.

  2. Smoking Status at 3 Months

    Time frame: 3 months after enrollment

    7-day point prevalence of smoking abstinence measured 3 months after enrollment, using a NicCheck urine cotinine test. Participants who self-report having smoked in the last 7 days, as part of the follow-up survey, are considered to be continuing smokers.

  3. Concordance of Smoking Status Between Partners at 3 Months

    Time frame: 3 months after enrollment

    The concordance of smoking status among randomly assigned pairs: both abstain, both smoke, or one abstains and one smokes, measured using 7-day point-prevalence abstinence at 3 months after enrollment, measured using self-reported abstinence and urine cotinine testing. Participants in the control condition are assigned to a pair, but their partner's identity is never revealed during the study.

  4. Smoking Status at 14 Months

    Time frame: 14 months after enrollment

    7-day point prevalence of smoking abstinence measured 6 months after enrollment, using a NicCheck urine cotinine test. Participants who self-report having smoked in the last 7 days, as part of the follow-up survey, are considered to be continuing smokers.

Sponsors and collaborators

Lead sponsor

University of California, Berkeley

Other

Collaborators

  • Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
  • National Institute on Aging (NIA)
  • Srinakharinwirot University

Registry information

Important dates

Study start
2010
Primary completion
2011
Study completion
2012
First posted
Mar 9, 2011
Registry last updated
Sep 15, 2022

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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