Introduction
Perfectionism has long been considered to be linked to psychological distress, with evidence that it can act as a risk or maintaining factor across psychological difficulties (Egan et al.
2011). Research with students has found that nearly two thirds can be categorised as perfectionists, with over a quarter considered maladaptive perfectionists (Grzegorek et al.
2004). Although striving for high standards is not usually problematic in itself (Shafran et al.
2002), unhealthy forms of perfectionism have been identified, sometimes known as ‘negative’ or ‘clinical’ perfectionism (Shafran and Mansell
2001). This is often associated with self-criticism, fear of failure and negative evaluation by the self or others, alongside higher levels of distress and behavioural impairments (Campbell and Paula
2002; Shafran et al.
2002; Slade and Owens
1998).
A recent cognitive behavioural model (Shafran et al.
2010) suggests that negatively biased thinking patterns and behaviours (e.g. checking, avoidance and procrastination) maintain unhealthy perfectionism. The model proposes that an individual’s self-evaluation being dependent on achievement leads them to hold inflexible standards about the level of performance they should achieve and frequently holding higher standards for themselves in comparison to others. The cognitive aspects suggested to maintain perfectionism include evaluation of how well rules are met in a dichotomous manner, self-statements incorporating ‘shoulds’ and ‘musts’, overgeneralising and selectively attending to the negative, while discounting the positive. Failure to meet these excessively demanding self-imposed standards is proposed to result in self-criticism and further counter-productive behaviours (e.g. list-making, over-preparing and being overly thorough) (Egan et al.
2014b). These responses are regarded as counter-productive because despite being aimed at helping the individual to prevent failure or to increase or maintain high standards, they can have unintended consequences which actually impair performance, such as causing tiredness or taking up time that could be used to address the full range of tasks at hand.
The cognitive behavioural model of perfectionism also suggests that standards that are met are subsequently re-appraised as not being demanding enough. There is increasing evidence consistent with this cognitive behavioural model, for example research suggests that self-critical thinking, dichotomous thinking and dysfunctional standards are characteristic of negative perfectionism (Egan et al.
2007; James et al.
2015). Experimental findings also suggest that perfectionism plays a role in standards being set high prior to performance (Egan et al.
2012), while findings have been mixed about standard setting following success or failure (Kobori et al.
2009; Egan et al.
2012).
This model of perfectionism also incorporates the role of processes involved in emotion regulation, such as worry and rumination in maintaining difficulties with perfectionism. Rumination is often defined as repetitive thinking about oneself, one’s problems and feelings of distress (Nolen-Hoeksema
1991). Much previous research has shown that rumination is associated with increased subsequent distress (Watkins
2008). Evidence suggests that perfectionists are more likely than others to ruminate and that rumination may mediate the relationship between maladaptive perfectionism and distress (Di Schiena et al.
2012; Short and Mazmanian
2013). Although any causal direction cannot be ascertained from cross-sectional studies, these findings are consistent with the possibility that rumination is one reason why perfectionist individuals tend to experience greater distress. Also in relation to emotional regulation, there is preliminary evidence that unhealthy perfectionism is associated with perfectionist attitudes towards emotions, in particular beliefs that negative emotions are unacceptable and can lead to negative reactions by others (Rimes and Chalder
2010). A cross-sectional study with university students found that unhelpful beliefs about emotions mediated the relationship between unhealthy perfectionism and emotional suppression; furthermore, emotional suppression mediated the relationship between unhealthy perfectionism and depressive symptomatology (Tran and Rimes
2017).
Another suggestion from the cognitive behavioural approach to perfectionism is that in line with the high levels of self-criticism, perfectionists tend to have low levels of self-compassion (Shafran et al.
2010). Consistent with this, Neff (
2003) found that students high in self-compassion showed lower perfectionism. Furthermore, James et al. (
2015) found that a factor on which both self-criticism and self-compassion had high loadings mediated the relationship between unhealthy perfectionism and psychological distress in a predominant student sample. Self-compassion is often seen as a key component of mindfulness and there is increasing evidence that trait mindfulness is lower in perfectionist individuals. For example, Hinterman et al. (
2012) report a significant correlation between lack of mindfulness, negative perfectionism, depression and rumination. Argus and Thompson (
2008) found that mindful awareness mediated the positive association between maladaptive perfectionism and depression severity.
