A Pilot Randomized Controlled Trial of Financial Incentives, Text Messaging, and Usual Care for Homeless Smokers

Study Overview
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Brief Summary
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The QUIT (Quitting with Usual Care, Incentives, and Technology) Smoking Study is a 3-arm pilot randomized controlled trial that will test the effect of 2 different experimental smoking cessation interventions relative to a control condition in homeless cigarette smokers. All participants will receive free transdermal nicotine patches and weekly in-person smoking cessation counseling. In addition, participants randomized to the first experimental condition will receive financial rewards for biochemically-verified smoking abstinence, and participants randomized to the second experimental condition will be enrolled in a text messaging program to support smoking abstinence.

Official Title
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The QUIT Smoking Study: A Pilot Randomized Controlled Trial of Financial Incentives, Text Messaging, and Usual Care to Help Homeless Smokers Quit Smoking

Conditions
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Smoking

Intervention / Treatment
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* Drug: Transdermal nicotine patch
* Behavioral: In-person smoking cessation counseling
* Behavioral: Contingent financial rewards for smoking abstinence
* Behavioral: Text messages to support smoking abstinence


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Proficient in English, assessed with items asking about native language and self-reported comfort communicating in English among non-native speakers. Age ≥18 years old, assessed by self-report and verified by date of birth. Has smoked ≥100 cigarettes and currently smokes ≥5 cigarettes per day, verified by an exhaled carbon monoxide level of ≥8 ppm. Ready to try quitting smoking within the next month. Currently homeless, assessed by self-report and defined as usually staying in an emergency shelter, transitional shelter, abandoned building, place of business, car or other vehicle, church or mission, hotel or motel, or anywhere outside during the past 7 days. Additionally, individuals will be considered currently homeless if they usually stayed in somebody else's house, apartment/condominium, or room in the past 7 days because of not having their own place to stay. Exclusion Criteria: Currently pregnant, assessed by a urine pregnancy test conducted on all premenopausal biologic females who have not had a hysterectomy, or planning to become pregnant in the next 2 months. Past 30-day use of nicotine replacement therapy, bupropion, or varenicline for smoking cessation, assessed by self-report. Use of bupropion for reasons other than to quit smoking (e.g. depression) is permissible. Prior serious adverse reaction to the nicotine patch, defined as any reaction that was life-threatening or required hospitalization. Heart attack or chest pain within the past 2 weeks. Inability to read a sentence written at a Flesch-Kincaid grade level of 4. Inability to provide informed consent, assessed with knowledge questions about the material presented during the informed consent process that individuals must correctly answer before providing informed consent to participate.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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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: Control (N=25)<br>Transdermal nicotine patch In-person smoking cessation counseling | Drug: Transdermal nicotine patch<br>* ≥10 cigarettes per day: nicotine 21mg/24hr patch daily x 6 weeks, then nicotine 14mg/24hr patch daily x 2 weeks <10 cigarettes per day: nicotine 14mg/24hr patch daily x 8 weeks<br>* Other names: Nicotine;Behavioral: In-person smoking cessation counseling<br>* - One-on-one 15-minute counseling sessions once per week for 8 weeks<br>|
| Experimental: Financial rewards (N=25)<br>Transdermal nicotine patch In-person smoking cessation counseling Contingent financial rewards for smoking abstinence | Drug: Transdermal nicotine patch<br>* ≥10 cigarettes per day: nicotine 21mg/24hr patch daily x 6 weeks, then nicotine 14mg/24hr patch daily x 2 weeks <10 cigarettes per day: nicotine 14mg/24hr patch daily x 8 weeks<br>* Other names: Nicotine;Behavioral: In-person smoking cessation counseling<br>* - One-on-one 15-minute counseling sessions once per week for 8 weeks<br>Behavioral: Contingent financial rewards for smoking abstinence<br>* - Escalating-value financial rewards for smoking abstinence, verified by exhaled carbon monoxide <8ppm<br>* Other names: Contingency management;|
| Experimental: Text messaging (N=25)<br>Transdermal nicotine patch In-person smoking cessation counseling Text messages to support smoking abstinence | Drug: Transdermal nicotine patch<br>* ≥10 cigarettes per day: nicotine 21mg/24hr patch daily x 6 weeks, then nicotine 14mg/24hr patch daily x 2 weeks <10 cigarettes per day: nicotine 14mg/24hr patch daily x 8 weeks<br>* Other names: Nicotine;Behavioral: In-person smoking cessation counseling<br>* - One-on-one 15-minute counseling sessions once per week for 8 weeks<br>Behavioral: Text messages to support smoking abstinence<br>* - 1-5 text messages per day starting up to 2 weeks before the quit date and continuing until 6 weeks after the quit date, delivered by SmokefreeTXT<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Participants With Biochemically-verified Smoking Abstinence, Assessed 14 Times Over 8 Weeks | The primary outcome is a repeated-measures assessment of smoking abstinence, defined as an exhaled carbon monoxide <8ppm and assessed 14 times over the 8-week study period (3 times/week for the first 2 weeks, 2 times/week for the next 2 weeks, and once every week for the last 4 weeks) | Point-in-time abstinence assessed in a repeated fashion 14 times over the 8-week study period | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of Visits Abstinent of Smoking | Percentage of 14 assessment visits at which a participant is abstinent of smoking, defined as an exhaled carbon monoxide level <8ppm. | 8 weeks | 
| Smoking Abstinence at End of Study | Point-prevalence smoking abstinence, defined as an exhaled carbon monoxide level <8ppm, at the 14th (final) study visit. | 8 weeks | 
| Change in Cigarette Consumption | Changes in the average number of cigarettes per day relative to baseline, defined by self-report and repeatedly assessed at the 8 assessment visits occurring on Fridays. | Once per week for 8 weeks | 
| Change in Behavioral Health | Past-month drug use severity (score range 0-1), past-month alcohol use severity (score range 0-1), and past-month psychiatric severity (0-1) were each assessed with the Addiction Severity Index (ASI) - 5th Edition, at baseline and at the 10th and 14th study visits. For each ASI measure, higher scores represent greater drug, alcohol, or psychiatric severity. Changes in ASI scores between baseline and 4 or 8 weeks can range from -1 to +1. When interpreting changes in scores, negative values indicate decreases in scores from baseline to 4 or 8 weeks, and positive values indicate increases in scores from baseline to 4 or 8 weeks. | 4 weeks and 8 weeks | 
| Study Visit Attendance | Percentage of 14 assessment visits attended. | 8 weeks | 
| Counseling Visit Attendance | Percentage of 8 counseling visits attended. | 8 weeks | 
| Nicotine Patch Use | Days of nicotine replacement therapy use in past week, repeatedly measured at the 8 assessment visits occurring on Fridays. | 8 weeks |