Changing Impulsivity With Mindful Breathing Therapy to Reduce Problem Drinking (BBMT)
Primary Purpose
Problem Drinking
Status
Completed
Phase
Not Applicable
Locations
United States
Study Type
Interventional
Intervention
Mindfulness Therapy
Sponsored by
About this trial
This is an interventional treatment trial for Problem Drinking focused on measuring Mindfulness, Therapy, Problem Drinking, Breathing-based mindfulness training
Eligibility Criteria
Inclusion Criteria:
- UM College Park students aged 18-30
- AUDIT score of 8 or higher (Babor et al., 2004)
- A total score on the Barratt Impulsiveness Scale of 73 or higher, which is the mean plus half (1/2) standard deviation, (M=64; SD=17) (Patton et al., 1995)
- A commitment to adhere to the study protocol with a weekly therapy meeting (about 40 minutes each), and an extra 1.5 to 2 hours for study data collection at week 4 and week 8
- No plan to move away from the UM campus area for next 2 months
Exclusion Criteria:
- At current risk of suicide, including suicidal behavior or attempts in the past 30 days
- A history of schizophrenia or other psychotic disorders
- Current participation in other clinical studies of addiction or impulsive behavior
- Severe physical and mental health problems
Sites / Locations
- 2103 Cole Field House
Arms of the Study
Arm 1
Arm Type
Experimental
Arm Label
Mindfulness Therapy
Arm Description
For the current study the investigators have developed a breathing-based, adapted for feasible application among SUD populations, and easy to carry out in clinical or non-clinical settings referred to as breathing-based mindfulness training (BBMT). BBMT is a simplified form of MM. Its core components are near resonance-frequency breathing (RFB), mindfulness training, positivity and inward attention (more details below).
Outcomes
Primary Outcome Measures
Changes in substance use utilizing the Timeline Follow Back from the baseline to 3 months
Timeline Follow-back (TLFB) (C. Sobell & B. Sobell, 1992) will be used to record and track participants' recent (past 30 days and 7 days) alcohol-use as well as other drug use frequency. Alcohol-use and other drug use quantity will be recorded for each day on which use was reported. The TLFB method has been shown to have good reliability and validity in college students (Sobell et al., 1989)
Secondary Outcome Measures
Audit
Alcohol Use Diagnostic Identification Test (AUDIT) (Babor et al., 2004), has 10 items which assess frequency of drinking, typical quantity, frequency of heavy drinking, impaired control over drinking, increased salience of drinking, morning drinking, blackouts, and alcohol-related injuries within the past year. A total score of 8 or more has been found to indicate a strong likelihood of hazardous or harmful alcohol consumption
Readiness to Change
Readiness to Change: Drug and Alcohol version of SOCRATES (Miller & Tonigan, 1996) will be used to evaluate motivation for change
Customary Drinking and Drug Use Record
Customary Drinking and Drug Use Record (CDDR; Brown et al., 1998) measures lifetime alcohol use and problems to provide a baseline and examine the impact of treatment. The CDDR records age at first use and makes separate lifetime frequency use estimations for beer, wine, and distilled spirits. The CDDR has good reliability for assessing substance use behaviors among adolescents and young adults (Brown et al., 1998) and has been used specifically in college-student samples Doran et al., 2007)
Barratt Impulsiveness Scale
Barratt Impulsiveness Scale (BIS-11) , includes questions focusing on motor impulsivity (acting without thinking), cognitive impulsivity (making quick cognitive decisions), and future-planning impulsivity (lack of concern about the future), with good internal consistency (alpha = 0.89 to 0.92) and test-retest reliability (0.80). Mean plus one SD in total BIS score from UM study (M = 64; SD = 17) will be used to screen and select those with high impulsivity to be included in this study to assess possible change over time.
UPPS Impulsive Behavioral Scale
UPPS Impulsive Behavior scale (Whiteside & Lynam, 2001) assesses five personality pathways to impulsive behavior: negative urgency, positive urgency, (lack of) premeditation, (lack of) perseverance, and sensation seeking
Delay Discounting of Hypothetical Money Gains
Delay Discounting of Hypothetical Money Gains, is a computerized binary-choice procedure. On each trial, two outcomes will be presented on the screen: one is an amount of money available immediately; the other is a larger amount of money ($50, $1,000) available after some delay (1 week, 1 year, etc.). The computerized algorithm (Holt et al., 2003) will adjust the immediate outcome for each amount/delay pairing over 6 trials to determine an indifference point, resulting in 6 indifference points (corresponding to the 6 delays) for each of 2 amounts ($50, $1,000).
