Assessment http://asm.sagepub.com/ Psychometric Properties of the Five Facets Mindfulness Questionnaire (FFMQ) in a Meditating and a Non-meditating Sample Esther I. de Bruin, Maurice Topper, Jan G. A. M. Muskens, Susan M. Bögels and Jan H. Kamphuis Assessment 2012 19: 187 DOI: 10.1177/1073191112446654 The online version of this article can be found at: http://asm.sagepub.com/content/19/2/187 Published by: http://www.sagepublications.com Additional services and information for Assessment can be found at: Email Alerts: http://asm.sagepub.com/cgi/alerts Subscriptions: http://asm.sagepub.com/subscriptions Reprints: http://www.sagepub.com/journalsReprints.nav Permissions: http://www.sagepub.com/journalsPermissions.nav Citations: http://asm.sagepub.com/content/19/2/187.refs.html >> Version of Record - May 14, 2012 What is This? Downloaded from asm.sagepub.com at Universiteit van Amsterdam SAGE on May 31, 2012 446654 1112446654de Bruin et al.Assessment © The Author(s) 2012 ASM19210.1177/107319 Reprints and permission: sagepub.com/journalsPermissions.nav Psychometric Properties of the Five Facets Mindfulness Questionnaire (FFMQ) in a Meditating and a Non-meditating Sample Assessment 19(2) 187­–197 © The Author(s) 2012 Reprints and permission: sagepub.com/journalsPermissions.nav DOI: 10.1177/1073191112446654 http://asm.sagepub.com Esther I. de Bruin1, Maurice Topper1, Jan G. A. M. Muskens2, Susan M. Bögels1, and Jan H. Kamphuis Abstract The factor structure, internal consistency, construct validity, and predictive validity of the Dutch version of the Five Facet Mindfulness Questionnaire (FFMQ-NL) were studied in a sample of meditators (n = 288) and nonmeditators (n = 451). A five-factor structure was demonstrated in both samples, and the FFMQ-NL and its subscales were shown to have good internal consistencies. Meditators scored higher on all facets of the FFMQ-NL than the participants in the nonmeditating sample. For both samples, expected negative correlations between most mindfulness facets (all except for the Observing facet) and the constructs of alexithymia, thought suppression, rumination, worry, and dissociation were found. The Observing facet of the FFMQ-NL showed an unexpected positive correlation with thought suppression in the nonmeditating sample. Furthermore, as expected, mindfulness facets were negatively related to psychological symptoms, and all mindfulness facets except for Observing and Describing significantly predicted psychological symptoms. Overall, the Dutch FFMQ demonstrated favorable psychometric properties, commensurate with its (original) English language version. Keywords FFMQ, mindfulness, meditation, internal consistency, construct validity, psychometric properties Mindfulness is paying attention in a particular way: on purpose, in the present moment, and nonjudgmentally (KabatZinn, 1994). Mindfulness-based treatments are extremely popular and are still rapidly increasing worldwide. In the United States alone, mindfulness-based treatments are applied in more than 250 health care centers (Jha, Krompinger, & Baime, 2007). Mindfulness is originally based on Eastern (Buddhist) meditation practices (Baer, 2003; Hanh, 1976). Through the practice of meditation, an ability to direct one’s attention can be developed. A main goal of mindfulnessbased interventions is a moment-to-moment attempt to perceive an event and let it be registered with full awareness, as it is, without distortion from associated thoughts from the observer (Kabat-Zinn, Lipworth, & Burney, 1985). Contrary to conventional (cognitive) behavioral therapies, mindfulnessbased interventions focus on universal difficulties rather than on specific problems (Bögels, Hoogstad, van Dun, de Schutter, & Restifo, 2008). The underlying assumption of mindfulness-based interventions is that experiencing the present moment nonjudgmentally and openly can effectively reduce the effects of stressors, since overinvolvement in the past or future when dealing with stress can be related to symptoms of anxiety and depression. Two main streams of mindfulness-based treatments are Mindfulness-Based Stress Reduction (MBSR; Kabat-Zinn, 1994) and Mindfulness-Based Cognitive Therapy (MBCT; Segal, Williams, & Teasdale, 2002). MBSR programs are run in groups with a standardized manual in which meditation exercises, meditation home work, relaxation skills, emotion and coping strategies, and explanations about the physiology of stress are taught in an 8-week session. In general, the goal is to increase mindful awareness in stressful situations and practice, responding intentionally rather than automatically reacting to stressful events. MBSR is considered a general stress 1 University of Amsterdam, Amsterdam, the Netherlands Private Psychotherapy Practice, Zevenaar, the Netherlands 2 Corresponding Author: Esther I. de Bruin, University of Amsterdam, Faculty of Behavioral and Social Sciences, Research Institute of Child Development and Education, Nieuwe Prinsengracht 130, 1018 VZ Amsterdam, the Netherlands Email: e.i.debruin@uva.nl Downloaded from asm.sagepub.com at Universiteit van Amsterdam SAGE on May 31, 2012 188 Assessment 19(2) reduction program for both clinical and nonclinical populations (Hayes, Follette, & Linehan, 2004). Similarly, MBCT also consists of an 8-week standardized protocol applied in group format but is mainly used in the relapse prevention for chronic major depressive disorder (Hayes et al., 2004). MBCT includes several components of MBSR but techniques from cognitive therapy are added to