Mindfulness-Based Approaches in the Treatment of Disordered Gambling

Abstract

Background and Aims:

To examine the effects of mindfulness-based interventions on gambling behavior and symptoms, urges, and financial outcomes.

Method:

Systematic review and meta-analytic procedures were employed to search, select, code, and analyze studies conducted between 1980 and 2014, assessing the effects of mindfulness-based interventions in the treatment of disordered gambling with adults.

Results:

Thirteen studies met criteria for this review and seven met criteria for meta-analysis. Effects were moderate to large for gambling behaviors/symptoms (g = 0.68, 95% CI = [0.39, 0.98], p < .01), gambling urges (g = 0.69, 95% CI = [0.18, 1.20], p < .01), and financial outcomes (g = 0.75, 95% CI = [0.24, 1.26], p < .01). Heterogeneity was low and nonsignificant.

Conclusions:

The findings provide support for mindfulness-based interventions in the treatment of disordered gambling. However, these results are necessarily tentative, limited by the number and quality of eligible studies, and differing conceptualizations of mindfulness.

Keywords

gambling mindfulness acceptance and commitment therapy addiction cognitive behavioral therapy

Gambling is a global phenomenon with expanding legalization and increased availability in a range of venues from brick and mortar establishments (e.g., casinos and race parks) to virtual forums (e.g., Internet poker and slot parlors; Ladd & Petry, 2002). While millions across the globe enjoy recreational gambling, recent prevalence reports suggest that 0.5–7.5% of a country’s population suffers from a gambling disorder, with a global average now estimated at 2.3% (Williams, Volberg, & Stevens, 2012). Gambling disorder is characterized by a range of symptoms, including preoccupation with gambling-related thoughts, chasing losses, and gambling during times of distress (American Psychiatric Association, 2013). Individuals with gambling disorder represent a heterogeneous sample (Ladouceur, Lachance, & Fournier, 2009), with varying prevalence rates across sociodemographic variables. For instance, disordered gambling prevalence rates are higher among men (Ibanez, Blanco, Moreryra, & Saiz-Ruiz, 2003), minority groups (Welte, Wieczorek, Barnes, & Tidwell, 2006), and nonimmigrant adults when compared to first-generation immigrants to the United States (Wilson, Salas-Wright, Vaughn, & Maynard, 2015). Further, disordered gambling is correlated with co-occurring disorders including psychiatric and substance use disorders (Petry, Stinson, & Grant, 2005; Welte, Barnes, Wieczzorek, Tidwell, & Parker, 2001). Only approximately 3% of disordered gamblers will eventually seek treatment, representing a very small minority (National Gambling Impact Study Commission, 1999). Further, of those that do seek treatment, 50% will drop out by the first or second session (Ladouceur et al., 2009; Ladouceur, Gosselin, Laberge, & Blaszczynski, 2001). Given the heterogeneous nature of disordered gamblers, a single, one-size fits all approach to the problem may not be appropriate for all gamblers who seek treatment (Ladouceur, 2005).

Gambling treatment options range from self-help support groups, such as gamblers anonymous (Lopez-Viets & Miller, 1997), to more individual psychotherapeutic treatment such as motivational interviewing (e.g., Hodgins, Ching, & McEwen, 2009) and cognitive behavior therapy (CBT; Okuda, Balán, Petry, Oquendo, & Blanco, 2009; Petry, 2005; Petry et al., 2006). A series of gambling treatment meta-analyses have found positive effects of psychotherapeutic interventions on gambling (Cowlishaw et al., 2012; Gooding & Tarrier, 2009; Oakley-Browne, Adams, & Mobberly, 2003; Pallesen, Mitsem, Kvale, Johnsen, & Molde, 2005). While CBT is cautiously recommended as “best practice” (Rickwood, Blaszczynksi, Delfabbro, Dowling, & Heading, 2010), current evidence in support of CBT remains tentative may be overestimated and may not work for all gamblers (Cowlishaw et al., 2012; Westphal, 2008). Moreover, evidence from alternative treatment approaches suggests potential benefits in the treatment of disordered gambling that do not fit into traditional applications of cognitive or behavioral therapies; however, few studies have adequately assessed these interventions (Gooding & Tarrier, 2009). Therefore, additional research on emerging gambling treatments is needed.

Recently, there has been increased interest in interventions that involve internalized processes including imagination, mindfulness, awareness, and attention to the present moment (hereafter referred to as mindfulness based). Emerging mindfulness-based interventions, while unique in their formal approaches to internalized stimuli and responses, all target experiential avoidance (EA). EA occurs when a person “is unwilling to experience unwanted private events (e.g., bodily sensations, thoughts, memories, urges) and takes steps to reduce the frequency or form of these events, such as disassociation, escape, and avoidance” (Riley, 2014, p. 164). EA has been conceptualized as a core mechanism in the development and course of a range of psychological disorders including gambling (Blaszczynski & Nower, 2002; Dixon & Wilson, 2014). Treatment components addressing EA focus on the function of maladaptive responding (i.e., escape and/or avoidance), rather than the form of the response, to increase adaptive responding to aversive stimuli.

For problem gamblers, escape or avoidance of aversive stimuli is often achieved and maintained through engaging in gambling behaviors. In these cases, using awareness, relaxation, and visualization techniques may assist the gambler with selecting adaptive coping behaviors. For instance, imaginal desensitization (ID) is a technique wherein gamblers are instructed to relax prior to imagining scenarios “in which they feel the urge to gamble, and to imagine exiting the scenario having refrained from gambling” (Whiting & Dixon, 2013, p. 526). These procedures are designed to assist gamblers in selecting alternative responses to aversive stimulation rather than engage in gambling. Attention and awareness to the present-moment techniques assist participants with guiding their focus on internal and external stimulation that is either appetitive or aversive (e.g., Hayes, 2004). These procedures are designed to promote attention to aversive stimuli that evoke problematic behaviors, as a means to assist gamblers in selecting alternative responses. Research to date has identified ID and present-moment awareness as treatment components that share common procedural mechanisms including active imagining during relaxation/meditation states and in vivo muscle relaxation training. Both treatment components have similar effects in brain regions involved with motivation, reward/loss processing, and executive control (Potenza et al., 2013). Similarly, intervention packages such as acceptance and commitment therapy (ACT; Dixon & Wilson, 2014; Hayes, Strosahl, & Wilson, 1999), dialectical behavior therapy (DBT; Linehan & Dimeff, 2001), mindfulness-based relapse prevention (MBRP; Bowen, Chawla, & Marlatt, 2010), and mindfulness-based cognitive therapy (MBCT; Segal, Williams, & Teasdale, 2002) that include related techniques of awareness, visualization, and present-moment focus have been found to increase positive coping strategies for urges to use (Toneatto, Vettese, & Nguyen, 2007) and tolerance of internal experience of negative cognitive and physical experiences (Bowen et al., 2009). Further, present-moment and visualization techniques have been found to increase gamblers’ awareness of structural characteristics of slot machines (e.g., wins compared to near miss or losses disguised as wins). That is, near-miss outcomes (i.e., losses that appear close to a win; see Reid, 1986) and losses disguised as wins (i.e., a win returns a smaller amount than the original bet; see Clark & Sharman, 2014) promote gambling behavior even though they are losses. Present-moment and visualization techniques may decrease gamblers’ preference over losses for these disadvantageous slot machine outcomes (Nastally & Dixon, 2012).

