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TPB and mental toughness 1
Running head: TPB and mental toughness
Mental Toughness as a Moderator of the Intention-Behaviour Gap in the Rehabilitation
of Knee Pain
1Daniel F. Gucciardi*
1School of Physiotherapy and Exercise Science, Curtin University
Author Notes
*Address correspondence to Daniel Gucciardi, School of Physiotherapy and Exercise
Science, Curtin University, GPO Box U1987, Perth, Australia, 6845. Email:
To appear in: Journal of Science and Medicine in Sport
Accepted for publication: 29th June 2015
TPB and mental toughness 2
Abstract 1
Objectives: The purpose of this study was to investigate the role of mental toughness in 2
maximising the effect of intentions to perform rehabilitative exercises on behaviour among a 3
sample of people with knee pain. 4
Design: Cross-sectional survey, with a 2-week time-lagged assessment of exercise behaviour. 5
Methods: In total, 193 individuals (nfemale = 107, nmale = 84) aged between 18 and 69 years 6
(M = 30.79, SD = 9.39) participated, with 136 (70.5%) retained at both assessment points. At 7
time 1, participants completed an online, multisection survey that encompassed measures of 8
demographic details, severity of problems associated with the knee (e.g., pain, symptoms), 9
past behaviour, mental toughness, and the theory of planned behaviour constructs (TPB; 10
attitudes, subjective norms, perceived behavioural, intentions). Two weeks later, participants 11
retrospectively reported their exercise behaviour for the past 14 days using an online survey. 12
Results: Moderated regression analyses indicated that mental toughness and its interaction 13
with intention accounted for an additional 3% and 4% of the variance in exercise behaviour, 14
respectively. Past behaviour, attitudes, and mental toughness all had direct effects on 15
behaviour, alongside a meaningful interaction between intentions and mental toughness. 16
Specifically, intentions had a stronger effect on exercise behaviour among those individuals 17
high in mental toughness compared to those low in this personal resource. 18
Conclusions: The results of this study shed new light on the intention-behaviour gap by 19
indicating that mental toughness increases the likelihood that intention is translated into 20
action. 21
22
Keywords: intention-behaviour gap; mentally tough; personal resource; physical activity; 23
resource caravan; self-regulation 24
TPB and mental toughness 3
Introduction 25
Exercise – which includes general (e.g., walking) or disease-specific 26
recommendations (e.g., muscle strengthening) regarding planned and structured bodily 27
movements – is often prescribed for the prevention and rehabilitation of health conditions 28
such as knee osteoarthritis1, cancer2, and stroke3. Meta-epidemiological evidence indicates 29
that exercise is just as effective as drug therapy in the secondary prevention of coronary heart 30
disease, treatment of heart failure and prevention of Type 2 diabetes4. Despite these well 31
documented benefits of exercise for health and well-being, adherence to exercise 32
recommendations is often poor and therefore compromises the effectiveness of treatment5. 33
Thus, there is a need to better understand those factors that maximise peoples’ engagement in 34
exercise for rehabilitative and proactive purposes. 35
A diverse range of psychological, behavioural, environmental and social factors are 36
important for the initiation and maintenance of health behaviours6. As theory-based 37
interventions are more effective than atheoretical approaches7, considerable work has been 38
devoted to developing and testing theoretical explanations for health behaviours. Social-39
cognitive theories have received widespread attention as a backdrop upon which to better 40
understand individual-level determinants of behaviour. With regard to exercise, the theory of 41
planned behaviour (TPB8) is one of the most widely adopted frameworks. Within the context 42
of the TPB, one’s intention to engage in the target behaviour is the primary determinant of 43
whether or not one enacts the behaviour. Intention reflects the degree to which one is willing 44
or ready to engage in the behaviour, and the amount of effort they plan to exert towards it. In 45
turn, there are three distal cognitive and affective processes by which individuals form 46
intentions to enact behaviour: attitudes refer to one’s overall evaluation of the experiential 47
(affective) aspects and outcomes (instrumental) of the behaviour; subjective norms reflect 48
one’s perceptions of social pressure from significant others to perform or not carry out the 49
TPB and mental toughness 4
behaviour; and perceived behavioural control captures one’s beliefs regarding the ease or 50
difficulty with which the behaviour can be executed. The usefulness of the TPB for 51
explaining a range of health behaviours including exercise is supported by meta-analytic 52
evidence9. 53
Intentions are clearly important for exercise behaviour10, yet there is a noticeable 54