this. However, it is important to note that the goal of MBCT, as opposed to more conventional cognitive therapy, is not to change the content of the patients’ negative thoughts but to learn to be more open, aware, and accepting of present-moment experiences as they are (Baer, 2003; Hayes et al., 2004). Mindfulness-based interventions have been shown to be effective for a variety of problems in children, adolescents, and adults. They effectively reduce stress, anxiety, depression, chronic pain, burn out, and relapse prevention of alcohol and substance abuse (e.g., Baer, 2003; Carmody & Baer, 2008; Cohen-Katz et al., 2005; Hofmann, Sawyer, Witt, & Oh, 2010; Kabat-Zinn et al., 1992; Kuyken et al., 2008; Segal et al., 2002; Shapiro, Astin, Bishop, & Cordova, 2005; Teasdale et al., 2000; Witkiewitz, Marlatt, & Walker, 2005). In a meta-analysis, Baer (2003) found a large posttreatment and a medium effect size at follow-up of mindfulnessbased trainings. Furthermore, in another meta-analysis of 64 studies of mindfulness-based interventions (Grossman, Niemann, Schmidt, & Walach, 2004), an average overall effect size of .54 was shown, but it was also shown that only seven studies were randomized controlled trials. Subsequently, in their meta-analytic review, Hofmann and colleagues assessed the effectiveness of mindfulness-based therapy in reducing symptoms of anxiety and depression in clinical populations. When all different samples were examined as a whole (review of 39 studies including patients with cancer, anxiety disorders, depression, and other medical or psychiatric disorders) effect sizes of mindfulness-based interventions were .63 and .59 for anxiety and mood symptoms, respectively. If, however, only studies of patients with anxiety and mood disorders were included, large effect sizes of .97 and .95 for anxiety and depression symptoms, respectively, were reported (Hofmann et al., 2010). Although randomized studies demonstrated the efficacy of mindfulness-based interventions (e.g., Baer, 2003; Grossman et al., 2004; Hofmann et al., 2010; Salmon et al., 2004; Segal et al., 2002), theoretical progress is hindered by a lack of valid and reliable mindfulness questionnaires that assess the underlying processes that lead to positive outcomes. Mindfulness questionnaires with strong psychometric properties are needed to determine whether mindfulness skills do indeed increase after participation in a mindfulnessbased intervention in clinical and nonclinical populations and to assess whether this increase mediates the subsequent decrease in psychological or psychiatric symptoms (e.g., Baer, Smith, & Allen, 2004; Baer, Smith, Hopkins, Krietemeyer, & Toney, 2006; Bishop et al., 2004). This need for psychometrically sound mindfulness instruments applies even more so to the Netherlands where translation and validation of mindfulness questionnaires is still in its infancy. The Five Facet Mindfulness Questionnaire (FFMQ; Baer et al., 2006; Baer et al., 2008; Van Dam, Earlywine, & Danoff-Burg, 2009) is currently the most frequently studied mindfulness questionnaire. A particular strength of the FFMQ is that it is based on a factor analysis of items from the five most widely used mindfulness questionnaires: the Freiburg Mindfulness Inventory (Buchheld, Grossman, & Walach, 2001), the Mindful Attention Awareness Scale (Brown & Ryan, 2003), the Mindfulness Questionnaire (Chadwick, Hember, Mead, Lilley, & Dagnan, 2005), the Kentucky Inventory of Mindfulness Skills (Baer et al., 2004), and the Cognitive and Affective Mindfulness Scale (Feldman, Hayes, Kumar, & Greeson, 2004). Accumulating data suggest that the five-factor structure of the FFMQ is robust for various types of samples, and consistent evidence has underscored its construct validity (see Baer et al., 2006; Baer et al., 2008). The aim of the present study is to assess key psychometric properties of the Dutch FFMQ (FFMQ-NL) in a meditating sample and a nonmeditating sample and to compare these to findings of the original English version of the FFMQ. Factor structure and internal consistency were examined as well as correlations with selected constructs including thought suppression, ruminative coping, dissociative behavior, tendency to worry, and the ability to identify and describe feelings (alexithymia). Furthermore, the relationship between mindfulness and psychological symptoms was assessed as well as the predictive value of the five mindfulness facets in predicting psychological symptoms. The following specific hypotheses were tested. Hypothesis 1: If meditation does indeed cultivate mindfulness, we would expect the participants in the meditating sample to have higher mean scores on the FFMQ-NL than the participants in the nonmeditating sample. Hypothesis 2: Based on studies of the original FFMQ (Baer et al., 2006; Baer et al., 2008), we expected the FFMQ-NL to consist of a five-factor structure in both samples. Hypothesis 3: Since meta-analytic reviews have shown positive effects of mindfulness-based interventions on psychological well-being and psychiatric symptoms, we expected a positive relationship between mindfulness and the measure of psychological symptoms. Furthermore, we expected each of the different mindfulness facets to predict psychological symptoms. Downloaded from asm.sagepub.com at Universiteit van Amsterdam SAGE on May 31, 2012 189 de Bruin et al. Hypothesis 4: Based on previous findings (Baer et al., 2006; Baer et al., 2008), we expected thought suppression, rumination, dissociative behavior, worry, and