Stop-Signal Task (SST)
A personal computer will be used to conduct the SST, which presents two types of trials: GO and STOP. In GO trials, participants will respond with a keystroke as quickly as possible following the presentation of a visual go stimulus. In STOP trials (25% of all trials), an auditory stop signal will follow the presentation of the visual go signal. Subjects will be instructed to inhibit the go response on hearing the stop signal. The latency between onset of the go and stop signals will be titrated in the following manner: failure on a STOP trial will result in a 50ms increase in this latency, and success will result in a 50ms decrease. This method will converge on a latency, the stop signal delay (SSD) at which a participant succeeds on half of all STOP trials. After 16 GO practice trials, participants will complete five blocks of 64 trials.
Spielberger State-Trait Anxiety Inventory (STAI):
both trait and state anxiety will be measured monthly to monitor changes over time
The Center for Epidemiological Studies Depression Scale (CES-D)
The Center for Epidemiological Studies Depression Scale (CES-D) (Radloff, 1977) is a 20-item self-report inventory measuring mood and symptoms of depression.
Perceived Stress Scale
Perceived Stress Scale is a global measure of perceived stress in daily life (Chiang et al., 2005) designed to gauge the degree to which common situations are appraised as stressful
Difficulties in Emotion Regulation Scale (DERS; Gratz & Roemer, 2004)
Difficulties in Emotion Regulation Scale (DERS; Gratz & Roemer, 2004) is a well-validated 36-item, self-report questionnaire that assesses multiple aspects of emotion dysregulation. The DERS yields a total score that is comprised of scores on six subscales: nonacceptance of emotional responses, lack of emotional awareness, impulse control difficulties, difficulties engaging in goal directed behavior, lack of emotional clarity, and limited access to emotion regulation strategies.
Five-Facet Mindfulness Questionnaire
Five-Facet Mindfulness Questionnaire (FFMQ; Baer et al., 2006) is an instrument based on factor analysis of five independently developed mindfulness scales. The five factors appear to represent elements of mindfulness as it is currently conceptualized. The five facets are observing, describing, acting with awareness, non-judging of inner experience, and non-reactivity to inner experience. The FFMQ is one of the most popular scales used in study of mindfulness.
Perceived Quality of Life Measure
Perceived Quality of Life Measure (Burckhardt & Anderson, 2003) will be employed to assess general well-being. These measures will be given at baseline and every 4 weeks during treatment.
Therapist adherence and competence
Therapist adherence and competence. During the open trial all treatment sessions will be audio taped and rated by independent raters (e.g., not associated with treatment delivery) so as to assess therapist adherence to the treatment protocol. Specific therapist behaviors will be considered "prescribed" and "proscribed" (Waltz et al., 1993) in order to assure that BBMT and SC + PMR treatment are distinct. Drs. Chen and Lejuez will review 20% of the audiotapes to maintain reliability. If therapist drift from the protocol is detected, the problem will be discussed in staff meetings and corrected through supervision.
The Program Evaluation Form
he Program Evaluation Form is an 8-item self-report measure assessing participants' perceptions of and satisfaction with the treatment services.
Working Alliance Inventory (WAI)
he Working Alliance Inventory (WAI) (Horvath & Greenberg, 1989) will be used to assess therapeutic alliance. The WAI is a 36-item measure composed of items reflecting desirable aspects of the therapeutic relationship. Each item is assessed on a 7-point Likert scale ranging from 1 (never) to 7 (always), with higher scores indicating more positive therapeutic alliance.
RFB or MM Feedback and Quality Assessment
RFB or MM Feedback and Quality Assessment: BBMT participants will report daily quantity and quality of RFB or MM practice
Treatment Progress/Completion
Treatment Progress/Completion: A checklist for the therapist to document the proportion of training components being delivered and practiced by the end of week 8 facilitation.
