Personality and Individual Differences 54 (2013) 426–431

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Personality and Individual Differences

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Examining the relationship of perfectionism, depression, and optimism: Testingfor mediation and moderation

Jessica Black ⇑, William M. ReynoldsHumboldt State University, 1 Harpst Street, Arcata, CA 95521, United States

a r t i c l e i n f o

Article history:Received 6 August 2012Received in revised form 10 October 2012Accepted 18 October 2012Available online 13 November 2012

Keywords:PerfectionismOptimismDepressionMediation

0191-8869/$ - see front matter � 2012 Elsevier Ltd. Ahttp://dx.doi.org/10.1016/j.paid.2012.10.012

⇑ Corresponding author. Address: 329 Bayside RdStates. Tel.: +1 707 633 5362.

E-mail address: jeb130@humboldt.edu (J. Black).

a b s t r a c t

The present study investigated the relationship between perfectionism and depression, and the media-tion/moderation effects of optimism. Participants were126 adults (78% women, mean age = 27 years)who completed an online survey that included the Multidimensional Perfectionism Scale (Frost, Marten,Lahart, & Rosenblate, 1990), the Revised Life Orientation Test (Scheier, Carver, & Bridges, 1994), and theHamilton Depression Inventory (Reynolds & Kobak, 1995). Maladaptive, adaptive and total perfectionismwere examined in separate analyses. In most analyses, the data fit a mediation model. Optimism limitedthe effect (relationship) of total and maladaptive perfectionism on depression. Adaptive perfectionismwas related to depression only through optimism. There was a small gender difference, with indirecteffects greater for men. These results are consistent with past research and support the notion that cor-relations between perfectionism, as a trait, and affective variables must be examined using multivariatemodels that allow for the determination of complex relationships.

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1. Introduction

Perfectionism has been generally understood to be associatedwith negative psychological outcomes (Frost et al., 1990; Hewitt,Flett, Turnbull-Donovan, & Mikail, 1991), although some degreeof pursuit of excellence is a necessary component of achievement.Beginning with Hamachek (1978), researchers have sought to iden-tify correlates of perfectionism (Slade & Owens, 1998). Hamachekdistinguished between normal and neurotic perfectionism in termsof satisfaction and control: the normal perfectionist derives plea-sure from striving for perfection yet knows when to relax stan-dards, while the neurotic perfectionist is driven by fear of failure.Slade and Owens (1998) defined what they called a ‘‘dual-processmodel of positive and negative perfectionism,’’ according to whichpositive perfectionism and negative perfectionism can be ex-plained in terms of striving and trying to avoid undesirable results.

In a meta-analysis of 15 studies that had used a dualist ap-proach, Stoeber and Otto (2006) concluded that striving was a po-sitive form of perfectionism. They contrasted it with perfectionistconcerns, such as an inability to live up to perceived expectations.Research by Stoeber, Uphill, and Hotham (2009) partially clarifiedthe connection between striving and outcome: triathlon partici-pants who scored high on perfectionism and reported high

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., Arcata, CA 95521, United

achievement goals performed better in their races than those withlow achievement goals. Stoeber et al. found that differences be-tween performance approach and avoidance mediated the perfec-tionism–performance relationship.

Researchers have found that correlates of perfectionism are of-ten mediated by other variables. Harris, Pepper, and Maack (2008)used the Multidimensional Perfectionism Scale by Frost and col-leagues (MPS; 1990) to examine rumination as a mediator betweenmaladaptive perfectionism and depression. The MPS was designedwith six factors; ‘‘personal standards’’ has been used to assess po-sitive perfectionism, while ‘‘concern over mistakes’’ and ‘‘doubtsabout actions’’ together can reflect negative perfectionism (cf. Har-ris et al., 2008; Park, Heppner, & Lee, 2010; Sturman, Flett, Hewitt,& Rudolph, 2009). Harris et al. found that rumination mediated therelationship between maladaptive perfectionism and depression,using the MPS subscales of concern over mistakes and doubtsabout actions. Park et al. (2010) used the same MPS subscales asa measure of maladaptive perfectionism and found that maladap-tive coping mediated the relationship between maladaptive per-fectionism and distress. This was especially true for men, forwhom coping increased more strongly with greater perfectionismthan it did for women.