Mindfulness-based interventions for gambling appear to be promising, and researchers have provided theoretical and clinical implications in the treatment of gambling disorders (de Lisle, Dowling, & Allen, 2011). The extent to which these interventions are effective, however, is not known. To date, no systematic review or meta-analysis has been conducted to determine the extent to which emerging mindfulness-based interventions are effective for the treatment of disordered gambling. Therefore, the purposes of the present study were to systematically and quantitatively examine the extent to which mindfulness-based interventions are being adopted in a gambling context, to examine the various configurations of treatment components descriptively, and to examine the effects of these interventions on gambling-related outcomes. Specific questions guiding this review are (1) to what extent are mindfulness-based approaches being tested for the treatment of disordered gambling? and (2) what are the effects of mindfulness-based approaches on gambling outcomes (i.e., gambling behavior, urges, and financial outcomes) with adult problematic or pathological gamblers compared to other treatment or no treatment?

Method

Systematic review procedures (Campbell Collaboration, 2014) were used to search, select, and code studies eligible for the review. Meta-analytic methods were used to synthesize outcomes reported in studies that met inclusion criteria for the meta-analysis. The review protocol, developed a priori, is registered with PROSPERO (Registration #CRD42014010748; Maynard et al., 2014).

Study Eligibility Criteria

Studies conducted between January 1980 and April 2014 assessing the effects of a mindfulness-based intervention with adult participants identified as problematic or pathological gamblers were eligible for this review. Studies must have used a randomized, quasi-experimental, single-group pre–posttest (SGPP) or single-subject experimental design to be included in the review. To be included in the meta-analysis, studies must have used a randomized or quasi-experimental study design assessing effects of a mindfulness-based intervention against a comparison group that did not receive mindfulness-based interventions. For the purposes of this study, mindfulness-based interventions included methods where participants were encouraged to focus their attention either on covert activity (e.g., thoughts, feelings, and urges) or on overt activity (e.g., lights, sounds, and smells) as a primary or adjunctive intervention. Mindfulness-based interventions included present-moment work, meditation, relaxation skills (including muscle relaxation procedures), breathing techniques, and awareness of moment techniques delivered in vivo, via formal meditation practices or informal mindfulness exercises, mindfulness-based stress reduction (MBSR), MBCT, DBT, ACT, and ID. ID was included given similarities to mindfulness-based procedures (e.g., visualizing exposure to gambling-related activities, muscle relaxation, and present-moment focus on in vivo experiences of gambling activities). To be eligible for the review, studies must have assessed the effects on any outcome. For inclusion in the meta-analysis, studies must have measured at least one of the following outcomes: gambling behavior or symptoms, gambling urges, or a gambling-related financial outcome.

Study Search, Selection, and Coding Procedures

A comprehensive and systematic search strategy was conducted in an attempt to identify and retrieve all relevant published and unpublished studies meeting inclusion criteria. The search, completed in April 2014, involved several sources. Information sources included the following 13 electronic databases and research registries: Academic Search Complete, ProQuest Dissertations & Theses, MEDLINE, National Criminal Justice Reference Service (NCJRS), PsycINFO, SCOPUS, Social Science Citation Index, Social Services Abstracts, Social Work Abstracts, Campbell Collaboration Library, Cochrane Collaboration Library, ClinicalTrials.gov, and OpenGrey. We used combinations of the following terms and key words related to the problem, outcome, intervention, and target population (see online supplementary material for details of the database search strategies): gambl* AND (mindfulness OR meditation OR awareness OR acceptance OR relaxation OR “dialectical behavior therapy” OR “present moment”) AND (evaluation OR intervention OR treatment OR outcome OR program). Additional efforts were employed to find unpublished, or “gray,” literature, which included contacting first authors of published studies and other researchers working in the area of gambling interventions.

All titles and abstracts retrieved through the search strategy were screened for relevance by one reviewer. The full text of all studies that were not obviously ineligible or were questionable at this stage was obtained and independently screened for eligibility by two reviewers using a screening instrument. Reviewers resolved discrepancies in screening decisions through discussion and consensus and, when necessary, a third reviewer was consulted. Two reviewers then independently coded all reports that passed eligibility screening using a coding instrument to guide systematic examination and extraction of data. Two reviewers pilot tested the coding instrument with two studies and made adjustments to the coding form. After finalization of the coding instrument, two reviewers independently coded the remainder of the studies. The coding instrument included categories concerning all relevant bibliographic information; study context, intervention, and sample descriptors; research methods and design; and effect size data (coding instrument may be obtained from the authors). Risk of bias was assessed for all studies included in the meta-analysis by two independent coders using the Cochrane Collaboration’s risk of bias tool (Higgins & Thompson, 2002). Agreement between the two reviewers was 96%. Disagreements were resolved by discussion and consensus and, when necessary, a third reviewer was consulted.

Statistical Methods

Several statistical procedures were conducted following recommendations of Pigott (2012). First, statistical analysis was designed to produce descriptive information on the characteristics of all included studies. Effect sizes were then calculated on reported outcomes from the seven studies that met criteria to be included in the meta-analysis. The standard mean difference effect size statistic, corrected for small sample size bias (Hedges’ g), was calculated using a statistical software package, Comprehensive Meta-Analysis Version 2.0 (CMA; Borenstein, Hedges, Higgins, & Rothstein, 2005). For the three studies that measured outcomes using categorical variables, data were entered into CMA and converted to Hedges’ g. Meta-analysis, assuming random effects models using inverse variance weights, was used to quantitatively synthesize results across the included studies. To ensure the independence of study-level effect sizes, we included only one effect size per study per outcome construct. When authors used multiple reports of the same outcome measure (e.g., self and clinician reports) or multiple measures of the same outcome (e.g., two different instruments measuring gambling behavior), we calculated the mean of all measures to create a study-level average across measures. One study (Blaszczynski, Maccallum, & Joukhador, 2001) used three groups, and we selected the ID group as the treatment group and the cognitive therapy group as the comparison group for the meta-analysis. Of note, we chose to conduct separate meta-analyses for each of the three outcomes of interest in this review, gambling behaviors and symptoms, gambling urges, and financial outcomes, given their divergent latent nature. One study included in the meta-analysis of gambling behaviors and symptoms and one study in the meta-analysis of gambling urges used a wait-list control group, while all other studies used an active treatment control group. We conducted a sensitivity analysis to examine whether combining studies with an active versus wait-list control group in the meta-analyses impacted the effect size estimate. We found no significant differences in the magnitude of effect between the studies with an active treatment control group versus a wait-list control group and thus elected to combine them in the meta-analysis.

To examine whether between-study variability is greater than what we would expect from sampling error alone, an analysis of heterogeneity was conducted. We calculated Cochrane’s Q, a commonly used significance test of heterogeneity, as well as I ², which indicates how heterogenous the effect sizes are (where zero represents homogeneity; Card, 2012; Higgins & Thompson, 2002). The I ² index is a ratio, put into a percentage, of the between-study variability relative to the total variability and represents the amount of heterogeneity among studies in the meta-analysis. (Card, 2012). A moderate to large amount of heterogeneity, enough to warrant moderator analyses, is between 50% and 100%. We had planned to conduct moderator analyses (type of gambler, whether mindfulness was primary mechanisms, length of treatment, and treatment format), but given the homogeneity across studies on all outcomes, moderator analyses were not indicated (Lipsey & Wilson, 2001). We also planned to assess and report publication bias by constructing a scatter plot of study effect size by sample size; however, the use of funnel plots or other techniques such as regression to assess publication bias with fewer than 10 studies is not indicated (Card, 2012).