Full Information
NCT ID
NCT02527720
First Posted
August 12, 2015
Last Updated
September 11, 2019
Sponsor
University of Maryland, College Park
1. Study Identification
Unique Protocol Identification Number
NCT02527720
Brief Title
Changing Impulsivity With Mindful Breathing Therapy to Reduce Problem Drinking
Acronym
BBMT
Official Title
Changing Impulsivity With Mindful Breathing Therapy to Reduce Problem Drinking
Study Type
Interventional
2. Study Status
Record Verification Date
September 2019
Overall Recruitment Status
Completed
Study Start Date
June 1, 2015 (Actual)
Primary Completion Date
August 1, 2016 (Actual)
Study Completion Date
December 1, 2016 (Actual)
3. Sponsor/Collaborators
Responsible Party, by Official Title
Principal Investigator
Name of the Sponsor
University of Maryland, College Park
4. Oversight
Data Monitoring Committee
No
5. Study Description
Brief Summary
The investigators plan to establish the efficacy of a novel breathing-based mindfulness training (BBMT, a much simplified, easy-to-use version of standard MM) for problem drinking, and test whether impulsivity mediates this effect among a sample of student problem drinkers (i.e., > 8 on AUDIT, the problem drinking Screening Test). The specific aims of this pilot study are as follows:
to modify and further develop the easy-to-use BBMT program for directly targeting impulsivity to produce an indirect reduction in problem drinking among college students;
to investigate the feasibility and preliminary efficacy of applying BBMT for reducing problem drinking with a pilot randomized controlled trial (RCT);
to examine changes in impulsivity, as measured by both behavioral and self-report assessments, as one of the possible mediators in the effect of BBMT on problem drinking, with control for changes in perceived stress and anxiety.
Detailed Description
An efficacious strategy for addressing problem substance use among college student drinkers is to target core risk factors. Arguably one of the most clearly documented risk factors for problem drinking among college students is impulsivity, with the relationship holding across various dimensions of impulsivity. Available evidence supports the importance of intervening with impulsivity to limit problem drinking among college students, but there are few proven treatments for any dimension of impulsivity. This notable lack may be due to the traditional view of impulsivity as an unchangeable personality trait. However, recent research suggests personality can change and is sensitive to behavior manipulation. As a result there is clear need for novel approaches targeted at core changes in the individual and their behavior patterns. Mindfulness meditation (MM) is a unique option in this direction as MM is especially useful in reducing impulsive behaviors including problem drinking, but its exact role in affecting different dimensions of impulsivity and in effecting change in problem drinking has yet to be explored. Based on evidence from recent studies, as well as our own pilot work, the investigators hypothesize that one of the mechanisms by which MM reduces problem drinking among college students is by lessening impulsivity - moreover, the focus on changing college student problem drinking is done without any explicit focus on drinking behavior itself. The specific aims of this Stage 1 therapy development study are to: 1) modify and further develop a breathing-based mindfulness therapy (BBMT) for reducing impulsivity and problem drinking among college youth; 2) investigate the feasibility and preliminary efficacy of applying BBMT for reducing problem drinking with a pilot randomized controlled trial (RCT); 3) examine changes in impulsivity, as measured by both behavioral and self-report assessments, as one of possible mediators in the observed effect of BBMT on problem drinking. These aims will be achieved in two phases. In Phase 1 the investigators will expand and fully develop the existing BBMT program with manuals to determine the effective treatment dosage for both problem drinking and impulsivity in an open label trial (n = 10). Using the modified treatment materials from Phase 1, in Phase 2 the investigators will conduct a RCT comparing the effects of modified BBMT to a Supportive Counseling + Progressive Muscle Relaxation (SC + PMR) control condition (n = 36 each) on problem drinking, assessed at baseline, weeks 4 and 8, and a 3-month follow-up. Other potential mediators such as perceived stress and anxiety also will be examined in the final model. This study has great potential implications for reaching college students drinkers less willing to acknowledge their drinking problems as it addresses a core vulnerability (impulsivity) among at-risk students in a manner that limits stigma and may reduce resistance to change. A diverse team experienced in mindfulness, impulsivity and behavior therapy development has been assembled to conduct the proposed R34 project and prepare for a full therapy development study in the future.