Evidence to date suggests that psychological interventions, particularly cognitive behaviour therapy, targeting perfectionism-specific unhelpful thinking patterns and behaviours can be beneficial (Egan et al.
2014a,
b; Handley et al.
2015; Lloyd et al.
2014; Pleva and Wade
2007; Riley et al.
2007; Steele et al.
2013; Steele and Wade
2008). Another form of intervention which may be helpful for perfectionism is mindfulness-based cognitive therapy (MBCT), an evidence-based treatment originally developed for depressive relapse (Teasdale et al.
2000). There is evidence that MBCT addresses processes that have been identified as important in perfectionism, as described above. For example, the effect of MBCT for recurrent depression is mediated by increases in self-compassion and mindfulness (Kuyken et al.
2010). Furthermore, mindfulness approaches successfully reduce rumination (Heeren and Philippot
2011) and unhelpful beliefs about emotions (Rimes and Chalder
2010), and increase a decentered perspective on thoughts (Teasdale et al.
2002). This raises the possibility that MBCT might be an effective alternative approach to addressing perfectionism which is associated with specific unhelpful beliefs, self-critical thinking and low self-compassion, low trait mindfulness, unhelpful beliefs about the acceptability of emotions and greater rumination.
Adapting an MBCT approach for perfectionism would have the potential advantage of being based on the cognitive behavioural model of perfectionism and drawing on the associated treatment methods (both of which are associated with accumulating supporting evidence as briefly outlined above), while also drawing on additional mindfulness methods to help address processes which may act to maintain perfectionism and associated distress. As with other mindfulness-based approaches, learning how to decenter from unhelpful thinking patterns in MBCT may be helpful for perfectionist individuals to notice perfectionism-related thoughts arising without necessarily assuming that they are true or acting on them. There have been no previous studies of MBCT for perfectionism. However, there is preliminary evidence that mindfulness-based approaches may be helpful for perfectionism from a randomised study which recruited adults experiencing distress associated with perfectionism (Wimberley et al.
2016). Compared to a wait-list group, participants allocated to reading a self-help book about mindfulness for perfectionism over a 6-week period showed greater reductions in perfectionism, negative affect and stress post-intervention, with reductions maintained at 6-week follow-up.
Also exploring self-help interventions, Steele and Wade (
2008) randomised participants with bulimia nervosa to 6 weeks of guided self-help focused on either CBT for perfectionism, CBT for bulimia nervosa or a placebo condition. At post-treatment, all conditions were found to show significant improvements in symptoms of bulimia, depression and perfectionism, while at 6-month follow-up, significant differences were maintained in bulimic symptoms and perfectionism (as measured by the concern over mistakes subscale). The manual developed as the control condition drew on techniques from MBCT; however, it was not focused on perfectionism, and the authors specify that the dismantled nature of the intervention meant that it could not be classified as a mindfulness treatment (Steele and Wade
2008, p. 1317).
In this study, students experiencing perfectionism were randomly allocated to an adapted form of MBCT for clinical perfectionism or a cognitive behavioural self-help guide. This study was designed to gain information about the acceptability and feasibility of delivering a course of MBCT for perfectionist university students, and preliminary estimation of the degree of change in perfectionism associated with MBCT versus pure self-help. Pure self-help was chosen as an evidence-based minimal treatment control condition to control for the effects of receiving psycho-education and advice about the CBT approach to perfectionism; this was considered more ethical than a waiting list control condition. The primary outcome was perfectionism; secondary outcomes included impairment caused by perfectionism and self-reported depression, anxiety and stress. Exploratory analyses examined changes in self-compassion, rumination, unhelpful beliefs about emotions, mindfulness, decentering and whether these mediated group differences in changes in perfectionism.
