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Results

Guy Doron

Analysis was performed using SPSS 12.0. To increase normality, square-root transformations of the Padua-Inventory total and subscales and the BDI total scores were undertaken. Preliminary screening led to the discovery of 5 cases of missing data, in which the participants did not complete all relevant questionnaires. For these cases relevant questionnaire item scores were replaced by the mean item score for that group. Homogeneity of regression was acceptable for all analyses except the relationship between OBQ importance of thoughts subscale and BDI and therefore this ANCOVA was not performed.

ANOVAs with Bonferroni adjustment for multiple comparisons were run on OC symptoms, depression symptoms and total and specific OC-related beliefs, as a function of group (see Table 15). As expected, the OCD group showed the highest level of overall OC symptoms followed by the anxiety control group (AD) and community control group. No group differences were found between the OCD and the AD control group in total OC related cognitions, but both groups showed higher levels of dysfunctional cognitions than the community group. OBQ importance/control of thoughts was the only belief to be uniquely associated with OCD relative to the AD and community group. No group differences were found between the OCD and the AD control group in depression scores.

Table 15. Summary of ANOVA indicating means (SE), and F-statistics for differences between diagnostic groups in OC symptoms, OC related cognitions and depression scores.

Means (Group)
Variable 1.OCD
(n=30)
2.Anx
(n=20)
3.Comm
(n=32)
F statistic Pairwise
comparisons
PI-R 46.50 (3.38) 26.45 (4.14) 12.94 (3.27) 28.00*** 1>2>3
OBQT 194.70 (9.29) 167.05 (11.38) 121.50 (8.99) 15.791*** 1,2>3
OBQOE 74.57 (3.53) 66.35 (4.32) 46.22 (3.42) 17.481*** 1,2>3
OBQPR 74.47 (4.02) 68.05 (4.92) 52.59 (3.89) 8.006*** 1,2>3
OBQIT 45.67 (2.97) 32.65 (3.64) 22.69 (2.88) 15.483*** 1>2>3
BDI 19.20 (1.87) 19.60 (2.29) 5.03 (1.81) 24.899*** 1,2>3

Note: * p<.05; ** p<.01; *** p<.001; OCD=Obsessive compulsive groups; Anx=Anxiety disorder control group; Comm=Community control group; PI-R= Padua Inventory Revised; OBQT = Revised Obsessive Beliefs Questionnaire total score; OBQOE=Threat/resp= overinflated threat/responsibility OBQ subscale; OBQPR =perfectionism /uncertainty OBQ subscale; OBQIT=importance of/need to control thoughts OBQ subscale ; BDI=Beck Depression Inventory total score. F statistics and pairwise comparisons were calculated on the basis of transformed scores.

Attachment representation and OCD

In order to explore the relationship between IWMs of self and IWMs of others, OC symptoms and cognitions within the OCD group, Spearman's Rho correlation analyses were undertaken. Spearman's Rho is a rank order correlation coefficient with a property that has the advantage of attenuating the effect of outliers and skewed distributions, particularly when using small samples. Furthermore, due to the small size of this sample, effect sizes (rather than significant levels) of the correlations were examined.

As expected (see Table 16), small to medium effect size correlations were found between attachment representation and overall OC cognitions (.31< Spearman's p<.48). Somewhat smaller effect size correlations (.21< Spearman's p<.28) were found between attachment representation and total OC symptoms.

Also as predicted, the overall relationship between IWMs of self and specific OC beliefs (.28< Spearman's p<.46) was greater in magnitude than IWMs of others (.18< Spearman's p<.21) and OC beliefs. Of the OC symptoms dimensions, all but checking symptoms showed small to moderate effect sizes with attachment representation. Unexpectedly, the relationship between IWMs of self and others and OC symptoms was of a smaller magnitude than between attachment representation and OC cognitions.

Table 16. Spearman's Rho correlations between attachment dimensions and OCD symptoms
and beliefs in the OCD group (N=30)

Internal working model
of self
Internal working model
of other
PI-R
Total .21 .28
Checking compulsions .04 -.02
Contamination obsessions .29 .35
Obsessional thoughts .26 .24
Obsessional impulses .21 .44
OBQ
Total .49 .31
Overinflated threat / responsibility .46 .21
Perfectionism / uncertainty .53 .22
Importance of / need to control thoughts .28 .18

Note. PI-R= Padua Inventory Revised; PI-R = Padua Inventory-Revised;

To test the hypothesis that the OCD group would show more negative IWMs of self and IWMs of others than both control groups, two ANOVAs with planned simple contrast analyses (with OCD group as the comparison group) were conducted with group membership as the independent variable and IWMs of self and IWMs of other as the dependent variable (See Table 17). The results indicated that the OCD group showed more negative scores on IWMs of self and IWMs of others than the community control group. However, while the OCD group showed more negative IWMs of self then the anxiety control groups, IWMs of others did not show this effect. Furthermore, ANCOVAs indicated that the OCD group showed more negative IWMs of self when controlling for depression and OC-related cognitions.