Ashby, Dickinson, Gnilka, and Noble (2011) reported that hopemediated the relationship between maladaptive perfectionism anddepression in middle school students. Adaptive perfectionism wasnot significantly correlated to depression, and although it was notconsidered a mediator, it did lend itself to a statistically significantindirect effects model, as determined by bootstrapping techniques.

J. Black, W.M. Reynolds / Personality and Individual Differences 54 (2013) 426–431 427

Ashby et al. also tested a moderation model, but found that it didnot fit their data on perfectionism, hope, and depression.

Hope is closely related to optimism, which is often predictive ofpositive psychological outcomes (Peterson, 2000). Optimism ap-pears related to perfectionism in that the belief that high goalscan be attained is part of seeking their attainment. Peterson pro-posed two dimensions of optimism, big and little. He associatedbig optimism with what Scheier and Carver (1992) call disposi-tional optimism, which their scale, the Revised Life OrientationTest (R-LOT; Scheier et al., 1994), measures. Chang, Chang, andSanna (2009) outline the complexities of optimism, suggesting thatit may have realistic (adaptive) and unrealistic (maladaptive)dimensions.

Both optimism and perfectionism have been connected withstriving, hope, and depression. Fry and Debats (2009), in a studyof predictors of mortality in older adults found perfectionism asso-ciated with increased risk of death and dispositional optimismwith decreased mortality. Other research (e.g. Bergman, Nyland,& Burns, 2007) implies that adaptive optimism should facilitatestriving, encouraging perfectionists to focus on the possibility ofachieving excellence rather than on the need to avoid censure forfailing to do so. Chang (2009) reported that positive performanceperfectionism meant more optimism (r(244) = .22), while negativeperformance perfectionism meant less optimism (r(244) = �.26).We did not, however, find any mediational analysis of the relation-ship between perfectionism and optimism in the literature.

Baron and Kenny (1986) define moderation and mediationmodels used to test ways in which the relationship between twovariables can be affected by third variables. Moderation wouldindicate an interaction between the independent variable, in thiscase perfectionism, and the moderator, optimism. Mediation oc-curs when the relationship between the independent variableand the dependent variable is different when a third variable is in-cluded in the model. According to the Baron and Kenny criteria, thedirect relationship between two variables, significant when con-sidered alone, approaches zero when measured in the presenceof the mediator. An indirect effect can occur even when there isno direct effect (Preacher & Hayes, 2004). In this case, the relation-ship between independent and dependent variables depends en-tirely upon the mediator. The measurement of mediation andindirect effects allows some inference of causation, as the indepen-dent variable is assumed to cause the mediator, which in turn af-fects the dependent variable. A moderator, on the other hand,exists independently of the focal predictor, which varies at differ-ent levels of the moderator.

The current research investigated the degree to which optimismacts as a mediator and/or moderator of the relationship betweenperfectionism and depressive symptomatology. Because of the pos-sible dual nature of optimism (Chang et al., 2009), we predicted amoderation model. Flett, Blankstein, Hewitt, and Koledin (1992)found gender differences in the correlations between perfection-ism and procrastination. In view of Park et al.’s (2010) similar re-sults in a mediation model, we examined potential genderdifferences in our sample by testing separate models for womenand men. We used maladaptive and adaptive perfectionism do-mains as well as overall perfectionism. Our goal was to betterunderstand the potential role of optimism in the relationship be-tween perfectionism and depression.

2. Method

2.1. Participants

Participants were 126 adults (98 women, 28 men) with a meanage of 27.7 (SD = 13.9). Of these participants, 57 were students who

completed an online survey through the Psychology DepartmentResearch Pool, and 69 were adults who completed the same ques-tionnaire using Survey Monkey.

2.2. Instrumentation

The Multidimensional Perfectionism Scale (Frost et al., 1990) isa 35-item questionnaire intended to reflect six aspects underlyingthe construct. It is considered a reliable measure of general perfec-tionism (Chang, 2000). In the current investigation the 6-itemorganization subscale was omitted, resulting in a 29-item scalewith an internal consistency reliability of ra = .88. Consistent withprevious research (Kawamura, Hunt, Frost, & DiBartolo, 2001;Sturman et al., 2009) we used the concern over mistakes anddoubts about actions subscales as a measure of maladaptiveperfectionism (ra = .84) and the Personal Standards subscale torepresent adaptive perfectionism (ra = .76).