Results
Acceptability and Engagement
Data on levels of attendance at MBCT sessions and percentage of the self-help booklet reported to be read by self-help participants are presented in Table
1. The 16 participants who completed the MBCT (attending > 80% of sessions) attended a mean of 7.2 sessions out of 8. Chi-square analyses comparing the proportion of MBCT and self-help participants who completed ≥ 80% of the intervention suggested that there were no significant between-group differences (
χ
2((1) = 0.3,
p = .595).
The mean total duration of weekly formal practice over MBCT, reported at post-treatment, was 109 min (SD = 46.7). The mean number of days of formal home meditation practice per week between MBCT sessions was 3.8 (SD = 1.3). For the 24 MBCT participants for whom data was available, 14 (58.3%) participants reported reading at least 80% of session hand-outs. Remaining participants reported reading 70% (n = 2), 60% (n = 1), 30% (n = 1), 20% (n = 2) and 10% (n = 3). One participant completed post-intervention questionnaires but did not answer these questions relating to home practice. For the self-help group, 16 participants reported that the number of exercises completed ranged from one to nine (mean = 4.4, S.D. = 2.5). Three participants did not answer these questions.
Perceived Usefulness of the Interventions
All MBCT completers rated the course as useful, with 50% rating it as ‘very useful’ (see Table
1). Chi-square analyses (comparing those rating each intervention as either ‘no use at all’, ‘quite useful’ or ‘useful’ with those rating it as ‘moderately useful’ or ‘very useful’) showed that there were no significant between-group differences in the usefulness ratings for those who completed the interventions (
χ
2((1) = 3.4,
p = .067). However, there were significant group differences, favouring MBCT, when including participants who did not complete the intervention (
χ
2(1) = 6.7,
p = .010).
Group Differences at Post-Treatment
ITT ANCOVAs found significantly lower post-treatment COM, PS, clinical perfectionism and stress in the MBCT than in the self-help group, covarying for baseline scores. There were no significant group differences in impairment in daily life, anxiety or depression. ANCOVAs with process measures showed that the MBCT group had significantly lower levels of unhelpful beliefs about emotions and rumination, and higher levels of mindfulness, self-compassion and decentering at post-treatment, in comparison with the self-help group. See Table
2 for means and standard deviations at each assessment point, and results of all ANCOVAs in Table
3.
Table 2
Pre, post and follow-up mean scores for MBCT and self-help group
Intention-to-treat—clinical outcomes |
Concern over mistakes | 33.9 (5.8) | 27.2 (7.2) | 26.8 (7.9) | 31.4 (6.4) | 28.4 (7.2) | 29.6 (7.3) |
Clinical perfectionism | 29.4 (4.7) | 25.8 (4.8) | 25.4 (4.3) | 29.0 (5.1) | 27.4 (5.2) | 28.0 (5.6) |
Personal standards | 30.0 (3.3) | 26.9 (4.8) | 26.2 (5.2) | 29.3 (3.7) | 28.4 (4.1) | 28.6 (4.3) |
Daily impairment by perfectionism | 19.6 (8.3) | 16.1 (9.6) | 15.6 (9.6) | 17.2 (7.7) | 16.3 (8.4) | 18.2 (9.9) |
Anxiety | 12.9 (9.0) | 10.4 (9.6) | 10.1 (7.7) | 13.4 (10.5) | 12.1 (9.8) | 11.8 (9.6) |
Depression | 16.1 (12.1) | 12.1 (12.6) | 13.2 (11.5) | 14.0 (10.3) | 11.6 (9.7) | 13.4 (11.1) |
Stress | 24.0 (10.2) | 17.5 (11.4) | 18.8 (10.8) | 21.6 (9.6) | 20.3 (9.9) | 21.1 (9.4) |