Table 17. Summary of ANOVA/ANCOVA indicating means (SE), and F-statistics
for differences between diagnostic groups in attachment dimensions.

Means (Group)
Variable Covariate 1.OCD
(n=30)
2.Anx
(n=20)
3.Comm
(n=32)
F Planed
comparisons
IMS   79.83 (3.39) 68.35(4.15) 52.00(3.28) 17.581*** 1>2,3
BDI 76.10(3.37)¹ 63.61(4.14)¹ 58.46(3.63)¹ 6.452** 1>2,3
BDI and OBQ 74.06(3.42)¹² 63.96(4.05)¹² 60.16(3.63)¹² 3.803* 1>2,3
IMO   53.80 (3.63) 60.10(4.45) 38.52(3.52) 8.421*** 1>3
BDI 49.74(3.60)¹ 54.94(4.43)¹ 45.55(3.87)¹ 1.104  
BDI and OBQ 47.15(3.61)¹² 55.39(4.27)¹² 47.70(3.83)¹² 1.345  

Note: * p<.05; ** p<.01; *** p<.001; OCD=Obsessive compulsive groups; Anx=Anxiety disorder control group; Comm=Community control group; PI-R= Padua Inventory Revised; OBQ = Revised Obsessive Beliefs Questionnaire; BDI=Beck Depression Inventory total score; IMS=internal working model of self; IMO=internal working model of other; ¹Means estimated at BDI=4.05 and at ²OBQ=12.41.

Sensitive self and OCD

In order to explore the link between sensitivity in specific self domains and OC symptoms and OC related cognitions within the OCD group, several ANOVAs were conducted. Individuals were classified as sensitive (SEN) or not sensitive (NS) in each domain. ?Sensitive? was operationalized as those who reported on average that the particular domain was important (i.e., greater than the midpoint on the importance items of the subscale), while they were not competent in this domain (less or equal to the midpoint of the competence items of the subscale; see chapter 5 of this thesis). This grouping was performed separately for the three domains of interest within the OCD group resulting in the following classification: Morality (SEN=13; NS=17), Job Competence (SEN=19; NS=11), and Social Acceptability (SEN=16; NS=14).

As hypothesized (see Tables 18 and 19), sensitivity in the domain of morality, but not social acceptability was associated with higher overall OC. Sensitivity in the domain of morality, was also linked with an overall increase in OC related cognitions. Further, the expected relationship between sensitivity in the domain of morality and particular OC symptom dimensions (i.e., all symptom dimensions except impulses of harm) and OC beliefs (i.e., all beliefs except perfectionism/intolerance for uncertainty) was found. Importantly, the effect of sensitivity in the morality domain on overall OC symptoms remained when controlling for depression symptoms .

Contrary to hypothesized, sensitivity in the domains of job competence was not associated with more severe OC symptoms or cognitions. Thus, the only domain within the OCD group where a significant link was found between sensitivity of self and severity of symptoms or cognitions was the morality domain.

Table 18. Summary of ANOVA/ANCOVA indicating means (SE), and F-statistics for differences in OC-symptom dimensions in the OCD group, as a function of whether the individual was sensitive/not sensitive in the three domains.

differences in OC-symptom dimensions

Note: N=30; PI-R= Padua Inventory Revised; OBQ = Revised Obsessive Beliefs Questionnaire; BDI=Beck Depression Inventory total score; NS=Not Sensitive in Domain; SEN=Sensitive in Domain; Mr=morality domain; JC=Job competence self domain; SA=Social acceptance self domain. Means based on square root of subscales.a Means estimated at BDI=4.05.b ANCOVA not performed due to violation of homogeneity of regression.
* p<.05; ** p<.01; *** p<.001;

Table 19. Summary of ANOVA/ANCOVA indicating means (SE), and F-statistics for differences in OC-symptom dimensions in the OCD group, as a function of whether the individual was sensitive/not sensitive in the three domains.

Differences in OC-symptom dimensions

Note: PI-R= Padua Inventory Revised; OBQ = Revised Obsessive Beliefs Questionnaire; BDI=Beck Depression Inventory total score; NS=Not Sensitive in Domain; SEN=Sensitive in Domain; Mr=morality domain; JC=Job competence self domain; SA=Social acceptance self domain. Means based on square root of subscales. a Means estimated at BDI=4.05.b ANCOVA not performed due to violation of homogeneity of regression.
* p<.05; ** p<.01; *** p<.001;

To test our second hypothesis, that the OCD group would show a significantly higher proportion of individuals with sensitivity in the domains of morality and job-competence than individuals in the AD and community control groups, several Χ² analysis of independence were undertaken (see Table 20).

The Χ² analysis of independence indicated there was a relationship between diagnostic status and sensitivity of self in the domain of morality (Pearson's Χ²(2)=15.09, p<.001), and the domain of job competence (Pearson's Χ²(2)=10.94, p<.001), but not in the domain of social acceptability (Pearson's Χ²(2)=2.35, p=ns). Examination of adjusted standardized residuals indicated that the community group was less likely to be sensitive in the morality and job competence domains (adjusted residuals below -2 or above +2 identify cells that depart significantly from the model of independence; see Table 20). In contrast, the OCD group was associated with greater sensitivity in these domains, whereas the AD group showed no association with self sensitivity in these domains.