6. Conditions and Keywords
Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Problem Drinking
Keywords
Mindfulness, Therapy, Problem Drinking, Breathing-based mindfulness training
7. Study Design
Primary Purpose
Treatment
Study Phase
Not Applicable
Interventional Study Model
Single Group Assignment
Masking
None (Open Label)
Allocation
N/A
Enrollment
10 (Actual)
8. Arms, Groups, and Interventions
Arm Title
Mindfulness Therapy
Arm Type
Experimental
Arm Description
For the current study the investigators have developed a breathing-based, adapted for feasible application among SUD populations, and easy to carry out in clinical or non-clinical settings referred to as breathing-based mindfulness training (BBMT). BBMT is a simplified form of MM. Its core components are near resonance-frequency breathing (RFB), mindfulness training, positivity and inward attention (more details below).
Intervention Type
Behavioral
Intervention Name(s)
Mindfulness Therapy
Intervention Description
BBMT is a simplified form of MM. Its core components are near resonance-frequency breathing (RFB), mindfulness training, positivity and inward attention. A key component in BBMT is to be mindful of breathing whenever possible, and breathe at near resonance frequency (RF), known as heart rate variability biofeedback. The human cardiovascular system is known to have resonance characteristics, with the first RF at ~0.1 Hz. RF varies between 4.5 and 7 cycles per minute. Breathing at RF stimulates the cardiovascular system to oscillate at that frequency at a very high amplitude and greatly stimulates the baroreflex system. RFB is known to reduce depression and stress symptoms as well as various diseases related to malfunction of the autonomic nervous system, such as asthma and hypertension.
Primary Outcome Measure Information:
Title
Changes in substance use utilizing the Timeline Follow Back from the baseline to 3 months
Description
Timeline Follow-back (TLFB) (C. Sobell & B. Sobell, 1992) will be used to record and track participants' recent (past 30 days and 7 days) alcohol-use as well as other drug use frequency. Alcohol-use and other drug use quantity will be recorded for each day on which use was reported. The TLFB method has been shown to have good reliability and validity in college students (Sobell et al., 1989)
Time Frame
Weeks 1-8 and 3 month follow up
Secondary Outcome Measure Information:
Title
Audit
Description
Alcohol Use Diagnostic Identification Test (AUDIT) (Babor et al., 2004), has 10 items which assess frequency of drinking, typical quantity, frequency of heavy drinking, impaired control over drinking, increased salience of drinking, morning drinking, blackouts, and alcohol-related injuries within the past year. A total score of 8 or more has been found to indicate a strong likelihood of hazardous or harmful alcohol consumption
Time Frame
Baseline
Title
Readiness to Change
Description
Readiness to Change: Drug and Alcohol version of SOCRATES (Miller & Tonigan, 1996) will be used to evaluate motivation for change
Time Frame
Baseline , Week 4 , Week 8, and 3 month Follow Up
Title
Customary Drinking and Drug Use Record
Description
Customary Drinking and Drug Use Record (CDDR; Brown et al., 1998) measures lifetime alcohol use and problems to provide a baseline and examine the impact of treatment. The CDDR records age at first use and makes separate lifetime frequency use estimations for beer, wine, and distilled spirits. The CDDR has good reliability for assessing substance use behaviors among adolescents and young adults (Brown et al., 1998) and has been used specifically in college-student samples Doran et al., 2007)
Time Frame
Baseline , Week 4 , Week 8, and 3 month Follow Up
Title
Barratt Impulsiveness Scale
Description
Barratt Impulsiveness Scale (BIS-11) , includes questions focusing on motor impulsivity (acting without thinking), cognitive impulsivity (making quick cognitive decisions), and future-planning impulsivity (lack of concern about the future), with good internal consistency (alpha = 0.89 to 0.92) and test-retest reliability (0.80). Mean plus one SD in total BIS score from UM study (M = 64; SD = 17) will be used to screen and select those with high impulsivity to be included in this study to assess possible change over time.
Time Frame
Baseline , Week 4 , Week 8, and 3 month Follow Up
Title
UPPS Impulsive Behavioral Scale
Description
UPPS Impulsive Behavior scale (Whiteside & Lynam, 2001) assesses five personality pathways to impulsive behavior: negative urgency, positive urgency, (lack of) premeditation, (lack of) perseverance, and sensation seeking
Time Frame
Baseline , Week 4 , Week 8, and 3 month Follow Up
Title
Delay Discounting of Hypothetical Money Gains
Description
Delay Discounting of Hypothetical Money Gains, is a computerized binary-choice procedure. On each trial, two outcomes will be presented on the screen: one is an amount of money available immediately; the other is a larger amount of money ($50, $1,000) available after some delay (1 week, 1 year, etc.). The computerized algorithm (Holt et al., 2003) will adjust the immediate outcome for each amount/delay pairing over 6 trials to determine an indifference point, resulting in 6 indifference points (corresponding to the 6 delays) for each of 2 amounts ($50, $1,000).