Process measures
|
Beliefs about emotions | 47.7 (13.0) | 39.2 (17.3) | 38.7 (14.7) | 49.5 (12.2) | 46.8 (13.7) | 49.7 (12.5) |
Decentering | 26.0 (6.7) | 36.1 (8.4) | 34.1 (8.0) | 29.4 (5.3) | 30.9 (5.8) | 30.8 (5.4) |
Rumination | 35.2 (4.5) | 29.2 (6.5) | 30.2 (5.9) | 33.7 (5.6) | 32.7 (6.1) | 32.7 (6.8) |
Mindfulness | 104.8 (18.4) | 119.5 (19.9) | 119.5 (22.9) | 109.3 (17.1) | 111.0 (14.5) | 111.6 (14.8) |
Self-compassion | 2.0 (0.5) | 2.7 (0.7) | 2.7 (0.8) | 2.3 (0.5) | 2.4 (0.5) | 2.5 (0.7) |
Table 3
Results of ANCOVA investigating between-group differences, adjusting for pre-treatment questionnaire scores
Intention-to-treat—clinical outcomes |
Concern over mistakes | − 3.18 | 4.8* | 0.08 | 0.00 | 0.19 | − 4.27 | 5.7* | 0.09 | 0.01 | 0.22 |
Clinical perfectionism | − 2.00 | 4.3* | 0.69 | 0.00 | 0.20 | − 2.82 | 6.3* | 0.10 | 0.01 | 0.23 |
Personal standards | − 2.12 | 6.4* | 0.10 | 0.01 | 0.23 | − 3.06 | 10.5** | 0.16 | 0.04 | 0.29 |
Daily impairment by perfectionism | − 2.21 | _2.0 | 0.03 | 0.00 | 0.14 | − 4.49 | 5.2* | 0.08 | 0.01 | 0.21 |
Anxiety | − 1.32 | _0.6 | 0.01 | 0.00 | 0.09 | − 1.45 | _0.7 | 0.01 | 0.00 | 0.09 |
Depression | − 1.22 | _0.5 | 0.01 | 0.00 | 0.08 | − 1.57 | _0.5 | 0.01 | 0.00 | 0.09 |
Stress | − 4.51 | 4.8* | 0.08 | 0.00 | 0.20 | − 3.25 | _1.8 | 0.03 | 0.00 | 0.13 |
Process measures
|
Beliefs about emotions | − 10.35 | 10.1** | 0.15 | 0.03 | 0.29 | − 10.08 | 10.5** | 0.16 | 0.04 | 0.30 |
Decentering | 6.66 | 13.3** | 0.19 | 0.06 | 0.33 | 4.36 | 6.1* | 0.10 | 0.01 | 0.23 |
Rumination | − 4.73 | 16.5** | 0.24 | 0.08 | 0.36 | − 4.83 | 5.5* | 0.09 | 0.01 | 0.22 |
Mindfulness | 11.93 | 16.5** | 0.22 | 0.08 | 0.36 | 10.92 | 7.6* | 0.12 | 0.02 | 0.25 |
Self-compassion | 0.42 | 8.6** | 0.13 | 0.02 | 0.27 | 0.37 | _3.9 | 0.06 | 0.00 | 0.18 |
Group Differences at 10-Week Follow-Up
ITT ANCOVAs found significantly lower post-treatment COM, PS, clinical perfectionism, and impairment in daily life in the MBCT than in the self-help group, covarying for baseline scores. There were no significant group differences in stress, anxiety, depression or self-compassion. The MBCT group had significantly lower levels of unhelpful beliefs about emotions and rumination, and higher levels of mindfulness, and decentering, in comparison with the self-help group.
Analyses for those participants who fulfilled the study requirements of attending ≥ 80% of MBCT sessions or reported reading ≥ 80% of the self-help guide were also examined. Due to small sample sizes at both post-treatment (MBCT
n = 16; self-help
n = 13) and 10-week follow-up (MBCT
n = 16; self-help
n = 9), these analyses are included as
supplementary material.
Relationship Between MBCT Home Practice and Change in Psychological Variables
Pearson’s correlations showed that greater frequency of home practice per week was significantly correlated with larger increases in self-compassion (r(17) = 0.51, p = 0.04). Frequency of home practice was not significantly correlated with changes in other outcome or process measures (all r < 0.25).
Reliable and Clinically Significant Change
The extent of change on the COM, clinical perfectionism and DASS-21 subscales was calculated using Jacobson and Truax’s (
1991) criteria for reliable and clinically significant change. For COM, non-clinical normative data was drawn from an adult sample (
n = 255) (Harvey et al.