alexithymia to be negatively related to the mindfulness facets. Method Participants and Procedure The first sample consisted of first year undergraduate psychology students at the University of Amsterdam who were required to participate in mass testing for course credit. Each participant completed a set of computer-based questionnaires. A total of 451 participants completed the FFMQ-NL and were included in the analyses (age: M = 20.70, SD = 4.5, range = 17-42; 74% female). The second sample consisted of participants who were specifically recruited for their meditation experience through meditation centers in the Netherlands and Belgium. Meditation centers were identified through an Internet search and contacted by phone. When interested in participation, information was sent by e-mail to the centers with the request to forward this e-mail to people on their mailing list. Subjects willing to participate could do so by following up on an Internet link that directed them to web-based versions of the different questionnaires. Cooperation was completely voluntary, and participants received no monetary compensation. To increase the likelihood of participation, a smaller set of questionnaires was used for this sample (see below).1 A total of 288 participants completed the FFMQ-NL and were included in the analyses (age: M = 53.10, SD = 10.92, range = 17-79; 55% female). The education level of our meditation sample was high, which is commonly observed among meditation practitioners (Baer et al., 2008). University-level education was reported by 80% of our sample, and 45% of this group reporting holding a graduate degree. The mean number of years of meditation practice was 12.88 (SD = 9.15). The average amount of time per week spent on formal meditation practice was 4 hours and 47 minutes (SD = 3.66). Measures FFMQ The FFMQ (Baer et al., 2006) consists of 39 items that are rated on a 5-point Likert-type scale (1 = never or very rarely true, 5 = very often or always true). Five facets are scored: Observing, Describing, Acting with awareness, Nonjudging, and Nonreactivity. The Observing facet measures the tendency to notice or attend to internal and external experiences, such as sensations, emotions, cognitions, sounds, sights, and smells. Example items are “I remain present with sensations and feelings even when they are unpleasant or painful” and “I pay attention to sounds, such as clocks ticking, birds chirping, or cars passing.” Describing measures the tendency to describe and label these experiences with words. Items include “I’m good at finding the words to describe my feelings” and “My natural tendency is to put my experiences into words.” The Acting with awareness facet refers to bringing full awareness and undivided attention to current activity or experiences. Example items are “I rush through activities without being really attentive to them” and “I find it difficult to stay focused on what’s happening in the present.” Nonjudging refers to a nonevaluative stance toward inner experiences. Items include “I tend to evaluate whether my perceptions are right or wrong” and “I think some of my emotions are bad or inappropriate and I shouldn’t feel them.” Nonreactivity measures the tendency to allow thoughts and feelings to come and go, without getting caught up in them or carried away by them. Items include “Usually when I have distressing thoughts or images, I step back and am aware of the thought or image without getting taken over by it.” Psychometric properties of the Dutch version of the FFMQ are the focus of the present article. Dissociative Experiences Scale–II (DES-II) The DES-II is a 28-item self-report trait measure of dissociative behavior frequently used as a dissociative pathologyscreening instrument in both clinical and nonclinical populations (Bernstein, Carlson, & Putnam, 1993; Bernstein & Putnam, 1986). An illustrative item is, “Some people have the experience of driving a car and suddenly realizing that they don’t remember what has happened during all or part of the trip.” Participants rate the frequency with which they experience the phenomenon described on a visual analog scale ranging from 0 = not at all to 100 = very much. A meta-analytic validation of the DES, including studies on the Dutch translation, showed a high internal consistency in both normal and clinical populations (mean α = .93), high convergent validity with other dissociative experiences questionnaires and interview schedules, and good validity in the prediction of dissociative disorders (Van IJzendoorn & Schuengel, 1996). In this study reliabilities are α = .96 for the nonmeditating sample and α = .88 for the meditating sample. General Health Questionnaire (GHQ-30) The GHQ was developed as a screening tool to detect respondents likely to have or be at risk for developing psychiatric disorders (Goldberg, 1972; Goldberg et al., 1978). The GHQ has been translated to 38 languages and is available in a variety of versions using 12, 28, 30, or 60 items. Downloaded from asm.sagepub.com at Universiteit van Amsterdam SAGE on May 31, 2012 190 Assessment 19(2) In our study, the 30-item version was used. Although different factor solutions have been suggested, all items refer to the common mental health domains of depression (“Have you been thinking of yourself as a worthless person?”), anxiety (“Have you been getting out of the house as much as usual?”), insomnia (“Have you lost much sleep over worry?”), and social withdrawal (“Have you spent much time chatting with people?”). Items