Results

The search procedures yielded 3,331 titles from the electronic databases. After review of titles and abstracts from databases in addition to the review of reference lists from 84 prior reviews and primary studies, 39 reports were retrieved in full text for screening. Of those reports, 22 reports were excluded (see online Supplemental Materials), for a full list of excluded studies as they did not meet basic eligibility criteria (e.g., not an intervention study, not a study of problematic or pathological gamblers, and not a mindfulness-based intervention). The final sample for this review included 13 studies reported in 17 articles. Seven of the included studies, all randomized controlled trials, were eligible for the meta-analysis (see Table 1). The remaining six studies (see Table 2) were excluded from the meta-analysis due to not meeting criteria related to study design (n = 5) or did not measure outcomes relevant to this review (n = 1). See Figure 1 for a flow diagram of the search and selection process.

Table 1.

Summary of Studies Included in Meta-Analyses.

First Author (Year)	Treatment	Intervention Description	Males (%)	Gambler-Type Comorbidity (If Reported)	N	Control	Outcomes
Blaszczynski (2005)	ID	Two treatment sessions over 1 week. Homework: participants directed to listen to the audiocassette tape containing two ID sessions and practice the technique 3 times a day for 5 consecutive days	65	Pathological	68	Group CT	Posttest measured at 1 month. Gambling behavior: Assessed as being abstinent, controlled, (we coded as successful), and one-two episodes or uncontrolled (we coded as unsuccessful) Other: Clinical ratings of change in gambling, self-report cognitive beliefs
Dowling (2006)	CBT with ID	Twelve, 90-min sessions ideally over 12 weeks (mean = 22 weeks); primarily CBT approach; during final 20 min of first six sessions, participants participated in ID in the manner outlined by McConaghy, Armstrong, Blaszczynski, and Allcock (1983, 1988)—participants were required to maintain a state of relaxation while visualizing themselves performing behaviors in scenes in which they were stimulated to gamble but in which they left without gambling. Homework: exercises assigned between sessions but did not specify whether homework involved mindfulness practice/exercises	0	Pathological	19	WLC	Posttest measured following treatment; self-reported gambling diary records Gambling behavior: Frequency and duration Financial: Money inserted and expenditure Other: Depression, anxiety, self-esteem
Grant (2009)	ID with MI	Six, 60-min sessions over 8 weeks. Session 4 introduced ID by creating and audiotaping three gambling scenarios that stimulated gambling urges. Relaxation training and cognitive skills were used to cope with the urges that the scenarios elicited. Homework: participants were instructed to listen to the tape 3 times each day	37	Pathological: alcohol/drug (6%), psychiatric (65%), nicotine (40%)	68	GA	Posttest measured 1 week after final session; evaluation performed by raters blind to condition Gambling symptoms: PG-YBOCS Behavior subscale; G-SAS Gambling urges: PG-YBOCS urge/thought subscale Other: Global functioning, depression, anxiety, disability, and quality of life
Korman (2008)	Modified DBT	Fourteen, 60-min sessions over 14 weeks; modified DBT approach; Homework: none assigned	86	Problematic: substance dependence or abuse (43%), problem anger (100%)	42	TAU	Posttest measured at end of treatment; self-report Gambling symptoms: PGSI Financial: Monthly income percentage spent on gambling Other: Substance use, anger, and therapeutic alliance
McConaghy (1983)	ID	Fourteen, 15-min sessions over a 1 week admission to a psychiatric unit; each participant provided four scenes in which they were stimulated to gamble and trained in a relaxation procedure to use when visualizing each of the four scenes. Homework: none reported	80	Pathological	20	Aversive therapy	Measured at 1 month following commencement of treatment; author assessed Gambling behavior: Absent, controlled (we coded as successful) and markedly reduced, slightly reduced, or unchanged (we coded as unsuccessful) Gambling urges: Absent (we recoded as successful) and markedly reduced, slightly reduced, or unchanged (we recoded as unsuccessful) Other: Anxiety
McConaghy (1988)	ID	Fourteen sessions over 1 week’s admission to a psychiatric unit; Participants were first briefly trained to relax their muscles. While remaining relaxed, they visualized being in situations that led to gambling or in which they had gambled in the past, but they visualized not completing the gambling behavior. Homework: none assigned	95	Pathological	20	Imaginal relaxation	Posttest measured at 1 month following commencement of treatment; author assessed Gambling behavior: Absent, controlled (we recoded as successful) and markedly reduced, slightly reduced, or unchanged (we recoded as unsuccessful) Gambling urges: Absent (we coded as successful) and markedly reduced, slightly reduced, or unchanged (we coded as unsuccessful) Other: Anxiety
Toneatto (2014)	Mindfulness-enhanced CBT	Five, 60-min sessions over 7 weeks; each session consisted of 45 min. CBT + 15 min. CD-guided mindfulness instruction; homework: participants asked to practice mindfulness 30 min/day at home	36	Pathological	18	WLC	Posttest measured 2 weeks following last treatment session; self-reported outcomes Gambling urges: Number of urges reported Other: DSM symptoms, emotional distress, and trait mindfulness

Note: All included studies in the meta-analysis were randomized controlled trials. Intervention and control conditions: ID = imaginal desensitization; CBT = cognitive behavioral therapy; CT = cognitive therapy; DBT = dialectical behavior therapy; WLC = wait-list control; MI = motivational interviewing; TAU = treatment as usual; Measures: PG-YBOCS = Yal–Brown Obsessive Compulsive Scale Modified for Pathological Gambling; G-SAS = Gambling Symptom Assessment Scale; PGSI = Problem Gambling Severity Index. Other outcomes were not included in the meta-analyses but are noted.

Table 2.

Summary of Included Studies That Did Not Meet Criteria for Inclusion in Meta-Analysis.