2004) and clinical normative values from Steele et al. (
2013). These values led to an RCI cut-off of 20.9, with a reliability coefficient of .88, as reported in Frost et al. (
1990). For clinical perfectionism calculations, normative data was drawn from a community sample by Chang and Sanna (
2012) (
n = 243) and clinical normative values from Riley et al. (
2007) (
n = 20). On the basis of these values, the RCI cut-off was calculated as 30.59, with a reliability coefficient of .83, as reported by Chang and Sanna. For the DASS subscales, non-clinical normative values from an adult sample (
n = 497) (Crawford et al.
2011) and clinical normative values from a sample of outpatients with depression and/or anxiety (
n = 258) (Antony et al.
1998) were utilised. This led to cut-off values for clinically significant change of depression = 7.82, anxiety = 4.04 and stress = 7.59. Henry and Crawford’s reliability coefficients for each DASS subscale were adopted: depression = .88, anxiety = .82 and stress = .90. Thomas and Truax’s (
2008) recommended categories of change were then used: recovered (reliable and clinically significant change), improved (reliable change without significant clinical change), same (no change) and deteriorated (reliable change with worsening symptoms). See Table
4.
Table 4
Number of participants meeting criterion for change in intention-to-treat sample
Post-treatment |
(MBCT = 28; Self-help = 32) |
Concern over mistakes* | 6 (21) | 12 (43) | 10 (36) | 0 (0) | 4 (13) | 8 (25) | 20 (63) | 0 (0) |
Clinical perfectionism | 8 (29) | 0 (0) | 20 (71) | 0 (0) | 4 (13) | 0 (0) | 28 (88) | 0 (0) |
DASS depression* | 10 (36) | 4 (14) | 11 (39) | 3 (11) | 3 (9) | 5 (16) | 22 (69) | 2 (6) |
DASS anxiety | 3 (11) | 3 (11) | 22 (79) | 0 (0) | 3 (9) | 2 (6) | 26 (81) | 1 (3) |
DASS stress* | 5 (18) | 10 (36) | 10 (36) | 3 (11) | 3 (9) | 3 (9) | 24 (75) | 2 (6) |
10-week follow-up |
Concern over mistakes | 5 (18) | 11 (39) | 12 (43) | 0 (0) | 1 (3) | 0 (0) | 18 (56) | 4 (13) |
Clinical perfectionism* | 10 (36) | 0 (0) | 18 (64) | 0 (0) | 4 (13) | 0 (0) | 27 (84) | 1 (3) |
DASS depression | 7 (25) | 5 (18) | 12 (43) | 4 (14) | 6 (19) | 3 (9) | 18 (56) | 5 (16) |
DASS anxiety | 3 (11) | 5 (18) | 18 (64) | 2 (7) | 3 (9) | 4 (13) | 22 (69) | 3 (9) |
DASS stress* | 3 (11) | 9 (32) | 14 (50) | 2 (7) | 0 (0) | 6 (19) | 22 (69) | 4 (13) |
Chi-square analyses were undertaken to compare the two groups with regard to reliable change (i.e. ‘improved or recovered’ versus ‘same or deteriorated’). If more than 20% of the cells had an expected cell count of less than five, Fisher’s exact tests were undertaken instead. At post-treatment, a greater proportion of the MBCT group than the self-help group had shown reliable change on the COM, DASS depression and DASS stress (p values < 0.05); there was no group difference for clinical perfectionism or DASS anxiety. At 10-week follow-up, relative to pre-treatment scores, a greater proportion of the MBCT group than the self-help group showed benefits in clinical perfectionism and DASS stress (all p values < 0.05) but there were no significant group differences for COM, DASS anxiety or depression.
Mechanisms of Change
As significant differences were observed across all process measures between pre- and post-intervention, mediational analysis assessed whether changes in perfectionism were due to changes in these hypothesised mechanisms. The bootstrapping method was used to investigate mediation, as advocated by Preacher and Hayes (
2008). With this approach, mediation is investigated by directly testing the significance of the indirect effects of the independent variable (IV) on the dependent variable (DV) through a mediator (M). Bootstrapping is a nonparametric resampling procedure that involves repeatedly sampling from the data set and estimating the indirect effect in each resampled data set. By repeating this process 5000 times, 95% confidence intervals are constructed for the indirect effect. This method allows multiple mediators to be investigated, indicating the individual effects of each mediator, controlling for the other. Indirect effects were considered significant when the bias-corrected and accelerated confidence intervals did not include zero.