The Revised Life Orientation Test (Scheier et al., 1994) was usedto assess optimism; its test–retest reliability has proven moder-ately high (.79 at 28 months), and it has shown acceptable internalconsistency. Of the ten statements evaluated on a zero-to-fourpoint scale, three are reverse-coded and four are fillers (ra = .77for this study).

The Hamilton Depression Inventory (HDI; Reynolds & Kobak,1995) was developed to provide a paper–pencil analog measureto the Hamilton Depression Rating Scale (Hamilton, 1960, 1967)clinical interview. Reynolds and Kobak provided strong evidencefor the reliability and validity of three versions of the HDI basedon clinical and nonclinical samples. The HDI Short Form, whichconsists of 15 items, was used in the current study. Reynolds andKobak reported an internal consistency of .93 for the HDI ShortForm in a mixed clinical and nonclinical sample of 357 adults. Inthe current study ra = .91.

2.3. Procedure

An anonymous survey was conducted online through the HSUPsychology Department Research Pool and through Survey Monkeyfor a total of 2 months. Links to the survey were sent in emails andposted on social networking sites. Participants’ identities were pro-tected by disabling IP address and email tracking features on Sur-vey Monkey. No reward was offered other than class creditavailable to students responding through the psychology depart-ment participation pool; participants were allowed to withdrawat any time without losing credit.

2.4. Data analysis

The criteria outlined by Baron and Kenny (1986) provide a con-ceptual framework to facilitate examination of mediation, but doesnot include a test of statistical significance for the indirect effect ofthe mediator (a � b; see Fig. 1). Baron and Kenny suggested the So-bel (1982) test as appropriate: it tests the null hypothesis that theindirect effect is zero. However, the Sobel test assumes the distri-bution of ab is normal, which is seldom the case (Hayes, 2009).Bootstrapping, or the nonparametric resampling of the data setin order to make repeated estimates, makes no such assumptions(Preacher & Hayes, 2008). We present regression statistics as wellas results of the Sobel test. We also used bootstrapping (10,000 res-amples) to provide bias corrected and accelerated confidence inter-vals as a test of statistical significance.

Following the recommendations of Preacher and Kelley (2011),we present kappa squared, j2, as an effect size that is both stan-dardized and insensitive to sample size. j2 is the ratio of the indi-rect effect to the maximum indirect possible given the constraintsof the design and data. The problem of determining when an effect

Fig. 1. The unmediated path between independent and dependent variables (c) ispresented above. Below, optimism is added, resulting in a simple mediationdiagram. The indirect effect is c–c0 , or a � b.In both cases, as perfectionism increases,so does depression, but when optimism works as a mediator, the relationship isless.

Table 1Pearson correlation coefficients between total perfectionism and adaptive andmaladaptive dimensions, optimism, depression, and age (N = 126).

1 2 3 4 5

1. Total perfectionism –2. Maladaptive

perfectionism.861*** –

3. Adaptive perfectionism .590*** .327*** –4. Optimism �.302** �.454*** .154 –5. Depression .364*** .521*** �.037 �.556*** –6. Age �.011 �.130 .002 .086 �.154

** p < .01.*** p < .001.

428 J. Black, W.M. Reynolds / Personality and Individual Differences 54 (2013) 426–431

can be considered large is addressed by Preacher and Kelley withreference to Cohen’s (1988) estimates for squared correlation coef-ficients: .01, .09, and .25 can be considered small, medium, andlarge respectively. In addition to j2, we also provide the percentof the total effect that is mediated, PM (Table 3 provides completemediation results). Effect sizes and confidence intervals were gen-erated using MBESS, an R package (Kelley & Lai, 2010).