First Author (Year)	Intervention	Intervention Description	Study Design	Males (%)	Gambler-Type Comorbidity (If Reported)	n	Outcomes	Author Reported Results
Blaszczynski (2005)	Imaginal desensitization	One session in which each participant was given a copy of a 40-min prerecorded audiocassette, containing two 20-min ID sessions and printed instructions. Homework: participants were directed to listen to the audiocassette and practice the technique 3 times/day for 5 days	SGPP	77	Pathological	79	Gambling: Hours gambled per week, urge, and preoccupation with gambling Financial: Amount of money Other: Impulsivity, depression, and anxiety	Pretest to posttest within group change (significant attrition analytic n = 47): “Results … support the findings of earlier studies that imaginal desensitization leads to a positive outcome in a substantive proportion of pathological gamblers who present for treatment”
Christensen (2013)	Brief DBT	Nine, 2.5-hr DBT skills sessions over 9 weeks. Homework: assigned a home practice in relation to the learned skill	SGPP	21	Problematic: treatment resistant, BPD: 50%	24	Gambling: Self-report time spent gambling Financial: Amount spent on gambling, amount lost Other: Psychological distress, mindfulness, distress tolerance, emotion dysregulation, negative relationships, alcohol and drug use, and client satisfaction	Pretest to posttest within group change (significant attrition analytic n = 12–14): Not significant: gambling sessions and expenditure, negative relationships Significant: Psychological distress, distress tolerance, and emotion dysregulation
de Lisle (2011)	MBCT for problem gambling	Adapted from manualized MBCT; Eight weekly 2-hr individual sessions and two follow-up sessions. Homework: mindfulness practice 40 min/day	SSD A-B-A	0	Problematic	1	Gambling: SCIP, GSEQ, and gambling frequency and duration Financial: Expenditure Other: Anxiety, depression, mindfulness (five facets), and client satisfaction	Reduced gambling frequency, duration, and expenditure; improved psychological functioning; moderate improvement in observing, nonjudging and nonreactivity mindfulness, and no improvement in describing and acting with awareness
Nastally (2010)	Brief ACT intervention	One 90-min session; Homework: none assigned	SSD A-B MB	67	Pathological and problematic	3	Gambling: subjective closeness to win ratings and total time played during the free play phase	“Visual analysis indicates robust effectiveness of the intervention for [2 participants] and although not as pronounced, there was a general downward trend in [the third participant’s] data”
Sharma (2009)	Psychotherapy and Vipassana meditation	Daily group meditation for 60 min under the supervision of yoga experts, psychotherapy—45 sessions over 6 months; Homework: none assigned	QED	NR	Pathological	100	Gambling: none Other: TAT	“The present study has shown that the characteristics associated with treated pathological gamblers are grammatically correct language, superior organization capacity, dominance, autonomy, achievement, counteraction, sex, guilt, dejection, cordial affectionate relations and happiness whereas characteristics associated with nontreated gamblers are emotional tone, aggression, passivity, anxiety, inferiority and press”
Shonin (2014)	CBT and meditation awareness training (MAT)	Twenty weekly session (50 or 90 min depending on week) divided into two stages: (1) weeks 1–10: employed second-wave CBT principles and (2) weeks 11–20: utilized a meditation-based recovery model Homework: received a program booklet and a guided meditation CD to encourage meditation practice in daily routine	SSD A-B-C	0	Pathological: schizophrenia	1	Gambling: DSM diagnostic criteria, G-SAS, and gambling frequency and duration Financial: Gambling spend Other: psychiatric symptoms, GAF, MAAS, and GAS	Clinically significant change in schizophrenia and pathological gambling symptomatology, significant baseline-to-end point improvements in all outcome variables; improvements maintained at follow up

Note. Study design: SGPP = single-group pre–posttest design; QED = quasi-experimental design; SSD = single-subject design; MB = multiple baseline across participants; CS = case study; outcomes reported: SCIP = structured clinical interview for pathological gambling; GSEQ = gambling self-efficacy questionnaire; TAT = thematic apperception test; G-SAS = Gambling Symptom Assessment Scale; GAF = Global Assessment of Functioning Scale; MAAS = Mindfulness Attention and Awareness Scale; GAS = Goal Attainment Scale; BPD = bipolar disorder; DSM = Diagnostic and Statistical Manual; GA = gamblers anonymous; MBCT = mindfulness-based cognitive therapy; NR = not reported; DBT = dialectical behavior therapy.

Figure 1.

Study selection flowchart. ¹A table of excluded studies with reasons for exclusion is available in online Supplemental Materials.

Characteristics of Included Studies

Study characteristics

Table 3 summarizes study and participant characteristics across included studies. Of the 13 studies included in this review, seven were randomized controlled trials (RCTs), one was a quasi-experimental design (QED) study, two were SGPP studies, and three were single-subject design studies. The included studies were conducted across a broad range of geographical areas, with the largest proportion (53%) being conducted in Australia. Despite attempts to search for unpublished studies, the majority (92%) of the included studies were published in peer-reviewed journals, with one study published as a conference proceeding. Most of the studies employed small sample sizes, with most studies (61%) employing samples of less than 25 participants and no study included over 100 participants. Of the studies included in the meta-analysis, all studies reported posttest outcomes and several studies conducted follow-up analysis, ranging from 3 months to 1-year posttreatment; however, only three of the seven RCTs reported follow-up results for both treatment and comparison groups (Korman et al., 2008; McConaghy, Armstrong, Blaszczynski, & Allcock, 1983, 1988).

Table 3.

Study and Sample Characteristics Across Included Studies.

	All Studies (n = 13)	Included in MA (n = 7)	Not Included in MA (n = 6)
Characteristic	n (%)	n (%)	n (%)
Study design
RCT	7 (53)	7 (100)	0 (0)
QED	1 (7)	0 (0)	1 (16)
SGPP	2 (15)	0 (0)	2 (33)
SSD	3 (23)	0 (0)	3 (50)
Publication status
Published	12 (92)	6 (86)	6 (100)
Not published	1 (6)	1 (14)	0 (0)
Sample size
1–25	8 (61)	4 (57)	4 (66)
26–75	3 (23)	3 (43)	0 (0)
76–100	2 (15)	0 (0)	2 (33)
100+	0 (0)	0 (0)	0 (0)
Country
United States	2 (15)	1 (14)	1 (16)
United Kingdom	0 (0)	0 (0)	0 (0)
Canada	2 (15)	2 (29)	0 (0)
Australia	7 (53)	4 (57)	3 (50)
Other	1 (7)	0 (0)	1 (16)
Not reported	1 (7)	0 (0)	1 (16)
Setting
Outpatient clinic	8 (61)	5 (71)	3 (50)
Inpatient	2 (15)	2 (29)	0 (0)
Other	2 (15)	0 (0)	2 (33)
Not reported	1 (7)	0 (0)	1 (16)
Predominant race
Caucasian	2 (15)	1 (14)	1 (16)
African American	1 (7)	0 (0)	1 (16)
Hispanic	0 (0)	0 (0)	0 (0)
Other	0 (0)	0 (0)	0 (0)
Not reported	10 (76)	6 (86)	4 (66)
Type of gambler
Pathological	9 (69)	6 (86)	3 (50)
Problematic	3 (23)	1 (14)	2 (33)
Both	1 (7)	0 (0)	1 (16)
Comorbid conditions^a
Substance use	2 (15)	2 (29)	0 (0)
Anger/aggression	1 (7)	1 (14)	0 (0)
Mental health	3 (23)	1 (14)	2 (33)
Personality disorder	1 (7)	0 (0)	1 (16)
Not reported	8 (61)	5 (71)	3 (50)

Note. MA = meta-analysis; RCT = randomized controlled trial; QED = quasi-experimental design; SGPP = single-group pre–posttest; SSD = single-subject design.

^aCategories not mutually exclusive.

Participant characteristics

Across the 13 studies, participants included a total of 463 gamblers. Most studies included either pathological gamblers (69%) or problematic gamblers (23%), with only one study including both pathological and problem gamblers. A larger proportion of RCT studies included in the meta-analyses (86%) included pathological gamblers compared to other study designs (50%). Most studies included both male and female participants; however, three studies (23%) included only female participants and two studies (15%) included only male participants. Most studies (76%) did not provide enough information to code race and ethnicity. For the three that did report race or ethnicity, two studies included predominantly Caucasian participants and one included predominantly African American participants.