are rated on a scale ranging from 0 = not at all to 3 = much more than usual. The Dutch version of the GHQ has been shown to have good psychometric properties (Ormel, Koeter, Van den Brink, & Giel, 1989). Internal consistency for this studies meditating sample was high (α = .92). Penn State Worry Questionnaire (PSWQ) The PSWQ (Meyer, Miller, Metzger, & Borkovec, 1990) was developed to measure aspects of clinically significant worry. It measures the tendency, intensity, and uncontrollability of worry and consists of 16 items rated on a 5-point Likert-type scale, with values ranging from 1 = not at all typical of me to 5 = very typical of me (i.e., “I am always worrying about something”, or “I have been a worrier all my life”). Meyer et al. (1990) carried out a series of studies in which it was shown that the PSWQ had high internal consistency in clinical and nonclinical samples (α varying from .88 to .95), good test–retest reliability in a variety of samples (r ranging between .74 and .92), and good convergent and discriminant validity. The Dutch version of the PSWQ has also been shown to have a high internal consistency in clinical (α = .86; Kerkhof et al., 2000) as well as in nonclinical samples (α between .88 and .90; Van Rijsoort, Emmelkamp, & Vervaeke, 1999; Van Rijsoort, Vervaeke, & Emmelkamp, 1997). Cronbach’s alpha value was .92 in both of our samples. Ruminative Responses Scale (RRS) The RRS is a subscale of the Response Styles Questionnaire and consists of 22 items on a Likert-type scale, with values ranging from 1 (almost never) to 4 (almost always). It assesses the tendency to respond to depressed moods with a self-focus (items such as “Why do I have problems that other people don’t have?”), a symptom-focus (items such as “Think about your feeling of fatigue and achiness”), and a focus on possible consequences and causes of this depressed mood (items such as “I won’t be able to do my job if I don’t snap out of this”). The RRS has been shown to have a good internal consistency (α = .82), moderate to high test–retest reliability (r = .47, p < .001), and has good validity in the prediction of depression (e.g., NolenHoeksema, 2000; Spasojevic & Alloy, 2001; Treynor, Gonzalez, & Nolen-Hoeksema, 2003). In this study, the authorized Dutch translation of the RRS was used (RRS-NL; Raes, Hermans, & Eelen, 2003) and good internal consistency for this study’s student sample (α = .91) was shown. Also, the subscales of self-focus and symptom-focus as presented by Bagby and Parker (2001) were included in the analyses. Toronto Alexithymia Scale (TAS-20) The TAS-20 is a measure of the alexithymia construct, which represents the lack of ability to identify and describe feelings, as well as a lack of interest in feelings, cognitions, or motivations. Self-report statements are rated on a 5-point Likert-type scale ranging from 1 = completely agree to 5 = completely disagree. The TAS-20 has been translated into 18 languages, and results from 19 different countries show strong support for the generalizability of a three-factor structure across different cultures and languages (e.g., Parker, Taylor, & Bagby, 2003; Taylor, Ryan, & Bagby, 1985; Tsaousis et al., 2010; Zhu, Yi, Ryder, Taylor, & Bagby, 2007). For the Dutch population, internal consistencies for total TAS-20 ranged from .79 to .80 (Taylor, Bagby, & Parker, 2003). Furthermore, alexithymia was significantly (negative) correlated with psychological mindedness and need for cognition (r = −.68, p < .05, and r = −.55, p < .05, respectively) and positively correlated with depression (r = .36, p < .01; Bagby, Taylor, & Parker, 1994). In the current student sample, reliability of the Dutch TAS-20 (Kooiman, Spinhoven, & Trijsburg, 2002) was high (α = .85). White Bear Suppression Inventory (WBSI) The WBSI is a 15-item questionnaire that measures to what extent unwanted thoughts are suppressed by deliberate attempts to avoid or get rid of these thoughts (Wegner & Zanakos, 1994). Subjects are asked to rate items on a 5-points Likert-type scale (1 = strongly disagree; 5 = strongly agree). The Dutch version of the WBSI has been shown to have good internal consistency (α = .89) and good test–retest reliability (p < .001), and factor analysis revealed a one-factor solution, which is consistent with the original WBSI (Muris, Merckelbach, & Horselenberg, 1996). Internal consistency in both samples of the current study was high (α = .89 in the nonmeditating sample, α = .88 in meditating sample). Statistical Analyses Analyses were directed by the main findings of previous research on the original English language version of the FFMQ (Baer et al., 2006; Baer et al., 2008). t Tests were conducted to compare the five mindfulness facets and the FFMQ-NL total score across both study samples. A confirmatory factor analysis (CFA) was carried out to examine Downloaded from asm.sagepub.com at Universiteit van Amsterdam SAGE on May 31, 2012 191 de Bruin et al. Table 1. Intercorrelations of the Five Mindfulness Facets of the FFMQ-NL Facet Nonjudging Describing Nonreacting Acting with awareness Observing Nonjudging Describing Nonreacting Acting With Awareness .25** .25** .14* .39** .35** .08 .13* .36** .37** .19** .27** .37** .18** .31** .39** Observing −.03 .26** .03 .03 .29** Note. Nonmeditating sample upper right of table; meditating sample lower left of table. *p ≤ .05. **p ≤ .01. Table 2. Results of Confirmatory Factor Analyses and Multigroup Confirmatory Factor Analysis Model Students (n = 451) One factor Five factor Hierarchical