Mediation was investigated by deriving 95% CI for the indirect effect of group (MBCT versus self-help) via the hypothesised mediators (change in mindfulness, self-compassion, unhelpful beliefs about emotions, decentering and rumination from pre- to post-intervention) on change in COM and clinical perfectionism. Separate mediation models were run for the two perfectionism measures; see Table
5. Results indicated that change in self-compassion significantly mediated the relationship between group (MBCT versus self-help) and changes in clinical perfectionism scores.
Table 5
Summary of multiple mediator model (5000 bootstraps) for changes in COM and clinical perfectionism from pre- to post-intervention
Group | Decentering | COM | − 8.73 | .0000 | 0.07 | .703 | − 1.0126 | .021 | − 0.6208 | .687 | − 4.11 | 2.67 | 6.19 | .021 |
| Rumination | | 4.9 | .0001 | 0.26 | .459 | | | 1.281 | .439 | − 3.13 | 5.95 | | |
| Mindfulness | | − 13.13 | .0001 | − 0.09 | .460 | | | 1.209 | .440 | − 3.10 | 4.74 | | |
| Self-compassion | | − 0.53 | .0006 | − 6.57 | .017 | | | 3.505 | .034 | − 0.12 | 9.28 | | |
| Beliefs about | | | | | | | | | | | | | |
| emotions | | 8.29 | .0042 | 0.22 | .058 | | | 1.828 | .091 | − 0.03 | 4.90 | | |
Group | Decentering | Clinical | − 8.73 | .0000 | 0.05 | .484 | 0.09 | .933 | − 0.58 | .384 | − 2.82 | 0.99 | 2.15 | .044 |
| Rumination | perfectionism | 4.9 | .0001 | − 0.01 | .950 | | | − 0.05 | .947 | − 2.01 | 1.72 | | |
| Mindfulness | | − 13.13 | .0001 | − 0.04 | .413 | | | 0.44 | .506 | − 1.60 | 2.56 | | |
| Self-compassion | | − 0.53 | .0006 | − 3.79 | .002 | | | 1.98 | .012 | 0.27 | 4.35 | | |
| Beliefs about | | | | | | | | | | | | | |
| emotions | | 8.29 | .0042 | 0.04 | .429 | | | 0.26 | .014 | 1.44 | 1.44 | | |
Discussion
We compared the acceptability and impact of an adapted MBCT intervention with a minimal treatment control condition (a self-help CBT psycho-educational guide) in students experiencing difficulties due to perfectionism. MBCT participants had significantly lower levels of perfectionism (concern over mistakes and personal standards), clinical perfectionism and stress at post-treatment than self-help participants, adjusting for baseline levels. These benefits in perfectionism were maintained at 10-week follow-up, at which point the MBCT group also had lower levels impairment caused by perfectionism than the self-help group. Similarly, a greater proportion of MBCT than self-help participants showed reliable change in perfectionism at post-treatment and clinical perfectionism at follow-up.
Overall, these findings suggest that the adapted MBCT shows promise as an intervention for those experiencing difficulties related to perfectionism and is more beneficial than a pure CBT self-help guide. The degree of change in the perfectionism measures is not as large as in individual CBT for perfectionism (e.g. CPQ
d = 1.31 (Riley et al.
2007); COM
d = 1.23 and PS
d = 0.77 (Egan et al.
2014a,
b)). However, the confidence intervals around the mean group differences in the current study are relatively large due to the small sample size. Therefore, it is possible that future research using a larger sample that allowed more precise estimates may find larger effect sizes.