Intervention characteristics

Table 4 summarizes the characteristics of interventions across the included 13 studies. All studies must have employed a mindfulness component to be included in this review; however, there was variability across studies on intervention characteristics. The mindfulness-based component of the intervention was the primary mechanism of interest in most of the studies (69%). Several studies employed interventions in addition to mindfulness, such as behavioral interventions (7%), cognitive interventions (31%), and other types of counseling interventions (23%). A large proportion of the total studies (46%) and majority of studies included in the meta-analysis (71%) used ID as either the primary or adjunctive intervention. Other interventions tested were DBT (n = 2), MBCT, (n = 1), mindfulness-enhanced CBT (n = 1), and ACT (n = 1). Mindfulness practice was assigned as homework in about half (53%) of the studies. Most studies (76%) delivered the intervention in an individual format, but one study used a group format and one study used both individual and group formats. Interventions varied in terms of the number of sessions (range, 1–20) and length of treatment (range, 1–24 weeks). Of the 12 studies that reported number of sessions and treatment duration, most (75%) were shorter term interventions of less than 12 weeks or 12 sessions. About half of the primary study authors reported the use of an intervention manual and most (84%) monitored fidelity of the intervention; however, only two studies measured and reported treatment fidelity.

Table 4.

Intervention Characteristics Across Included Studies.

	All Studies (n = 13)	Included in MA (n = 7)	Not Included in MA (n = 6)
Characteristic	n (%)	n (%)	n (%)
Type of mindfulness intervention
Imaginal desensitization	6 (46)	5 (71)	1 (16)
Dialectical behavior therapy	2 (15)	1 (14)	1 (10)
Mindfulness-based stress reduction	0 (0)	0 (0)	0 (0)
Mindfulness-based cognitive therapy	1 (7)	0 (0)	1 (10)
Mindfulness-enhanced CBT	1 (7)	1 (14)	0 (0)
Acceptance and commitment therapy	1 (7)	0 (0)	1 (16)
Other	2 (15)	0 (0)	2 (33)
Mindfulness homework assigned?
Yes	7 (53)	3 (43)	4 (66)
No	6 (46)	4 (57)	2 (33)
Mindfulness primary intervention
Yes	9 (69)	4 (57)	5 (83)
No	4 (30)	3 (43)	1 (16)
Additional, nonmindfulness strategies used^a
None	5 (31)	3 (43)	2 (33)
Behavioral strategies	1 (7)	1 (14)	0 (0)
Cognitive strategies	5 (31)	3 (43)	2 (33)
Other counseling/talk therapy	3 (23)	1 (14)	2 (33)
Other	0 (0)	0 (0)	0 (0)
Treatment format
Individual	10 (76)	6 (86)	4 (66)
Group	1 (7)	1 (14)	0 (0)
Individual and group	1 (7)	0 (0)	1 (16)
Unable to determine	1 (7)	0 (0)	1 (16)
Manualized program?
Yes	9 (69)	5 (71)	4 (66)
No	2 (15)	1 (14)	1 (16)
Unable to determine	2 (15)	1 (14)	1 (16)
Fidelity
Measured	2 (15)	2 (29)	0 (0)
Monitored but not measured	11 (84)	5 (71)	6 (100)
Not monitored or measured	0 (0)	0 (0)	0 (0)

Note. MA = meta-analysis.

^aCategories not mutually exclusive.

Risk of Bias

Risk of bias was assessed for all studies included in the meta-analyses. Overall, there was moderate risk of bias within and across the included studies (see Table 5). Selection bias, assessed on random sequence generation and allocation concealment, was assessed as unclear in the majority of studies, as the study authors stated they randomized participants to condition but did not report sufficient information regarding randomization procedures. In terms of performance bias, all studies were rated as high risk, as they did not report blinding participants to condition. Most of the studies (57%) were rated as high risk of bias for detection bias, as only three studies reported blinding of outcome assessors. Attrition bias and reporting bias were assessed as low risk across most of the studies, with only one study assessed as high risk of bias for attrition bias and one study assessed as high risk of bias for reporting bias.

Table 5.

Risk of Bias Summary Table: Review Authors’ Judgments About Each Risk of Bias for Each Included Study.

First Author (Year)	Selection Bias (Randomization)	Selection Bias (Allocation)	Performance Bias	Detection Bias	Attrition Bias	Reporting Bias
Blaszczynski (2005)	U	U	H	H	H	L
Dowling (2006)	U	U	H	H	U	L
Grant (2009)	L	U	H	L	L	L
Korman (2008)	U	U	H	H	L	L
McConaghy (1983)	U	U	H	L	L	L
McConaghy (1988)	U	U	H	L	L	L
Toneatto (2014)	H	H	H	H	U	H
Percentage assessed as low risk	14	0	0	42	57	85

Note. Toneatto—reporting bias—did not report gambling behavior that one would expect to report. H = high risk of bias; L = low risk of bias; U = unclear risk of bias.

Effects of Interventions

Meta-analysis was conducted for each of the three outcomes included in this review for the seven intervention studies that met criteria to be included in the meta-analysis.

Gambling behavior and symptoms

Mean effects and confidence intervals (CIs) for the six studies that measured gambling behaviors and/or symptoms (Blaszczynski et al., 2001; Dowling, Smith, & Thomas, 2006; Grant et al., 2009; Korman et al., 2008; McConaghy et al., 1983, 1988) are shown in Figure 2. The results indicate a positive, moderate, and statistically significant treatment effect (g = 0.68, 95% CI = [0.39, 0.98], p < .01). Heterogeneity was low (I ² = 0%) and not statistically significant (Q = 4.21, p = .42). This effect represents a difference of approximately 40% in frequency and 48% in duration of gambling behavior and, on the Problem Gambling Severity Index, would represent the difference between scoring moderate risk versus high risk for gambling severity.

Figure 2.

Effects of mindfulness-based interventions on gambling behaviors/symptoms. *p < .01.

Gambling urges

Mean effects and CIs for the four studies that reported outcomes related to gambling urges (Grant et al., 2009; McConaghy et al., 1983, 1988; Toneatto, Pillai, & Courtice, 2014) are shown in Figure 3. The results indicate a positive, moderate, and statistically significant treatment effect (g = 0.69, 95% CI = [0.18, 1.20], p = .01). Heterogeneity was low (I ² = 33.44%) and not statistically significant (Q = 4.51, p = .21). This effect represents a difference in the number of gambling urges of approximately 31%.

Figure 3.

Effects of mindfulness-based interventions on gambling urges. *p < .01.

Financial outcomes

Mean effects and CIs for the two studies that reported outcomes related to financial outcomes are shown in Figure 4. The results of the synthesis indicate a positive, large, and statistically significant treatment effect (g = 0.75, 95% CI = [0.24, 1.26], p < .01). Heterogeneity was low (I ² = 0%) and not statistically significant (Q = 0.65, p = .52). This effect represents a difference in expenditure between control and intervention groups of approximately 87%.

Figure 4.

Effects of mindfulness-based interventions versus control on financial outcomes. *p < .01.

Discussion and Application to Practice

Despite the emerging evidence of mindfulness-based interventions for a growing number of health and behavioral health conditions (Chiesa & Serretti, 2014; de Vibe, Bjorndal, Tipton, Hammerstrom, & Kowalski, 2012; Ost, 2008; Swain, Hancock, Hainsworth, & Bowman, 2013; Zgierska et al., 2009), little is known about the effects of mindfulness-based interventions for gambling. Given the increased popularity of mindfulness-based interventions across a range of problems, and particularly for gambling, we believe it is important to examine the current state of research of mindfulness-based interventions on gambling to inform practice and future research in this area. In terms of practice, it is important that practitioners are aware, despite the popularity of mindfulness-based interventions, of the empirical evidence of this novel intervention, so practitioners can make informed decisions. In terms of research, synthesizing an emerging body of research provides evidence of gaps and limitations in the current evidence base that researchers can use to build upon and advance research in this area to better inform practice. Moreover, quantitatively synthesizing two or more studies provides additional information than what can be revealed in individual studies and allows for more valid conclusion than other techniques such as narrative synthesis or vote counting (Valentine, Pigott, & Rothstein, 2010). Therefore, this study provides an important first step toward understanding the utility and effectiveness of emerging mindfulness-based treatments for disordered gambling.