‘gap’ in that good intentions do not always translate into action11. Accordingly, considerable 55
effort has been directed towards clarifying our understanding of variables that may moderate 56
this association. There is a large body of work that has focused on post-intentional, self-57
regulatory strategies such as action and coping planning as a means by which to translate 58
exercise intentions into behaviour12. Meta-analytic evidence indicates that these self-59
regulatory techniques are effective processes by which to translate physical activity intentions 60
into behaviour13. Despite the benefits of these self-regulatory techniques for bridging the 61
intention-behaviour gap, adherence to these strategies are modest14. An alternative yet 62
complementary approach is to examine personal resources that capture individual differences 63
in peoples’ existing self-regulatory capacity. 64
Learning about individual differences that may foster or forestall purposeful processes 65
designed to regulate thoughts, emotions and behaviours is likely to generate new insights into 66
the intention-behaviour relation. Representing one such personal resource, mental toughness 67
refers to a psychological capacity to attain and sustain one’s self-referenced standards or 68
objectives (e.g., goals, performance) despite varying degrees of situational demands15. Since 69
perseverance is a key behavioural signature of mentally tough individuals16,17, there is reason 70
to believe that this personal resource may foster the translation of intentions into behaviour. 71
For example, research has shown that individuals who self-report high levels of mental 72
toughness are more likely to produce higher levels of work performance, achieve more 73
progress towards academic and social goals over a university semester, and withstand 74
TPB and mental toughness 5
multiple and accumulating stressors over a 6-week period to succeed in their goal to pass a 75
selection test15. Qualitative work indicates that mentally tough individuals identify, evaluate 76
and re-assess goals18, and use long-term goals as a source of motivation19. Mental toughness 77
is therefore one potentially important source of individuality that may underpin the effective 78
regulation of thoughts, emotions and behaviours or the application of self-regulatory 79
strategies in the pursuit of volitional behaviours like exercise rehabilitation. 80
The purpose of this study was to test whether or not mental toughness can bridge the 81
intention-behaviour gap. As mental toughness is a personal resource that fosters behavioural 82
perseverance on a task17 and therefore facilitates positive outcomes for volitional behaviour15, 83
it is expected to moderate the intention-behaviour association such that the strength of the 84
relation will be greatest for people with high levels of mental toughness when compared with 85
low levels of this personal resource. As the TPB is most pertinent when behaviour is 86
volitional (i.e., driven by the will or intent of an individual to perform some action8), the 87
focus in this study is on people with knee pain who have been prescribed rehabilitative 88
exercises by a physiotherapist. Although the home-based rehabilitation exercises have been 89
prescribed by a physiotherapist, it is up to individuals as to whether or not they execute these 90
behaviours according to the professional advice. The TPB has been used extensively to study 91
a wide variety of health behaviours, yet there have been few applications of this theoretical 92
framework in people with knee pain. Thus, this study also provided an opportunity to test the 93
robustness of key theoretical expectations of the TPB. 94
Methods 95
A total of 193 individuals (nfemale = 107, nmale = 84) aged between 18 and 69 years (M 96
= 30.79, SD = 9.39) participated in this study. Of the 193 participants who started the study, 97
136 (70.5%) completed both assessment points. People who met the following criteria were 98
eligible to participate: in the past month, experienced (i) knee pain accompanied by morning 99
TPB and mental toughness 6
stiffness lasting less than 30 minutes, (ii) crepitus on active movements, (iii) tenderness of the 100
bony margins of the knee joint, and (iv) had consulted a physiotherapist about their knee pain 101
and therefore had been provided with information regarding specific rehabilitative exercises. 102
Participants were excluded if they had ever experienced a cardiac event (e.g., heart attack), 103
had major bone or joint surgery (e.g., ACL), or a BMI greater than 3520. 104
Demographic data were collected by self-report and included age, gender, height, and 105
weight. The subscales of pain, symptoms and function in activities in daily living from the 106
Knee Injury and Osteoarthritis Outcome Score21 provided an assessment of the severity of 107
problems associated with the knee. Mental toughness was assessed using an established 8-108