At post-treatment, a greater proportion of the MBCT group than the self-help group had shown reliable change on the DASS depression and DASS stress, although there was no group difference for DASS anxiety. This mindfulness intervention had additional benefits such as reductions in unhelpful beliefs about emotions, decentering and improvements in self-compassion and mindfulness which are not typically reported in CBT intervention studies and which may have wider benefits for participants beyond their perfectionism. Furthermore, mindfulness training is currently generally popular and may be perceived by students experiencing perfectionism as being more attractive and potentially less stigmatising than attending therapy. This is particularly important as individuals experiencing difficulties with perfectionism do not typically present at clinical services seeking help for their perfectionism. The intervention is provided in a group setting, which, alongside Handley et al.’s (
2015) recent trial of group CBT for perfectionism, highlights the importance of interventions that require fewer therapist resources than those provided on an individual basis. Furthermore, in many locations, mindfulness or meditation groups are available to the general public which can provide support for an ongoing mindfulness practice. This may be important for maintenance of gains.
Potential mechanisms of change were also investigated, with analyses suggesting that the MBCT group had significantly lower levels of unhelpful beliefs about emotions and rumination, and higher levels of mindfulness, self-compassion and decentering at post-treatment, in comparison with the self-help group. Of these processes, there was evidence that self-compassion was particularly important, as changes in this process were found to mediate the effect of MBCT (versus self-help) on clinical perfectionism. This is consistent with evidence of self-compassion as a mediator in MBCT for recurrent depression (Kuyken et al.
2010). However, it should be noted that mediation analyses should preferably include a mediator measured at a time point between the independent and dependent variables, so these analyses should only be regarded as exploratory. Future studies should investigate self-compassion further as a potential mediator and could also investigate whether greater emphasis on self-compassion would improve the treatment effect sizes.
Treatment completion for the MBCT was moderately good. Of those randomised to MBCT, 59% completed the course and displayed high rates of session attendance and homework completion. Those who did not complete MBCT primarily suggested that finding the time to commit to it was difficult, with many acknowledging that this was related to their perfectionism. This is consistent with evidence that despite identifying many negative consequences of perfectionism, individuals reported numerous benefits and often prefer not to change their perfectionism (Egan et al.
2013). Although MBCT required attendance at eight 2-hour sessions and daily practice, treatment engagement was better than in the self-help group, with only 13 of the 33 self-help participants reporting that they had read at least 80% of the self-help guide. While this was not statistically different, this could be a power issue. The MBCT participants may have been willing to remain engaged despite the greater time involved because of the higher perceived usefulness or early impact of this intervention compared to the self-help.
Limitations of the study include drop-outs—only 72% of participants completed pre- and post-intervention assessments. No significant differences in baseline characteristics between those who remained in the study or dropped out were found. Drop-out rates should be considered in future studies as this may affect statistical power and limit generalizability. The use of LOCF as a way to manage missing data may have introduced bias into the results and resulted in confidence intervals that are too narrow (Altman
2009), therefore per protocol analyses have also been provided as
supplementary information. Participants were considered to be intervention completers if they attended at least 80% of the MBCT sessions but this is an arbitrary cut-off, and future studies could investigate the impact of a lower treatment dose, such as 50%. In addition, the psycho-educational condition was developed specifically for this study, as resources were not available to provide participants with a previously evaluated self-help book, and the follow-up time period was relatively short (10 weeks).
A strength of the study was the comparison of MBCT with an active control group (pure CBT self-help). However, as MBCT was a face-to-face group intervention, non-specific factors, such as therapist and social support or learning from the contributions of other participants, may have influenced the results. Similarly, the current study was not designed to test whether the mindfulness components of the new intervention were the reason for any differences between the two groups. A future study could compare the MBCT programme with a CBT intervention matched for both CBT content and non-specific factors. Supported self-help would be an alternative cost-effective control condition which might help match the two groups for levels of participant engagement.
In conclusion, this study suggests that MBCT shows promise as an intervention for students experiencing difficulties as a result of perfectionism. MBCT for perfectionism needs investigation in larger-scale studies. Further research could also compare MBCT and group-based CBT for perfectionism in terms of recruitment, acceptability, feasibility and effectiveness. Importantly, given the findings related to the role of self-compassion, future studies should also further investigate how change in this variable is most effectively achieved and the impact this has on levels of perfectionism and its associated psychological difficulties.