The present review included 13 studies, of which 7 assessed effects using a comparison group design and met criteria to be included in the meta-analysis. Overall, mindfulness-based interventions demonstrated positive and significant effects on gambling behavior and symptoms, gambling urges, and financial outcomes. Thus, the present findings provide tentative support for the utility of mindfulness-based interventions in the treatment of disordered gambling. Studies that met criteria for this review used various strategies, six used ID (46%) and five (38%) tested effects of a “named” intervention (i.e., DBT, MBSR, MBCT, and ACT). It is important to note that when study findings were examined individually, effects of several interventions were not significantly different from zero. When combined, however, the pooled effect size was significant. Given the small sample sizes within each study, it is possible that primary studies failed to demonstrate significant effects because they were underpowered. One of the strengths of meta-analysis over narrative or vote-counting methods is the capability to find effects that are not readily apparent or are obscured when using less sophisticated approaches (Lipsey & Wilson, 2001). By pooling effects across studies, meta-analysis can combine the results of underpowered studies, producing a synthesized effect estimate with considerably more statistical power to discover meaningful effects that can be missed in low-powered individual studies (Card, 2012).

Current findings are generally consistent with prior reviews of mindfulness-based interventions with other problems and support the notion that mindfulness-based interventions are promising or effective for a range of mental and behavioral health conditions, including anxiety (Arch, Eifert, Davies, & Vilardaga, 2012) and substance use disorders (Powers, Zum Vorde Sive Vording, & Emmelkamp, 2009; Zgierska et al., 2009). For example, a recent systematic review comparing ACT to CBT found ACT outperformed CBT across a range of symptoms (Ruiz, 2012). Similarly, a meta-analysis of laboratory-based studies of mindfulness components found significant effects, particularly for those that included experiential processes (Levin, Hildebrandt, Lillis, & Hayes, 2012). Implications of these analyses support the significance of the underlying mechanisms within mindfulness-based interventions, particularly the impact of experiential processes and mindfulness meditation practices.

Components of mindfulness, including nonreactivity to inner experiences, acting with awareness, and observing inner experiences (e.g., thoughts, feelings, urges, etc.), have been identified as predictors of psychological symptoms (Baer, Smith, Hopkins, Krietemeyer, & Toney, 2006) and gambling proclivity (Lakey, Campbell, Brown, & Goodie, 2007). Each of these operative components, which together constitute the multifaceted construct of mindfulness, has been delivered in a variety of procedures, and the contribution of each component differs based on the arrangement of the task (Baer et al., 2006). For example, within the present analysis, several studies implemented ID including imagery of abstaining from gambling within a problematic context (e.g., Dowling, et al., 2006; McConaghy et al., 1983, 1988). The instructions and exercises featured awareness of urges and imagining with this awareness as central components, but the acceptance or nonreactivity component was less prevalent. In contrast, practice mindfulness exercises such as those utilized by Toneatto, Pillai, and Courtice (2014) specifically target all three components. For disordered gamblers, effective mindfulness-based interventions target problematic EA by assisting with awareness of inner experiences (including gambling-related triggers and urges to use), and focusing activity to both covert and overt experiences from a nonjudgmental and nonreactive position. Each component of mindfulness represents part of the effort toward this end, and as suggested by the results of the present meta-analysis, different arrangements and presentations of these components may be effective in combating disordered gambling as they relate to covert (e.g., gambling-related urges; Toneatto et al., 2014) and overt experiences (e.g., gambling behaviors and financial outcomes; Dowling et al., 2006). However, definitional issues related to mindfulness-based interventions limit the extent to which researchers have identified and tested key mechanisms of change across these interventions. Therefore, future research should conduct component analyses to determine specific mechanisms of change in mindfulness-based interventions that result in robust behavioral change.

Overall, the current review provides tentative support for mindfulness-based interventions in the treatment of disordered gambling; however, it is clear that additional research is needed. Consistent with findings from prior reviews of other interventions for gambling, primary studies included in this review suffer from methodological shortcomings and small sample sizes. Future studies should employ more rigorous study designs and larger samples. Independent replication studies are also needed as are studies assessing comparative effects of interventions, particularly against CBT, which is currently considered best practice. Future research should also consider longer term effects of interventions, as the current evidence base is sorely lacking evidence of long-term effectiveness. In addition, while examining effects of interventions is important, other aspects of interventions, such as implementation, acceptability, and cost-effectiveness, are important to consider when selecting interventions and should be measured and reported in future studies to better inform treatment decisions.

Limitations

The conduct and reporting of this review was guided by standards and policies for the conduct and reporting of systematic reviews to ensure a rigorous and transparent review designed to minimize bias and error. This review is not without its limitations, however, and the findings must be interpreted in light of the study’s limitations. We conducted a comprehensive search, including a search for gray literature; however, we discovered only one unpublished study and our sample size was too small to conduct meaningful publication bias analyses, thus publication bias is a potential threat to the validity of this review. Despite the inclusion of only randomized trials in the meta-analysis, the included studies presented with various risks of bias and thus caution must be used when drawing causal conclusions and applying findings from this review. Also, due to the nascent use of mindfulness-based interventions, particularly for gambling, our review includes a relatively small number of studies, which restricted our ability to conduct more sophisticated analyses and limits the generalizability of our findings. Moreover, we were unable to examine the differential effects of different types of mindfulness interventions. While the lack of heterogeneity across studies indicates that effects of interventions are similar, we likely did not have sufficient statistical power to detect heterogeneity and, due to the small number of studies, moderator analyses would have been underpowered. It also should be noted that this review is limited to adults, and none of the studies included participants of Asian background. Therefore, additional research is needed on both of these populations who are at high risk of developing gambling problems. Lastly, there is disagreement about what constitutes a mindfulness-based intervention and thus different authors may have made different inclusion decisions; however, we were transparent in our definition and inclusion criteria and thus other authors may choose to conduct a different synthesis using a different framework. Despite these limitations, the present study provides the first systematic synthesis of mindfulness-based interventions for problematic and pathological gambling and elucidates the promise of these types of interventions and the gaps in the evidence in this area to inform future research.

Conclusion

Our findings revealed promising preliminary evidence for use of mindfulness-based approaches in the treatment of gambling disorders, but conclusive evidence is lacking. The current evidence base is small and the methodological limitations found in the corpus of studies limit the conclusions that can be drawn from this review. Nevertheless, the findings of the current review confirm that approaches that include imaginal, attention focusing, awareness, and mindfulness may be effective in reducing gambling behaviors and symptoms, urges, and financial losses. Findings also demonstrate the need for further development and more rigorous evaluation of the effects of these emerging approaches in the treatment of gambling disorders.

Footnotes

Declaration of Conflicting Interests

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The authors received no financial support for the research, authorship, and/or publication of this article.

Supplemental Material

Supplementary material for this article is available online.

References

American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders: DSM 5. Arlington, TX: American Psychiatric Publishing.

Arch

J. J.

Eifert

G. H.

Davies

Vilardaga

J. C.

(2012). Randomized clinical trial of cognitive behavioral therapy versus acceptance and commitment therapy for mixed anxiety disorders. Journal of Consulting and Clinical Psychology, 80, 750–765.