Time Frame
Baseline , Week 4 , Week 8, and 3 month Follow Up
Title
Stop-Signal Task (SST)
Description
A personal computer will be used to conduct the SST, which presents two types of trials: GO and STOP. In GO trials, participants will respond with a keystroke as quickly as possible following the presentation of a visual go stimulus. In STOP trials (25% of all trials), an auditory stop signal will follow the presentation of the visual go signal. Subjects will be instructed to inhibit the go response on hearing the stop signal. The latency between onset of the go and stop signals will be titrated in the following manner: failure on a STOP trial will result in a 50ms increase in this latency, and success will result in a 50ms decrease. This method will converge on a latency, the stop signal delay (SSD) at which a participant succeeds on half of all STOP trials. After 16 GO practice trials, participants will complete five blocks of 64 trials.
Time Frame
Baseline , Week 4 , Week 8, and 3 month Follow Up
Title
Spielberger State-Trait Anxiety Inventory (STAI):
Description
both trait and state anxiety will be measured monthly to monitor changes over time
Time Frame
Baseline , Week 4 , Week 8, and 3 month Follow Up
Title
The Center for Epidemiological Studies Depression Scale (CES-D)
Description
The Center for Epidemiological Studies Depression Scale (CES-D) (Radloff, 1977) is a 20-item self-report inventory measuring mood and symptoms of depression.
Time Frame
Baseline , Week 4 , Week 8, and 3 month Follow Up
Title
Perceived Stress Scale
Description
Perceived Stress Scale is a global measure of perceived stress in daily life (Chiang et al., 2005) designed to gauge the degree to which common situations are appraised as stressful
Time Frame
Baseline , Week 4 , Week 8, and 3 month Follow Up
Title
Difficulties in Emotion Regulation Scale (DERS; Gratz & Roemer, 2004)
Description
Difficulties in Emotion Regulation Scale (DERS; Gratz & Roemer, 2004) is a well-validated 36-item, self-report questionnaire that assesses multiple aspects of emotion dysregulation. The DERS yields a total score that is comprised of scores on six subscales: nonacceptance of emotional responses, lack of emotional awareness, impulse control difficulties, difficulties engaging in goal directed behavior, lack of emotional clarity, and limited access to emotion regulation strategies.
Time Frame
Baseline , Week 4 , Week 8, and 3 month Follow Up
Title
Five-Facet Mindfulness Questionnaire
Description
Five-Facet Mindfulness Questionnaire (FFMQ; Baer et al., 2006) is an instrument based on factor analysis of five independently developed mindfulness scales. The five factors appear to represent elements of mindfulness as it is currently conceptualized. The five facets are observing, describing, acting with awareness, non-judging of inner experience, and non-reactivity to inner experience. The FFMQ is one of the most popular scales used in study of mindfulness.
Time Frame
Baseline , Week 4 , Week 8, and 3 month Follow Up
Title
Perceived Quality of Life Measure
Description
Perceived Quality of Life Measure (Burckhardt & Anderson, 2003) will be employed to assess general well-being. These measures will be given at baseline and every 4 weeks during treatment.
Time Frame
Baseline , Week 4 , Week 8, and 3 month Follow Up
Title
Therapist adherence and competence
Description
Therapist adherence and competence. During the open trial all treatment sessions will be audio taped and rated by independent raters (e.g., not associated with treatment delivery) so as to assess therapist adherence to the treatment protocol. Specific therapist behaviors will be considered "prescribed" and "proscribed" (Waltz et al., 1993) in order to assure that BBMT and SC + PMR treatment are distinct. Drs. Chen and Lejuez will review 20% of the audiotapes to maintain reliability. If therapist drift from the protocol is detected, the problem will be discussed in staff meetings and corrected through supervision.
Time Frame
Week 4, Week 8, and 3 month Follow Up
Title
The Program Evaluation Form
Description
he Program Evaluation Form is an 8-item self-report measure assessing participants' perceptions of and satisfaction with the treatment services.