item inventory15. Items designed to capture the theory of planned behaviour variables were 109
developed in accordance with Azjen’s22 guidelines (see Appendix A of the Supplementary 110
Material). TPB instruments that have been developed in accordance with these guidelines 111
have demonstrated excellent reliability and validity in previous research23,24. Consistent with 112
the approach used in previous research25, exercise behaviour was assessed using a self-report 113
measure in which participants indicated the frequency of rehabilitative exercises performed 114
on average for 30 minutes over the past two weeks. In this study, rehabilitative exercises 115
were defined as those activities that are intended to reduce the amount of pain experienced 116
and/or strengthen those muscles that support the knee and surrounding areas with the view of 117
preventing future knee pain. 118
All study procedures were approved by [name blinded for peer-review] human 119
research ethics committee. Participants were recruited and completed the study anonymously 120
online via SocialSci (www.socialsci.com). Potential participants were recruited to this 121
platform via online advertising, print media, and live recruitment where they signed up to 122
take part in academic research in return for small points-based Amazon credits. The first 123
section of the survey contained measures to ascertain an individual’s eligibility for the study. 124
TPB and mental toughness 7
Eligible and consenting participants subsequently provided demographic details and 125
completed measures of the TPB, severity of problems associated with knee pain, mental 126
toughness, and their intended exercise behaviour over the preceding 14 days. Two weeks 127
later participants provided a self-report of their exercise behaviour over the preceding 14 128
days. 129
Data was initially screened for violations of assumptions of normality and outliers. 130
First, to examine the possibility of an attrition bias, an analysis of variance (ANOVA) was 131
performed to test for differences in the study variables at time 1 between those participants 132
who completed the time 2 survey and those who did not respond, whereas a chi-square (χ2) 133
analysis was performed for gender (see Table 1). Second, a hierarchical multiple regression 134
was performed to assess the effects of the distal predictors of intentions. Covariates were 135
entered at Step 1 (demographic factors, severity of knee problems, and past behaviour), with 136
attitudes, subjective norms and perceived behavioural control added at Step 2. Third, a 137
moderated hierarchical multiple regression was performed to assess the importance of social-138
cognitive factors and mental toughness as determinants of exercise behaviour, while 139
controlling for covariates. All independent variables were standardised prior to the regression 140
analyses; gender was dummy coded (0 = female, 1 = male). Covariates were entered at Step 141
1; the TPB variables were entered at Step 2; mental toughness was entered at Step 3; and the 142
interaction between mental toughness and intentions was entered at Step 4. This approach 143
permitted an examination of the incremental validity of mental toughness, and its interaction. 144
Simple slopes analyses of the interaction effect were plotted and tested at one standard 145
deviation above and below the mean, and at the mean of mental toughness26. 146
Results 147
Data screening revealed no violations against assumptions of multivariate outliers 148
(i.e., using a p <.001 criterion for Mahalanobis D2), skewness (all variables < + 1.3), and 149
TPB and mental toughness 8
kurtosis (all variables < + 3.6) for subscales of all study variables. However, seven univariate 150
outliers were identified with regard to the psycho-social variables (i.e., z score > + 3.29). As 151
the exclusion of these outliers did not alter the results of the main analyses, they were 152
retained for all analyses and the reported findings. Bivariate correlations among study 153
variables and internal reliability estimates of self-reported severity of knee problems, mental 154
toughness and the TPB are provided in Appendix B of the Supplementary Material. All 155
measures demonstrated adequate levels of internal reliability. An overview of the ANOVA 156
summary statistics is detailed in Table 1. Participants who responded at both time points did 157
not differ from those individuals who dropped out of the study. With regard to gender, 158
females (n = 39; 36.4%) were more likely than males (n = 18; 21.4%) to drop out of the 159
study, χ = 5.95, p = .051. 160
The control variables accounted for 12% of the variance in intention, F (7, 128) = 161
2.56, p = .017, η2 = .129, 90% CI = .012, .171 (see Steiger27 for an explanation of the use of 162
90% confidence intervals for eta squared). Only past behaviour was a meaningful 163
determinant of intention (B = .31, 95% CI = .13, .49, p = .001). The inclusion of the TPB 164
distal predictors of intentions accounted for an additional 27% of the variance, F (3, 125) = 165