five factors Four factors Hierarchical four factors Meditators (n = 288) Five factor Hierarchical five factors Structure invariance Configural Metric invariance df χ2 χ2diff CFI NNFI RMSEA 90 80 85 48 50 2236.43*** 124.89*** 164.08*** 87.40*** 92.26*** 41.92** 4.86 .53 .99 .98 .99 .99 .45 .98 .97 .98 .98 .23 .04 .05 .04 .04 80 85 139.07*** 158.66*** 19.59** .98 .98 .97 .97 .05 .05 170 180 251.06*** 257.61*** 6.55 .98 .98 .98 .98 .05 .05 Note. df = degrees of freedom; χ2diff = chi-square difference; CFI = comparative fit index; NNFI = nonnormed fit index; RMSEA = root mean square error of approximation. Chi-square difference tests were conducted to compare each hierarchical model with its corresponding nonhierarchical model. The one-factor model was ruled out; the difference tests were conducted to determine the value of a hierarchical framework. **p < .01. ***p < .001. the factor structure and the fit of this factor structure. Internal analyses tested the internal consistency (Cronbach’s alpha) across samples and intercorrelations of the five mindfulness facets. For the external analyses, correlations with mental health and personality-related constructs were calculated to test construct validity. To assess to what extent the five different mindfulness facets predicted general mental health or psychological symptoms (as measured by the GHQ-30), a linear regression analysis was conducted. Results Internal Consistency and Intercorrelations In both our samples internal consistency for the FFMQ-NL total score was good (nonmeditating sample α = .85; meditating sample α = .90). On the facet level, internal consistencies were in the adequate-to-good range. The following alpha coefficients were obtained (nonmeditating sample first): Nonjudging = .87 and .89; Describing = .85 and .86; Nonreactivity = .71 and .83; Acting with awareness = .81 and .86; and Observing = .70 and .72. Intercorrelations of the five mindfulness facets for both samples are shown in Table 1. Overall the facets show modest but significant correlations, suggesting the facets represent related but distinct constructs. However, this pattern of correlations is not as clear for the Observing facet. In the student sample, Observing only shows a significant positive correlation with the Describing facet. The meditating sample shows a more unitary pattern; all correlations are positive and range from .13 to .39. Confirmatory Factor Analysis A CFA using LISREL 8.80 was conducted to replicate the model testing as conducted by Baer et al. (2006), closely replicating their item parceling and set of fit indices (i.e., chi-square, comparative fit index [CFI], nonnormed fit index [NNFI], and root mean square error of approximation [RMSEA]). As can be seen in Table 2, the pattern of fit indices across models in the student sample is remarkably similar to that obtained by Baer et al. (2006). Specifically, we also found that a one-factor model does not provide a good fit to the data, suggesting that the collection of item parcels does not have a one-dimensional structure. The Downloaded from asm.sagepub.com at Universiteit van Amsterdam SAGE on May 31, 2012 192 Assessment 19(2) Table 3. Means (SD) of Five Facets and Total FFMQ-NL Score in Nonmeditating (n = 451) and Meditating Samples (n = 288) Scale Nonjudging Describing Nonreacting Acting with awareness Observing Total FFMQ-NL Students Meditators t Value † Effect Size (Cohen’s d) 27.65 (5.82) 28.08 (4.99) 22.07 (3.64) 25.29 (4.63) 32.13 (5.52) 30.68 (4.80) 26.01 (3.75) 29.04 (4.53) 10.39 7.00† 14.17† 10.80† 0.79 0.53 1.07 0.82 26.46 (4.30) 129.55 (13.94) 31.10 (3.62) 148.94 (14.51) 15.16† 18.13† 1.17 1.36 Note. FFMQ-NL = Dutch version of Five Facet Mindfulness Questionnaire. † p ≤ .008. Table 4. Correlations Between FFMQ-NL Mindfulness Facets and Other Constructs in Nonmeditating (n = 451) and Meditating (n = 288) Samples Construct Student sample Alexithymia (TAS) Dissociation (DES-II) Worry (PSWQ) Rumination (RRS)   Self-focus   Symptom focus Thought sup. (WBSI) Meditator sample Dissociation (DES-II) Worry (PSWQ) Thought sup. (WBSI) Psyc. sym. (GHQ-30) Nonjudging Describing Nonreacting Acting With Awareness Observing FFMQ Total −.41** −.28** −.41** −.41** −.35** −.36** −.50** −.59** −.18** −.24** −.16** −.09 −.21** −.15** −.20** −.06 −.44** −.21** −.17** −.17** −.28** −.43** −.26** −.22** −.27** −.18** −.32** −.34** −.25** .00 .07 .08 .09 .05 .13** −.66** −.28** −.43** −.35** −.25** −.36** −.41** −.46** −.47** −.46** −.26** −.21** −.14* −.21** −.06 −.33** −.53** −.33** −.35** −.42** −.51** −.42** −.26** −.11 −.21** −.11 −.14* −.49** −.58** −.49** −.32** Note. DES-II = Dissociative Experiences Scales; FFMQ = Five Facet Mindfulness Questionnaire; GHQ-30 = General Health Questionnaire–30 items; PSWQ = Penn State Worry Questionnaire; Psyc. sym. = Psychological symptoms; RRS = Ruminative Responses Scale; TAS = Toronto Alexithymia Scale; Thought sup. = Thought suppression; WBSI = White Bear Suppression Inventory. Largest correlations are shown in bold. *p ≤ .05. **p ≤ .01. other four models tested show CFI and NNFI values above .90 and RMSEA levels below .05 indicating a good fit for all models. The hierarchical model with five factors fit significantly worse than the nonhierarchical model. Removing the observe facet suggested the plausibility of a four-factor hierarchical structure to mindfulness in the student sample. In the meditating sample, a nonhierarchical five-factor model fit the data well. Although the more parsimonious model with a hierarchical structure