Time Frame
Week 4, Week 8, and 3 month Follow Up
Title
Working Alliance Inventory (WAI)
Description
he Working Alliance Inventory (WAI) (Horvath & Greenberg, 1989) will be used to assess therapeutic alliance. The WAI is a 36-item measure composed of items reflecting desirable aspects of the therapeutic relationship. Each item is assessed on a 7-point Likert scale ranging from 1 (never) to 7 (always), with higher scores indicating more positive therapeutic alliance.
Time Frame
Week 4, Week 8
Title
RFB or MM Feedback and Quality Assessment
Description
RFB or MM Feedback and Quality Assessment: BBMT participants will report daily quantity and quality of RFB or MM practice
Time Frame
Weeks 1-8 and 3 month follow up
Title
Treatment Progress/Completion
Description
Treatment Progress/Completion: A checklist for the therapist to document the proportion of training components being delivered and practiced by the end of week 8 facilitation.
Time Frame
Week 8
10. Eligibility
Sex
All
Minimum Age & Unit of Time
18 Years
Maximum Age & Unit of Time
30 Years
Accepts Healthy Volunteers
Accepts Healthy Volunteers
Eligibility Criteria
Inclusion Criteria:
UM College Park students aged 18-30
AUDIT score of 8 or higher (Babor et al., 2004)
A total score on the Barratt Impulsiveness Scale of 73 or higher, which is the mean plus half (1/2) standard deviation, (M=64; SD=17) (Patton et al., 1995)
A commitment to adhere to the study protocol with a weekly therapy meeting (about 40 minutes each), and an extra 1.5 to 2 hours for study data collection at week 4 and week 8
No plan to move away from the UM campus area for next 2 months
Exclusion Criteria:
At current risk of suicide, including suicidal behavior or attempts in the past 30 days
A history of schizophrenia or other psychotic disorders
Current participation in other clinical studies of addiction or impulsive behavior
Severe physical and mental health problems
Overall Study Officials:
First Name & Middle Initial & Last Name & Degree
Carl Lejuez, PhD
Organizational Affiliation
University of Maryland, College Park
Official's Role
Principal Investigator
Facility Information:
Facility Name
2103 Cole Field House
City
College Park
State/Province
Maryland
ZIP/Postal Code
20742
Country
United States
12. IPD Sharing Statement
Citations:
PubMed Identifier
20649456
Citation
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Results Reference
background
Citation
Carroll, K. M., & Nuro, K. F. (2002). One size cannot fit all: A stage model for psychotherapy manual development. Clinical Psychology: Science and Practice, 9(4), 396-406.
Results Reference
background
PubMed Identifier
17333315
Citation
Karavidas MK, Lehrer PM, Vaschillo E, Vaschillo B, Marin H, Buyske S, Malinovsky I, Radvanski D, Hassett A. Preliminary results of an open label study of heart rate variability biofeedback for the treatment of major depression. Appl Psychophysiol Biofeedback. 2007 Mar;32(1):19-30. doi: 10.1007/s10484-006-9029-z. Epub 2007 Mar 1.
Results Reference
background
PubMed Identifier
10999236
Citation
Lehrer PM, Vaschillo E, Vaschillo B. Resonant frequency biofeedback training to increase cardiac variability: rationale and manual for training. Appl Psychophysiol Biofeedback. 2000 Sep;25(3):177-91. doi: 10.1023/a:1009554825745.
Results Reference
background
PubMed Identifier
11319676
Citation
Schein MH, Gavish B, Herz M, Rosner-Kahana D, Naveh P, Knishkowy B, Zlotnikov E, Ben-Zvi N, Melmed RN. Treating hypertension with a device that slows and regularises breathing: a randomised, double-blind controlled study. J Hum Hypertens. 2001 Apr;15(4):271-8. doi: 10.1038/sj.jhh.1001148.
Results Reference
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Citation
Krueger, R. A. (1994). Focus groups: A practical guide for applied research. Sage
Results Reference
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Citation
Krueger, R. A., & Casey, M. A. (2009). Focus groups: A practical guide for applied research (2 e.d.). Sage.
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Citation
Strauss, A., & Corbin, J. M. (1997). Grounded theory in practice. Sage.
Results Reference
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Changing Impulsivity With Mindful Breathing Therapy to Reduce Problem Drinking
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