Baer

R. A.

Smith

G. T.

Hopkins

Krietemeyer

Toney

(2006). Using self-report assessment methods to explore facets of mindfulness. Assessment, 13, 27–45.

Blaszczynski

Drobny

Steel

(2005). Home-based imaginal desensitisation in pathological gambling: Short-term outcomes. Behaviour Change, 22, 13–21.

*Blaszczynski

Maccallum

Joukhador

(2001). A comparative evaluation of imaginal desensitisation and group cognitive therapy in the treatment of pathological gambling. In Coman

(Ed.), Lessons of the past: Proceedings of the 10th conference of the National Association for Gambling Studies (pp. 40–49). Victoria, Australia: National Association for Gambling Studies.

Blaszczynski

Nower

(2002). A pathways model of problem and pathological gambling. Addiction, 97, 487–499.

Borenstein

Hedges

Higgins

Rothstein

(2005). Comprehensive meta-analysis (version 2) [Computer software]. Englewood, NJ: Guildford Press.

Bowen

Chawla

Collins

S. E.

Witkiewitz

Hsu

Grow

… Marlatt

(2009). Mindfulness-based relapse prevention for substance use disorders: A pilot efficacy trial. Substance Abuse, 30, 295–305. doi:10.1080/08897070903250084

Bowen

Chawla

Marlatt

G. A.

(2010). Mindfulness-based relapse prevention for addictive behaviors: A clinician’s guide. New York, NY: Guilford Press.

10.

Campbell Collaboration. (2014). Campbell collaboration systematic reviews: Policies and guidelines. Retrieved from http://www.campbellcollaboration.org/lib/download/3308/C2_Policies_Guidelines_Version_1_0.pdf

11.

Card

N. A.

(2012). Applied meta-analysis for social science research. New York, NY: Guilford Press.

12.

Chiesa

Serretti

(2014). Are mindfulness-based interventions effective for substance use disorders? A systematic review of the evidence. Substance Use and Misuse, 49, 492–512.

13.

Christensen

D. R.

Dowling

N. A.

Jackson

A. C.

Brown

Russo

Francis

K. L.

Umemoto

(2013). A proof of concept for using brief dialectical behavior therapy as a treatment for problem gambling. Behaviour Change, 30, 117–137.

14.

Clark

Sharman

(2014). Commentary on Dixon et al. (2014): Understanding the abuse liability of modern electronic gaming machines. Addiction, 109, 1929–1930.

15.

Cowlishaw

Merkouris

Dowling

Anderson

Jackson

Thomas

(2012). Psychological therapies for pathological and problem gambling (review). Cochrane Database of Systematic Reviews, Art. No.: CD008937. doi:10.1002/14651858.CD008937.pub2

16.

*de Lisle

S. M.

Dowling

N. A.

Allen

J. S.

(2011). Mindfulness-based cognitive therapy for problem gambling. Clinical Case Studies, 10, 210–228.

17.

de Vibe

Bjorndal

Tipton

Hammerstrom

Kowalski

(2012). Mindfulness based stress reduction (MBSR) for improving health, quality of life, and social functioning in adults. Campbell Collaboration Systematic Reviews, 3. doi:10.4073/csr.2012.3

18.

Dixon

M. R.

Wilson

A. N.

(2014). Acceptance and commitment therapy for pathological gambling. Carbondale, IL: Shawnee Scientific Press.

19.

*Dowling

Smith

Thomas

(2006). Treatment of female pathological gambling: The efficacy of a cognitive-behavioural approach. Journal of Gambling Studies, 22, 355–372.

20.

Gooding

Tarrier

(2009). A systematic review and meta-analysis of cognitive-behavioural interventions to reduce problem gambling: Hedging our bets? Behaviour Research and Therapy, 47, 592–607.

21.

*Grant

J. E.

Donahue

C. B.

Odlaug

B. L.

Kim

S. W.

Miller

M. J.

Petry

N. M.

(2009). Imaginal desensitisation plus motivational interviewing for pathological gambling: Randomised controlled trial. The British Journal of Psychiatry, 195, 266–267.

22.

Hayes

S. C.

(2004). Acceptance and commitment therapy, relational frame theory, and the third wave of behavioral and cognitive therapies. Behavior Therapy, 35, 639–665.

23.

Hayes

S. C.

Strosahl

K. D.

Wilson

K. G.

(1999). Acceptance and commitment therapy: An experiential approach to behavior change. New York, NY: Guilford Press.

24.

Higgins

Thompson

S. G.

(2002). Quantifying heterogeneity in meta-analysis. Statistics in Medicine, 21, 1539–1558.

25.

Hodgins

D. C.

Ching

L. E.

McEwen

(2009). Strength of commitment language in motivational interviewing and gambling outcomes. Psychology of Addictive Behaviors, 23, 122. doi:10.1037/a0013010

26.

Ibanez

Blanco

Moreryra

Saiz-Ruiz

(2003). Gender differences in pathological gambling. Journal of Clinical Psychiatry, 64, 295–301.

27.

*Korman

Collins

Littman-Sharp

Skinner

McMain

Mercado

(2008). Randomized control trial of an integrated therapy for comorbid anger and gambling. Psychotherapy Research, 18, 454–465.

28.

Ladd

G. T.

Petry

N. M.

(2002). Disordered gambling among university-based medical and dental patients: A focus on Internet gambling. Psychology of Addictive Behaviors, 16, 76. doi:10.1037//0893-164X.16.1.76

29.

Ladouceur

(2005). Controlled gambling for pathological gamblers. Journal of Gambling Studies, 21, 49–57. doi:10.1007/s10899-004-1923-9

30.

Ladouceur

Gosselin

Laberge

Blaszczynski

(2001). Dropouts in clinical research: Do results reported in the field of addiction reflect clinical reality? The Behavior Therapist, 24, 44–46.

31.

Ladouceur

Lachance

Fournier

P. M.

(2009). Is control a viable goal in the treatment of pathological gambling? Behavior Research and Therapy, 47, 189–197. doi:10.1016/j.brat.2008.11.004

32.

Lakey

C. E.

Campbell

W. K.

Brown

K. W.

Goodie

A. S.

(2007). Dispositional mindfulness as a predictor of the severity of gambling outcomes. Personality and Individual Differences, 43, 1698–1710.

33.

Levin

M. E.

Hildebrandt

M. J.

Lillis

Hayes

S. C.

(2012). The impact of treatment components suggested by the psychological flexibility model: A meta-analysis of laboratory-based component studies. Behavior Therapy, 43, 741–756. doi:0005-7894/43/741–756/$1.00/0

34.

Linehan

M. M.

Dimeff

(2001). Dialectical behavior therapy in a nutshell. The California Psychologist, 34, 10–13.

35.

Lipsey

M. W.

Wilson

D. B.

(2001). Practical meta-analysis. Thousand Oaks, CA: Sage.

36.

Lopez-Viets

V. C.

Miller

W. R.

(1997). Treatment approaches for pathological gamblers. Clinical Psychology Review, 17, 689–702.

37.

Maynard

B. R.

Wilson

A. N.

Labuszienski

(2014). Mindfulness based approaches to the treatment of pathological gambling: A systematic review and meta-analysis. PROSPOERO: International prospective register of reviews. ID # CRD42014010748. Available from http://www.crd.york.ac.uk/PROSPERO/

38.