3. Results

Preliminary analyses showed that scores on the MPS and LOTRwere normally distributed and scores on the HDI were not: Asquare root transformation of the HDI data fully corrected skewand kurtosis problems. Total perfectionism scores were negativelycorrelated with optimism, r(124) = �.30, 95% C.I.[�.46, �.13], and

Table 2Means (standard deviations) for total perfectionism (MPS), maladaptive perfectionism (M

MPS MP

Total 78.6 (14.4) 32.0(7Women 78.3 (14.1) 31.8(7Men 79.8 (15.5) 32.6(8Cohen’s d – men vs. women �0.10 �0.10t 0.48 0.49p .63 .62HSU students 79.0 (16.2) 32.5(8Survey Monkey 78.3 (12.7) 32.0(7Cohen’s d – HSU vs. Survey Monkey 0.05 0.06t 0.26 0.62p .70 .54

* Untransformed data used for HDI.

positively correlated with depression, r(124) = .36, 95% C.I.[.21,.50], thus not supporting the test of a moderation model. Depres-sion was negatively correlated with optimism, r(124) = �.56, 95%C.I.[�.68, �.40]. Age demonstrated a very low, nonsignificant cor-relation with perfectionism, r(124) = �.01, 95% C.I.[�.17, .15], andoptimism scores, r(126) = .09, 95% C.I.[�.06, .24], and a low nega-tive correlation with depression, r(124) = �.15, 95% C.I.[�.30,�.01]. Table 1 provides correlations between all scales.

Tests of independent means for gender showed statisticallynonsignificant differences on total perfectionism, maladaptive per-fectionism, adaptive perfectionism, and depression. There was agender difference in optimism with women (M = 15.8, SD = 3.7)more optimistic than men (M = 14.1, SD = 4.2), t(124) = 2.15,p = .03, d = 0.45. There were no significant differences in means be-tween data collection samples (HSU students versus Survey Mon-key; see Table 2).

3.1. Mediation

Age was initially entered as a covariate in the mediation model.Because it did not have a significant effect, it was thereafter ex-cluded in order to facilitate interpretation and calculation of effectsizes.

3.1.1. Total perfectionismOptimism mediated the effect of perfectionism on depression,

with an estimated indirect effect (ab) = 0.014, j2 = .174 (see Table 3for confidence intervals). For women there was a smaller effect,ab = 0.008, j2 = .112. For men the effect was larger, ab = 0.031,j2 = .358, and the data fit a full mediation model (Baron & Kenny,1986). Data from the two subsamples, Survey Monkey and the uni-versity research pool (HSU), were also tested as two separate mod-els; in both cases significant results ensued (respectively,ab = 0.010, j2 = .106, and ab = 0.015, j2 = .219).

3.1.2. Maladaptive perfectionismOptimism mediated the relationship between maladaptive per-

fectionism and depression, ab = 0.029, j2 = .203. As before, for men,optimism fully mediated maladaptive perfectionism, ab = 0.076,j2 = .431. For women the effect was smaller, ab = 0.018, j2 = .141.

3.1.3. Adaptive perfectionismAlthough the adaptive perfectionism subscale was not signifi-

cantly correlated with depression, it was positively correlated tooptimism, and the possibility of an indirect effect remained (Hayes,2009). Results of mediation analyses confirmed an indirect effect,ab = �.027, j2 = .118. As adaptive perfectionism rose, so did opti-mism, which related to a decrease in depression (see Fig. 2). Whentested separately by gender there was again a difference: In this

P), adaptive perfectionism (AP), optimism (LOTR), and depression (HDI).

AP LOTR HDI*

.9) 23.7(4.5) 15.4 (3.8) 9.8(7.9)

.7) 23.5(4.3) 15.8 (3.7) 9.6 (6.9)

.8) 24.5(5.2) 14.1 (4.2) 10.4 (10.9)�0.22 0.45 �0.100.97 �2.15 0.47.33 .03 .64

.9) 23.6(4.8) 15.3 (4.3) 11.1 (8.1)

.0) 23.8(4.3) 15.6 (3.4) 8.6 (7.7)�0.04 �0.08 0.32�0.18 �0.39 1.78.86 .70 .08

Table 3Mediation Results.

Variable ab 95% C.I. a b c c’ Sobel test PM 95% C.I. j2 95% C.I.