of five mindfulness facets and an overarching mindfulness factor showed loss of fit, CFI, NNFI, and RMSEA values indicated that this model fit the sample well. To further test factor structure invariance across the Dutch and English language versions, we conducted a multigroup CFA. We tested the hierarchical five-factor model in our Dutch meditator sample and an English language meditator sample (n = 116) provided by Lykins and Baer (2009). We report the fit of the models tested in Table 2. The models showed that the same factor structure holds across groups (configural model) and that the factor loadings across groups are equal (metric invariance). The fit indices (CFI, NNFI, and RMSEA) of both models indicate a good fit. Meditating Versus Nonmeditating Participants Differences between meditating and nonmeditating participants were tested using independent samples t tests. With Bonferroni correction for six comparisons, the alpha level was set at .008 (.05/6). As can be seen in Table 3, participants in the meditating sample scored significantly higher on FFMQ-NL total (p ≤ .008) and on all of its facets (p ≤ .008) than participants in the nonmeditating sample. Effect sizes of the differences varied from d = 0.53 (medium effect) to d = 1.36 (large effect). Construct Validity Table 4 shows the correlations between the mindfulness scores and related variables. Alexithymia showed the Downloaded from asm.sagepub.com at Universiteit van Amsterdam SAGE on May 31, 2012 193 de Bruin et al. Table 5. Regression Analyses Showing Prediction of Psychological Symptoms by Mindfulness Facets in Meditating Sample (n = 288) Predictor Nonjudging Describing Nonreacting Acting with awareness Observing B SE Beta p −.23 .09 −.78 −.30 .04 .12 .13 .18 .15 .18 −.12 .04 −.27 −.13 .01 .049* .481 .000** .043* .825 Note. Predictor variables entered simultaneously into a single regression equation. R2 for model = .16. *p ≤ .05. **p ≤ .01. strongest negative correlation with the Describing facet (r = −.59; p ≤ .01). Dissociation is most strongly related with the Nonjudging facet in both samples (r = −.28, p ≤ .01, and r = −.46, p ≤ .01, for the nonmeditating and the meditating samples, respectively). As expected, worry, rumination, and thought suppression were significantly (negative) related to the Nonjudging, Describing, Nonreacting, and Acting with awareness facets (see Table 4 for details) in both samples. Contrary to expectations, the Observing facet was positively related to thought suppression (r = .13; p ≤ .01, nonmeditating sample). Moreover, apart from a significant negative association with alexithymia (r = −.25; p ≤ .01), the Observing facet was not significantly related to any of the other constructs in the nonmeditating sample (r = .00, r = .07, and r = .08 for dissociation, worry, and rumination, respectively). In the meditating sample, correlations with the Observing facet were negative as expected but only reached statistical significance for worry (r = −.21; p ≤ .01). Predictive Validity As expected, the total score on the GHQ-30 was significantly negatively related to total FFMQ-NL score (r = −.14; p ≤ .05). All mindfulness facets, apart from Describing, reached statistical significance in these negative correlations (see Table 4). More self-reported psychological symptoms were inversely related to mindfulness. The results of the regression analysis examining the predictive validity of mindfulness facets can be seen in Table 5 (meditating sample only). All facets except for Observing and Describing significantly predicted psychological symptoms (p ≤ .05 for the Nonjudging and Acting with awareness facets and p ≤ .01 for the Nonreacting facet). Discussion The aim of this study was to assess psychometric properties of one of the first officially translated Dutch adult mindfulness questionnaires, the FFMQ-NL. Of our six measured constructs, four were included in studies by Baer and colleagues, and alexithymia and thought suppression were measured with the same instruments. In general, this study further validated the construct of mindfulness as measured by the FFMQ, in another country and a different language and possibly a slightly different culture. We can draw several conclusions from the present study. First, mindfulness scores were higher (on all five facets) for the meditating sample compared with the nonmeditating sample, as expected. Thus, by practicing regular (i.e., daily or a few times weekly) meditation for several years, one attends more to internal and external experiences, is better able to describe these experiences in a nonjudgmental way, lets thoughts and feelings come and go without having to react to them, and one improves in bringing attention and awareness into the present moment. Results are in agreement with findings on the original English language version of the FFMQ (Baer et al., 2006; Baer et al., 2008). Second, results of the CFA showed a hierarchical fivefactor structure, with one higher order factor representing mindfulness in general as well as five lower order factors representing the five mindfulness facets (Nonjudging, Describing, Nonreactivity, Observing, and Acting with awareness). The internal consistencies were good in both samples on FFMQ-NL total score and adequate to good when separate subscales were examined. We can thus conclude that also in the Netherlands, where the influence of mindfulness has a shorter history than in the United States, and only started to emerge more deeply in recent years, the construct of mindfulness, as