18.56, p < .001, η2 = .308, 90% CI = .188, .393. Past behaviour (B = .24, 95% CI = .09, .39, p 166
= .002), attitudes (B = .30, 95% CI = .15, .46, p < .001) and perceived behavioural control (B 167
= .30, 95% CI = .14, .45, p < .001), but not subjective norms (B = .10, 95% CI = -.06, .27, p = 168
.223), were important determinants of intention. 169
With regard to the prediction of exercise behaviour, at Step 1 of the moderated 170
regression, the control variables accounted for 15% of the variance in exercise behaviour, F 171
(7, 128) = 3.16, p = .004, η2 = .147, 90% CI = .029, .201. There was a significant effect for 172
past behaviour (B = 1.30, 95% CI = .67, 1.93, p < .001). The inclusion of the TPB variables 173
to the model at Step 2 accounted for an additional 11% of the variance in exercise behaviour, 174
TPB and mental toughness 9
F (4, 124) = 4.48, p = .002, η2 = .126, 90% CI = .030, .197. There were significant effects for 175
past behaviour (B = .90, 95% CI = .27, 1.54, p = .006) and intentions (B = .86, 95% CI = .17, 176
1.60, p = .015). The inclusion of mental toughness at Step 3 indicated that the main effect (B 177
= .72, 95% CI = .11, 1.33, p = .022) accounted for an additional 3% of the variance in 178
exercise behaviour, F (1, 123) = 5.41, p = .022, η2 = .042, 90% CI = .003, .113. At Step 4, the 179
inclusion of the interaction between mental toughness and intentions accounted for an 180
additional 4% of the variance in exercise behaviour, F (1, 122) = 6.30, p = .013, η2 = .049, 181
90% CI = .006, .123. There were significant effects for past behaviour, attitudes, mental 182
toughness and the interaction between intentions and mental toughness (see Table 2). Simple 183
slopes analyses indicated that the association between intentions and exercise behaviour was 184
its greatest when mental toughness was high (B = 1.172, t = 3.67, p < .001), with a less 185
amplified positive relation at moderate mental toughness (B = .50, t = 1.379, p = .17) and a 186
slightly inverse association at low levels of mental toughness (B = -.17, t = -.40, p = .69). A 187
visual display of the simple slopes is depicted in Figure 1. 188
Discussion 189
The purpose of this study was to investigate the role of mental toughness in 190
maximising the effect of intentions to perform rehabilitative exercises on behaviour among a 191
sample of people with knee pain. Overall, the findings of this study provided additional 192
support for key theoretical expectations of the TPB in a sample of people with knee pain. In 193
terms of unique contributions, the results of this study shed new light on the intention-194
behaviour gap by indicating that mental toughness increases the likelihood that intention is 195
translated into action. 196
Meta-analytic reviews of prospective correlational tests of the TPB have shown that 197
the TPB explains small and moderate amounts of variance in behaviours and intentions, 198
respectively9,10. As one of the first tests of the TPB in people with knee pain, the results of the 199
TPB and mental toughness 10
current study provided additional support for several of these theoretical expectations. First, 200
the TPB constructs explained over twice as much of the variance in intentions when 201
compared with behaviour. Second, attitude and perceived behavioural control evidenced the 202
greatest association with intentions. Third, although not amenable to change, past behaviour 203
is a primary determinant of future behaviour. Despite these positive results, several of the 204
current findings were incongruent with existing meta-analytic data9,10 and theoretical 205
expectations8. For example, the effect of intention on behaviour was attenuated by the 206
inclusion of mental toughness and its interaction with intention. Moreover, perceived 207
behavioural control was not directly related to exercise behaviour, even when mental 208
toughness was excluded from the analysis. Collectively, these results strengthen claims that 209
the efficacy of the TPB depends on the target behaviour9, and reinforce the importance of 210
formative research as a precursor to effective TPB-based interventions. 211
This study makes an important contribution to the literature by demonstrating the 212
importance of mental toughness as a determinant of exercise behaviour. Both direct and 213
moderating effects of mental toughness on exercise behaviour were examined and found to 214
be meaningful. In terms of the moderation hypothesis, intentions had a stronger effect on 215
exercise behaviour among those individuals high in mental toughness compared to those low 216
in this personal resource. This study is the first to report such an interaction effect. As these 217
effects were evidenced while accounting for control variables and the TPB constructs, these 218
findings provide further evidence for the incremental validity of mental toughness over and 219
above well-established predictors of volitional behaviours. From a practical standpoint, it is 220