LL UL z p LL UL LL UL

Total perfectionism 0.014 0.006 0.024 �0.09* �0.15* 0.03* 0.02* 3.07 .002 0.44 0.19 0.81 .174 .075 .281Women 0.008 0.002 0.018 �0.07* �0.12* 0.03* 0.02* 2.23 .026 0.27 0.06 0.64 .112 .025 .231Men 0.031 0.011 0.058 �0.12* �0.27* 0.03 <0.01 2.15 .032 1.03 0.39 4.94 .358 .131 .563

Maladaptive perfectionism 0.029 0.013 0.049 �0.24* �0.12* 0.08* 0.05* 3.77 <.001 0.37 0.17 0.63 .203 .104 .310Women 0.018 0.005 0.037 �0.19* �0.10* 0.08* 0.06* 2.74 .006 0.24 0.07 0.50 .141 .048 .260Men 0.076 0.039 0.140 �0.30* �0.26* 0.08* 0.01 2.91 .004 0.90 0.45 1.98 .431 .231 .625

Adaptive perfectionism �0.027 �0.057 �0.001 0.16* �0.17* �0.01 0.01 �1.68 .094 1.94 0.63 2450 .118 .015 .224Women �0.033 �0.067 �0.011 0.22* �0.15* �0.01 0.03 �2.33 .020 4.67 1.77 3851 .144 .054 .262Men 0.008 �0.087 0.087 �0.03 �0.27* �0.02 �0.02 0.184 .854 �0.51 �35.6 5.40 .045 .000 .135

ab = estimated indirect effect. All confidence intervals generated with bias corrected and accelerated bootstrapping(N = 10,000).* p < .05.

Fig. 2. The indirect effect of adaptive perfectionism on depression is throughoptimism.

J. Black, W.M. Reynolds / Personality and Individual Differences 54 (2013) 426–431 429

case, the indirect effect was significant for women, ab = �.033,j2 = .144, but not for men.

4. Discussion

Perfectionists set high standards for themselves, and the failureto meet these standards often relates to poor psychological out-comes. For persons who manifest strong perfectionistic tendencies,the perception or anticipation of failure could lead to feelings ofdepression. Perfectionists who have a belief in their ability toachieve their goals should be less likely to experience the samenegative consequences. In this manner, optimism should reducethe negative affective consequences of perfectionism. Initially, weexpected a moderation model, with persons scoring high on per-fectionism and low on optimism reporting greater depression,but persons high on optimism showing less negative outcomes.The current research found a more complex mediation relationshipto fit the data.

In all the mediation models we tested, with the exception ofadaptive perfectionism in men, there was a significant indirect ef-fect. Kappa squared values indicate medium to large effect sizes.For our sample, effects were larger for maladaptive perfectionismthan for total perfectionism. They were also larger for men thanfor women in total perfectionism and maladaptive perfectionism.Although the confidence intervals for men and women overlappedfor total perfectionism, they did not for maladaptive perfectionism,suggesting a genuine gender difference. This result is similar to thefindings of Park et al. (2010), who reported that maladaptive cop-ing was a greater mediator of the relationship between perfection-ism and psychological distress for men. It is interesting that formen in our sample there was complete mediation: the path be-tween the total perfectionism and depression was no longer signif-

icant in the presence of optimism. For women there was partialmediation.

It is likely that the mediating effect of optimism was strongestfor maladaptive perfectionism because its correlation with opti-mism was stronger than found for total perfectionism. It needs tobe recognized that the total perfectionism score included the mal-adaptive scale items. The research we reviewed did not comparemaladaptive perfectionism to total perfectionism in mediationmodels, but it did compare it to adaptive perfectionism. Flett, Bes-ser, Davis, and Hewitt (2003) found that self-acceptance mediatedthe outcome of socially-prescribed (negative) perfectionism butnot self-prescribed (positive) perfectionism. They also reportedan indirect effect of self-acceptance on other-oriented (negative)perfectionism. Harris et al. (2008) found similar differences be-tween adaptive and maladaptive perfectionism in a mediation con-text: rumination meant more depression for maladaptiveperfectionism, but not for adaptive perfectionism.

Our results indicate a different mediation model for adaptiveperfectionism. Adaptive perfectionism did not show a statisticallysignificant relationship with depression except through optimism,in a suppression model. Adaptive perfectionism predicted increas-ing optimism, which in turn related to lower depression (seeFig. 2). Although optimism showed a stronger mediation effectfor men than women in total and maladaptive perfectionism, theindirect effect of adaptive perfectionism through optimism wasonly found for women; for men the path between adaptive perfec-tionism and optimism was small and statistically insignificant.