measured by the FFMQ, seems to cover the same underlying dimensions and therefore has a similar representation in both countries. Third, the relationship between mindfulness and psychological symptoms was negative as expected. Higher self-reports of mindfulness were related to lower selfreported psychological symptoms related to depression, anxiety, anhedonia, and insomnia. This is in accordance with many previous studies that showed positive effects of mindfulness-based training on psychological well-being and quality of life (i.e., Baer, 2003; Kabat-Zinn, 1994; Segal et al., 2002). In addition, it was shown (in the meditating sample only) that three of the five facets significantly predicted psychological symptoms (Nonjudging, Nonreactivity, and Acting with awareness). These findings were similar to previous findings in which also three facets were found to predict psychological symptoms (Baer et al., 2008). However, in our sample the Describing facet did not predict psychological symptoms (whereas Nonreactivity did), whereas in the previous study (Baer et al., 2008) the Describing facet showed large predictive value (whereas Nonreactivity did not). This difference might be related to the fact that Baer et al. (2008) included meditators and nonmeditators in these analyses, whereas we included meditators only. For future studies, we need to assess psychological well-being also in a nonmeditating sample. Of further importance here is that the Observing facet was not included in the regression analyses of the earlier study since this Downloaded from asm.sagepub.com at Universiteit van Amsterdam SAGE on May 31, 2012 194 Assessment 19(2) facet showed unexpected correlations with psychological symptoms. In our study, Observing also showed correlations in the unexpected direction but not with respect to psychological symptoms. We therefore included all five facets in the regression analyses. Furthermore, psychological symptoms were measured by slightly different instruments in the current study as compared with the study of Baer et al. (2008). However, the commonality in both studies is that mindfulness facets have predictive validity in predicting psychological or mental health. Fourth, overall mindfulness was negatively related, as expected, to a variety of other constructs, such as dissociation, worry, rumination, thought suppression, and alexithymia. This was true for the meditating and the nonmeditating samples. For instance, all five mindfulness facets showed a negative relationship with the measure of alexithymia, but the Describing facet in particular correlated most negatively with alexithymia. Alexithymia entails difficulties with recognizing and labeling emotional states (note the parallel to the Describing facet of the FFMQ) and a lack of interest in inner experiences. Particularly, the recognizing and labeling of emotional states is also measured in the items of the Describing facet (i.e., “I have trouble thinking of the right words to express how I feel about things”), which may explain why alexithymia is most strongly related to this facet. Rumination is characterized by repetitive thoughts concerning past, present, and future problems or negative experiences. This negative cognitive activity consists for a considerable part of a negative judgmental style that may explain why the strongest negative relationship was found with the Nonjudging facet. Worry (a cardinal feature of Generalized Anxiety Disorder [GAD]) is characterized by repetitive thoughts concerning perceived future threats. People with GAD report heightened emotional intensity and difficulty recovering from an emotional episode. Worry functions to avoid a sudden shift from a positive state to a negative emotion that is otherwise experienced as extremely aversive (Newman & Llera, 2011). It might be for this reason that worry was most strongly related (negatively) to the Nonreactivity facet. Thought suppression involves judgmental and self-critical attitudes about ones thoughts and emotions. Since mindfulness covers an attitude of acceptance of all thoughts, good or bad, it is in accordance with our expectations that thought suppression showed the strongest negative relationship with the Nonjudging facet. Dissociative behavior can range from normal experiences, such as daydreams and automatisms, to dissociative pathology. Since dissociation is related to acting without awareness, we would have expected to find the strongest negative association with the Acting with awareness facet. This was not quite the case in our data. The strongest association was found with Nonjudging; however, the difference with the association with Acting with awareness facet was small. Important to note here is the Observing facet. This facet did not correlate significantly with dissociation, worry (only student sample), or rumination as was expected. And even more surprising, the Observing facet showed a positive relationship with thought suppression in the student sample and a negative (but not significant) relationship in the meditating sample. Albeit a surprising finding, Baer et al. (2008) showed the same results. Thus, for nonmeditating first year students, the more one attends to internal and external sensations and emotions, the more judgmental and self-critical one is about having those thoughts and emotions or vice versa. This is in accordance with previous literature that shows that self-focused attention may be maladaptive, at least in nonmeditating samples (i.e., Bögels & Mansell, 2004; Mor & Winquist, 