*McConaghy

Armstrong

M. S.

Blaszczynski

Allcock

(1983). Controlled comparison of aversive therapy and imaginal desensitization in compulsive gambling. The British Journal of Psychiatry, 142, 366–372.

39.

*McConaghy

Armstrong

M. S.

Blaszczynski

Allcock

(1988). Behavior completion versus stimulus control in compulsive gambling: Implications for behavioral assessment. Behavior Modification, 12, 371–384.

40.

Nastally

B. L.

(2010). Functional investigation of and treatment strategies for the near miss effect in gamblers (Order No. 3426715). Available from ProQuest Dissertations & Theses Global. (792603809). Retrieved from http://search.proquest.com/docview/792603809?accountid=8065

41.

*Nastally

B. L.

Dixon

M. R.

(2012). The effect of a brief acceptance and commitment therapy intervention on the near-miss effect in problem gamblers. Psychological Record, 62, 677–690.

42.

National Gambling Impact Study Commission. (1999). Gambling impact and behavior study. Retrieved from http://govinfo.library.unt.edu/ngisc/reports/gibstdy.pdf

43.

Oakley-Browne

M. A.

Adams

Mobberly

P. M.

(2003). Interventions for pathological gambling. Cochrane Database of Systematic Reviews, 2000, Art. No. CD001521. doi:10.1002/14651858.CD001521.pub.2

44.

Okuda

Balán

Petry

N. M.

Oquendo

Blanco

(2009). Cognitive behavioral therapy for pathological gambling: Cultural considerations. The American Journal of Psychiatry, 166, 1325–1330. doi:10.1176/appi.ajp.2009.08081235

45.

Ost

L.-G.

(2008). Efficacy of the third wave of behavioral therapies: A systematic review and meta-analysis. Behaviour Research and Therapy, 46, 296–321.

46.

Pallesen

Mitsem

Kvale

Johnsen

B. H.

Molde

(2005). Outcome of psychological treatments of pathological gambling: A review and meta-analysis. Addiction, 100, 1412–1422. doi:10.1111/j.1360-0443.2005.01204.x

47.

Petry

N. M.

(2005). Pathological gambling: Etiology, comorbitidy, and treatment. Washington, DC: American Psychological Association.

48.

Petry

N. M.

Ammerman

Bohl

Doersch

Gay

Kadden

… Steinberg

(2006). Cognitive-behavioral therapy for pathological gamblers. Journal of Consulting and Clinical Psychology, 74, 555–567. doi:10.1037/0022-006X.74.3.555

49.

Petry

N. M.

Stinson

F. S.

Grant

B. F.

(2005). Comorbidity of DSM-IV pathological gambling and other psychiatric disorders: Results from the National Epidemiologic Survey on alcohol and related conditions. Journal of Clinical Psychiatry, 66, 564–574.

50.

Pigott

T. D.

(2012). Advances in meta-analysis. New York, NY: Springer.

51.

Potenza

M. N.

Balodis

I. M.

Franco

C. A.

Bullock

Chung

Grant

J. E.

(2013). Neurobiological considerations in understanding behavioral treatments for pathological gambling. Psychology of Addictive Behaviors, 27, 380–392.

52.

Powers

M. B.

Zum Vorde Sive Vording

M. B.

Emmelkamp

P. M. G.

(2009). Acceptance and commitment therapy: A meta-analytic review. Psychotherapy and Psychosomatics, 78, 73–80.

53.

Reid

R. L.

(1986). The psychology of the near miss. Journal of Gambling Studies, 2, 32–39.

54.

Rickwood

Blaszczynski

Delfabbro

Dowling

Heading

(2010). The psychology of gambling. InPsych, 32, 11–21.

55.

Riley

(2014). Experiential avoidance mediates the association between thought suppression and mindfulness with problem gambling. Journal of Gambling Studies, 30, 163–171.

56.

Ruiz

F. J.

(2012). Acceptance and commitment therapy versus traditional cognitive behavioral therapy: A systematic review and meta-analysis of current empirical evidence. International Journal of Psychology and Psychological Therapy, 12, 333–357.

57.

Segal

Z. V.

Williams

J. M. G.

Teasdale

(2002). Mindfulness-based cognitive therapy for depression: A new approach to preventing relapse. New York, NY: Guilford Press.

58.

Sharma

M. G.

Sharma

(2012). Effect of psychotherapy on pathological gamblers. SIS Journal of Projective Psychology & Mental Health, 19, 56–60.

59.

Shonin

Van Gordon

Griffiths

M. D.

(2014). Cognitive behavioral therapy (CBT) and meditation awareness training (MAT) for the treatment of co-occurring schizophrenia and pathological gambling: A case study. International Journal of Mental Health and Addiction, 12, 181–196.

60.

Swain

Hancock

Hainsworth

Bowman

(2013). Acceptance and commitment therapy in the treatment of anxiety: A systematic review. Clinical Psychology Review, 33, 965–978.

61.

*Toneatto

Pillai

Courtice

E. L.

(2014). Mindfulness-enhanced cognitive behavior therapy for problem gambling: A controlled pilot study. International Journal of Mental Health and Addiction, 12, 197–205.

62.

Toneatto

Vettese

Nguyen

(2007). The role of mindfulness in cognitive-behavioural treatment of problem gambling. Journal of Gambling Issues, 19, 91–100.

63.

Valentine

J. C.

Pigott

T. D.

Rothstein

(2010). How many studies do you need? A primer on statistical analysis for meta-analysis. Journal of Educational and Behavioral Statistics, 35, 215–247.

64.

Welte

Barnes

G. M.

Wieczorek

Tidwell

M. C.

Parker

(2001). Alcohol and gambling pathology among U.S. adults: Prevalence, demographic patterns and comorbidity. Journal of Studies on Alcohol, 62, 706–712.

65.

Welte

J. W.

Wieczorek

W. F.

Barnes

G. M.

Tidwell

M. C.

(2006). Multiple risk factors for frequent and problem gambling: Individual, social, and ecological. Journal of Applied Social Psychology, 36, 1548–1568.

66.

Westphal

J. R.

(2008). How well are we helping problem gamblers? An update to the evidence base supporting problem gambling treatment. International Journal of Mental Health and Addiction, 6, 249–264.

67.

Whiting

S. W.

Dixon

M. R.

(2013). Effects of mental imagery on gambling behavior. Journal of Gambling Studies, 29, 525–534.

68.

Williams

R. J.

Volberg

R. A.

Stevens

R. M.

(2012). The population prevalence of problem gambling: Methodological influences, standardized rates, jurisdictional differences, and worldwide trends. Ontario, Canada: Ontario Problem Gambling Research Centre.

69.

Wilson

A. N.

Salas-Wright

C. P.

Vaughn

M. G.

Maynard

B. R.

(2015). Gambling prevalence rates among immigrants: A multigenerational examination. Addictive Behaviors, 42, 79–85.

70.

Zgierska

Rabago

Chawla

Kushner

Koehler

Marlatt

(2009). Mindfulness mediation for substance use disorders: A systematic review. Substance Abuse, 30, 266–294.

Supplementary Material

Please find the following supplemental material available below.

For Open Access articles published under a Creative Commons License, all supplemental material carries the same license as the article it is associated with.

For non-Open Access articles published, all supplemental material carries a non-exclusive license, and permission requests for re-use of supplemental material or any part of supplemental material shall be sent directly to the copyright owner as specified in the copyright notice associated with the article.

0.00 MB

0.14 MB