encouraging that individuals with high levels of mental toughness and intentions reported 221
engaging in over three sessions of 30 mins per week, which is consistent with exercise 222
recommendations for people with knee osteoarthritis28. 223
TPB and mental toughness 11
At least two possible explanations might account for the direct and moderation effects 224
of mental toughness observed in this study. First, given that perseverance is a behavioural 225
signature of mental toughness16,17, it is likely that individuals with high levels of mental 226
toughness persist longer in duration when working towards their exercise goals. Second, as a 227
resource caravan that is central to coping processes (e.g., affective self-regulatory 228
capabilities, ability to bounce back from setbacks)15, mental toughness may prove beneficial 229
in ensuring that people are able to carry out their intentions despite the presence of stressors, 230
especially when perceived behavioural control for the target behaviour is low. Nevertheless, 231
the inclusion of mental toughness as an additional predictor within the context of the TPB is 232
at odds with the principle of compatibility; that is, a new variable should be behaviour-233
specific and therefore measured at the same level of specificity as the target behaviour or 234
action29. It is therefore important that these findings are replicated in future research before 235
any definitive conclusions can be made in this regard. 236
Conclusion 237
This study is the first to test the moderating role of mental toughness on the intention-238
exercise behaviour relation. Missing from this study is an understanding of how mental 239
toughness enables people to engage in exercise rehabilitation. For example, do individuals 240
simply try harder and persevere? Are people less affected by stressors? There are other 241
limitations to the current study that open up important avenues for future research. First, all 242
study variables were measured via self-report and therefore may be influenced by common 243
method bias. Second, despite the temporal lag in the assessment of exercise behaviour over a 244
2-week period, the design is not longitudinal nor experimental in nature and therefore cannot 245
provide evidence for causality. Third, the large age range of participants in this study is both 246
a strength (e.g., ability to generalise) and weakness, as the TPB is most predictive amongst 247
young people9. Finally, it is difficult to control for motivational strategies offered by 248
TPB and mental toughness 12
physiotherapists and their influence on patients in an observational, cross-sectional study that 249
did not incorporate measures of these variables. Despite these limitations, this study offers a 250
new insight into a personal resource that may help translate good intentions into exercise 251
behaviour. 252
Practical Implications 253
• Mental toughness is an important personal resource that can enable people to make the most 254
out of good intentions 255
• Enhancing peoples’ perceptions of control over a specific behaviour can enhance the 256
likelihood that they will form strong intentions to engage in the behaviour 257
• For people with low intentions, emphasise the experiential or affective aspects (e.g., 258
enjoyable) and instrumental outcomes (e.g., individualised benefits) of engaging in exercises 259
for their knee pain 260
TPB and mental toughness 13
Acknowledgements
Gucciardi is supported by a Curtin Research Fellowship.
TPB and mental toughness 14
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TPB and mental toughness 17
Table 1. Overview of ANOVA summary statistics for attrition bias analyses (Note: normalised scores for symptoms, pain, and daily function).
Non-Responders (n=57) Responders (n=136) ANOVA (df = 1, 191)
M SD 95% CI M SD 95% CI F p η2 [90% CI]
Age 30.73 8.42 28.50, 32.97 30.81 9.80 29.15, 32.47 .003 .957 .000 [.000, .001]
BMI 24.46 5.01 23.13, 25.80 24.59 4.37 23.85, 2533 .032 .858 .000 [.000, .007]
Symptoms 71.42 16.94 66.93, 75.92 69.11 15.82 67.50, 72.09 .822 .366 .004 [.000, .033]
Pain 76.51 17.63 71.83, 81.19 75.93 15.54 73.30, 78.57 .050 .823 .000 [.000, .011]
Daily function 85.84 17.48 81.20, 90.48 81.10 18.06 78.03, 84.17 2.824 .095 .015 [.000, .054]
Attitudes 4.89 1.18 4.58, 5.20 4.98 1.18 4.78, 5.18 .245 .621 .001 [.000, .022]
Subjective norms 4.05 1.56 3.63, 4.46 3.95 1.45 3.70, 4.19 .183 .669 .001 [.000, .020]
Behavioural control 4.90 1.32 4.55, 5.25 4.54 1.39 4.31, 4.78 2.701 .102 .014 [.000, .053]
Intentions 3.20 1.67 2.75, 3.64 3.10 1.61 2.83, 3.37 .137 .712 .001 [.000, .019]
Mental toughness 5.12 1.14 4.82, 5.43 4.96 1.02 4.79, 5.14 .891 .346 .005 [.000, .034]
Exercise behaviour 1.12 2.84 .36, 1.87 .90 2.19 .53, 1.27 .331 .565 .002 [.000, .024]
TPB and mental toughness 18
Table 2. Moderated regression (Step 4) predicting exercise behaviour from TPB variables,
mental toughness, and interaction term while accounting for demographic covariates.