2002). In meditation or mindfulness courses, one is taught to observe in a more neutral way to simply observe all sensations that one is presented with at that present moment and make no further judgments. This most likely reduces being judgmental and critical toward one’s internal experiences. Our student sample did not have this meditation experience and therefore this relationship might have been opposite to what would be expected. It seems therefore plausible that the Observing items might have a different meaning for meditators and nonmeditators. This idea is supported by the findings of Baer et al. (2008) in that the relationship between Observing and psychological symptoms and well-being varied with meditation experience. In the meditating sample a higher score on Observing was related to high psychological well-being, whereas in nonmeditating samples this relationship was nonsignificant or even reversed. In this line, it can also be seen in our data that the Observing facet showed (nonsignificant) positive relationships with dissociation, worry, rumination, and thought suppression in the student sample, whereas in the meditating sample negative relationships with worry (significant), dissociation, and thought suppression (nonsignificant) were found. A few limitations of this study must be considered. First, a general measure of psychological symptoms and wellbeing was only included in the meditating sample. We can therefore draw no conclusions about the relationship between mindfulness and psychological well-being in our student sample. It would thus be inappropriate to carry out mediation analyses since a wide variety of meditation experience needs to be represented in the sample (therefore Baer et al. combined meditating and nonmeditating samples in their mediation analyses). Our study differs in this respect from the study of Baer et al. (2008) in which it became apparent that the Observing facet was strongly (positively) correlated with psychological well–being; however, this was only true for the meditating sample and the reverse was true for the nonmeditating sample. We cannot make this comparison in our Downloaded from asm.sagepub.com at Universiteit van Amsterdam SAGE on May 31, 2012 195 de Bruin et al. data. In addition, measures of alexithymia and rumination were only administered to the student sample and we can thus draw no conclusions about the relationship between mindfulness and these constructs in a meditating sample. Second, all our included measurements were based on predicted negative correlations with the FFMQ-NL, or mindfulness. Although, most findings were in the expected direction, we can make no inferences about convergent validity since we included no measures of related constructs with an expected positive correlation with mindfulness. Third, only self-reported measures were included and hence the magnitude of the correlations could be inflated due to shared method variance. Future validation studies might benefit from also including more objective measures, such as, for instance, neuropsychological measurements of attention (as an aspect of mindfulness), or structured interviews administered by an objective clinician, for instance, the Toronto Structured Interview for Alexithymia (Bagby, Taylor, Parker, & Dickens, 2006). Last, in our study only two samples were included. Although our samples were fairly large and psychometric properties of the FFMQ-NL could be examined for meditating as well as for nonmeditating participants, the two samples differed significantly in demographic variables (such as age), and in addition, educational level in both samples was not representative for the general population. In future studies, inclusion of a general community sample (not just college students) and a sample demographically similar to the meditating sample should be included, as was done in the study by Baer et al. (2008). In addition, the FFMQ-NL was not assessed in clinical groups in this study. From meta-analytic reviews of mindfulness-based interventions in clinical groups, it is known that most of these interventions are based on MBSR or MBCT protocols, which cover around 8 weeks. In our meditating sample, most participants had been practicing meditation for years. So although most mindfulness courses to date include an 8-week time frame, no conclusions can be drawn from this study about the possible changes in mindfulness over that time period. We are however currently administering the FFMQ-NL in a longitudinal design to several clinical groups that follow the MBSR, MBCT, or a Mindful Parenting protocol. Summarized, overall the FFMQ-NL shows favorable psychometric properties that confirm the findings of the original English language version of the FFMQ. The Dutch version of the FFMQ has good internal consistency and consists of a five-factor structure in a meditating sample and a nonmeditating sample. Meditators score higher on all facets of mindfulness compared with nonmeditators. In addition, in both samples negative correlations were found with constructs such as worry, alexithymia, rumination, thought suppression, and dissociation. The Observing facet behaved differently for participants from the meditating and the nonmeditating samples but comparable to what Baer and colleagues found. In the nonmeditating student sample, the Observing facet showed positive, instead of expected negative, associations with dissociation, worry, rumination, and thought suppression. 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