Because of the limited number of men, wider confidence inter-vals make it difficult to make inferences. However, the point esti-mates indicate interesting gender differences that merit futureresearch. Hoyle and Kenny (1999) found little effect of sample sizeon the path estimates in a Monte Carlo simulation testing samplesof N = 25–200. Both kappa squared and PM (percent of total effectmediated) are insensitive to sample size (Preacher & Kelley,2011). Interestingly, effect sizes for men are much larger for bothtotal and maladaptive perfectionism, and the correlation betweenoptimism and depression is much stronger for men than for wo-men. Nevertheless, the results are necessarily imprecise due tothe relatively small number of men in our sample.

4.1. Limitations

There is always a question of whether data collected from col-lege students can be generalized to non-academic populations.This study gives some support for generalizability, although theSurvey Monkey respondents were not entirely representative, as78% had at least some college education compared to 55% of adultsin the US population (US Census Bureau, 2010). There were no

430 J. Black, W.M. Reynolds / Personality and Individual Differences 54 (2013) 426–431

significant differences in measure means between the data col-lected through the university research participation pool and thatcollected through Survey Monkey. Mediation analyses results con-ducted separately for these two groups were generally comparablefor both total and maladaptive perfectionism. The university sam-ple showed larger effect sizes and fit a full mediation model. How-ever, the effect size confidence intervals overlapped so we cannotbe positive of a difference in the respective samples. There wasno mediation effect for either group when the model was testedwith adaptive perfectionism. Overall, there were no appreciabledifferences between the two data collection subsamples used inour study.

There are a number of limitations specific to the sample used inthis study. Although the inclusion of data collected online throughSurvey Monkey compensates for some threats to external validity,the sample was still limited. The sample was largely college edu-cated, and predominantly female. In view of the gender differencesfound in the present data, further research with a larger samplethat is more evenly balanced between men and women is needed.Further limitations are imposed by the self-report method, and bythe reliance on the Internet, which restricts participation to thosewith a connection and the inclination to complete a survey. Thecomparability of online versus pencil and paper surveys also arises.However, research suggests that online surveys have minimal dis-advantages when compared to paper and pencil versions of thesame measures (Gosling, Vazire, Srivastava, & John, 2004; Hardre,Crowson, & Xie, 2010).

As with all tests of mediation models based on self-report mea-sures given at the same time, inferences about causation are lim-ited. We have tried to control for reverse effects to some extentby using a ‘‘state’’ measure of depression, while both the MPSand LOT-R are believed to measure general ‘‘trait’’ person charac-teristics. When analyses were conducted with depression as theindependent variable and perfectionism as the dependent variable,there was no evidence of mediation. Nevertheless, causation can-not be ascribed.

In the present study a moderate relationship (r2 = .31) wasfound between optimism and depression. When the two wereinterchanged in the mediation analyses (depression as mediator,optimism as dependent variable), results indicated significant indi-rect effects despite the fact that optimism is typically considered atrait construct and depression a state condition. Although fre-quently used as a measure of optimism, the LOT-R is limited inits level of reliability, thus introducing measurement error, whichis problematic when conducting mediation analyses. Using opti-mism as predictor and perfectionism as mediator also produces amediation model with similar effect sizes. Conceptually, it is plau-sible that optimism causes positive perfectionism, although it isless intuitive to in the case of negative perfectionism. Furtherinvestigation is needed to clarify a coherent causal relationship.

4.2. Recommendations for further research

It is advisable to include more constructs in the model, and touse more than one measure of each (Iacobucci, Saldanha, & Deng,2007). We recommend including a measure of striving and/or max-imization, which has been associated with both optimism and per-fectionism (Fry & Debats, 2009; Hill, Huelsman, & Araujo, 2010;Stoeber et al., 2009). Stress has been shown to mediate correlatesof perfectionism (Chang, 2000, 2006) and could be included in amore complete model.

It is clear that perfectionism is a complex construct. Our resultsindicate that mediational effects of optimism may differ by dimen-sion of perfectionism and by gender. More research is necessary toconfirm and explain this finding. Future research on optimism as a

mediator of perfectionism may also benefit from a more reliableassessment of optimism.

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