Unstandardised Coefficient
B 95% CI
(low, high)
SE β t p
Gender -.72 -1.84 .39 .56 -.10 -1.28 .202
Age -.18 -.74 .39 .29 -.05 -.62 .538
BMI .22 -.32 .77 .28 .06 .80 .426
Past behaviour 1.04* .43 1.66 .31 .29* 3.35 .001
Symptoms -.29 -.98 .39 .34 -.08 -.86 .394
Pain .12 -1.11 1.36 .62 .03 .20 .844
Function .11 -1.09 1.32 .61 .03 .18 .855
Intentions .50 -.22 1.22 .36 .14 1.38 .170
Attitudes .72* .07 1.36 .33 .20* 2.19 .030
Subjective norms -.09 -.72 .53 .32 -.03 -.30 .767
PBC -.44 -1.09 .21 .33 -.12 -1.34 .184
Mental toughness .82* .21 1.42 .30 .23* 2.67 .008
MTxINT .67* .14 1.20 .27 .21* 2.51 .013
Note: BMI = body mass index; PBC = perceived behavioural control; MTxINT = interaction
between mental toughness and intentions; gender (0 = female, 1 = male).
TPB and mental toughness 19
Figure 1. Visual display of simple slopes of the interaction between mental toughness and
intentions for exercise behaviour.
TPB and mental toughness 20
Supplementary Material
Appendix A – Items of the theory of planned behaviour
Items measuring attitude were preceded by the common stem, “For me, doing rehabilitative
exercise, on average, for 30 minutes about 3 times a week over the next 2 weeks would be…”
Participants’ responses are made on four 7-point semantic differential scales with the following bi-
polar adjectives: “pleasant-unpleasant”, “enjoyable-unenjoyable”, “beneficial-harmful” and “wise-
foolish”. Measures of subjective norms (two items; e.g., “People who are important to me think I
should do rehabilitative exercises for my knee, on average, for 30 minutes about 3 times a week
over the next 2 weeks”), perceived behavioural control (two items; e.g., “How much control do you
feel you have over completing rehabilitative exercises for your knee, on average, for 30 minutes
about 3 times a week over the next 2 weeks”) and intention (two items; e.g., “I intend to spend, on
average, 30 minutes doing rehabilitative exercises for my knee about 3 times a week over the next 2
weeks) were rated on 7-point Likert-type scales (e.g., 1 = strongly disagree, 7 = strongly agree).
TPB and mental toughness 20
Appendix B – Descriptive statistics and bivariate correlations among study variables for the total sample (n = 136).
1 2 3 4 5 6 7 8 9 10
1 Exercise (t1) -
2 Exercise (t2) .35** -
3 Attitudes .18* .34** (.82)
4 Subjective Norms .17 .14 .28** (.79)
5 Perceived Behavioural Control .00 .13 .34** .22** (.84)
6 Intentions .32** .40** .48** .30** .41** (.96)
7 Mental Toughness -.02 .21* .02 .09 .36** .28** (.91)
8 Symptoms -.14 -.13 -.14 -.21* .01 -.13 -.03 (.67)
9 Pain -.33** -.14 -.03 -.32** .04 -.17 -.07 .59** (.87)
10 Function -.30** -.12 -.04 -.34** .09 -.17 -.06 .58** .89** (.96)
Mean .90 1.86 4.98 3.95 4.54 3.10 4.96 50.16 75.93 81.10
Standard deviation 2.19 3.61 1.18 1.45 1.39 1.61 1.02 11.59 15.54 18.07
Range 0-16 0-28 1-7 1-7 1-7 1-7 1-7 10.71-85.71 22.22-100 25-100
Note: internal reliability estimates are presented on the diagonal in parentheses; * p < .05; ** p < .001.