Table 20. Frequency between diagnostic groups as a function of whether the individual was sensitive/not sensitive in each of the three domains

Diagnostic
Group
Sensitive Domain of self
Morality Job Competence Social Acceptability
NS SEN NS SEN NS SEN
OCD
(n=30)
17
[22.0]
-2.6
13
[8.0]
2.6
11
[17.2]
-2.9
19
[12.8]
2.9
14
[17.2]
-1.5
16
[12.8]
1.5
ANX
(n=20)
12
[14.6]
-1.5
8
[5.4]
1.5
11
[11.5]
-0.2
9
[8.5]
0.2
12
[11.5]
-0.0
8
[8.5]
0.3
COM
(n=32)
31
[23.4]
3.9
1.0
[8.6]
-3.9
25
[18.3]
3.0
7
[13.7]
-3.0
11
[13.7]
1.2
21
[18.3]
-1.2
TOTAL
(n=82)
26.8% 73.2% 42.7% 57.3% 35.0% 47.0%
Χ² (df) 15.09(2)*** 10.94(2)** 2.35(2)

Note: OCD=Obsessive compulsive groups; Anx=Anxiety disorder control group; COM=Community control group; NS=Not Sensitive in Domain; SEN=Sensitive in Domain. ()observed frequency. [] expected frequency.

World assumptions and OCD

Finally, the relationship between world assumptions and OC symptoms and cognitions was examined (see Table 21). As hypothesized, findings indicated small to medium correlations between overall OC symptoms and perceptions of oneself as able to prevent harm in the world (i.e., self controllability) and negative perceptions of self deservingness. Unexpectedly, negative benevolence of the world showed small correlations with overall OC severity, as did the justice assumption. Within the OCD group the belief that people can avoid harm in the world (i.e., controllability belief) showed moderate correlations with overall OC severity.

As expected, controllability based assumptions (i.e., controllability and self controllability) showed small to moderate size correlations with overt symptoms (i.e., checking and contamination symptoms). Also as predicted, covert symptoms showed similar small to moderate size correlations with negative self deservingness. Interestingly, all OC symptoms showed moderate size correlations with negative self deservingness and covert symptoms showed moderate size correlations with the controllability assumptions. Negative perceptions of the world were only linked with contamination symptom severity. Finally, as hypothesized, overall conviction in OC related cognitions showed small to moderate correlations with all world assumptions.

Table 21. Correlations Spearman's Rho between WAS subscales
and OCD symptoms and beliefs in the OCD group (N=30)

Benevolence
of world
Justice Controllability Self
Deservingness
Self
Controllability
PI-R
Total -.18 .11 .40 -.49 .28
Checking compulsions .03 .48 .47 -.45 .19
Contamination obsessions -.27 -.14 .22 -.29 .25
Obsessional thoughts -.19 .14 .52 -.25 .12
Obsessional impulses -.16 -.04 .22 -.49 .06
OBQ
Total -.16 .31 .44 -.60 .23
Overinflated threat / responsibility .18 .36 .55 -.46 .24
Perfectionism / uncertainty -.11 .24 .36 -.58 .28
Importance of / need to control thoughts -.15 .31 .32 -.51 .09

Note: WAS=World Assumption Scale;
PI-R= Padua Inventory Revised;
PI-R = Padua Inventory-Revised;

To test the hypothesis that the OCD group would show more negative self deservingness and benevolence of world assumptions, but stronger beliefs in justice and self-controllability, ANOVAs with planned simple contrast analyses (OCD group being the comparison group) were conducted with group membership as the independent variable and the world assumptions as dependent variables (see table 22). The results indicated that the OCD group showed only one statistically significant difference with the other control groups. That is, individuals suffering from OCD showed lower perceptions of self-deservingness than the community control group. Note, ANCOVAs indicated that the effect of diagnostic group on the self-deservingness assumption remained after controlling for mood scores. Moreover, when controlling for depression symptoms, a significant difference between the OCD group and anxiety controls was revealed. No other group effects were indicated by the ANCOVAs.

Table 22. Summary of ANOVA/ANCOVA indicating means (SE), and F-statistics for differences
between diagnostic groups in world assumptions.

  Means (Group)
WAS
Variable
Covariate 1.OCD
(n=30)
2.Anx
(n=20)
3.Comm
(n=32)
F statistic Planed
comparisons
BW 3.05 (.14) 2.79 (.17) 2.68 (.13) 1.987  
  BDI 3.00 (.14) 2.72 (.18) 2.78 (.16) .958  
  BDI and OBQ 2.99 (.15) 2.72 (.18) 2.78 (.16) .845  
Just 3.93 (.21) 4.14 (.25) 4.22 (.20) .513  
  BDI 4.03 (.22) 4.26 (.27) 4.06 (.23) .263  
  BDI and OBQ 4.20 (.22) 4.23 (.26) 3.91 (.23) .436  
Cont 3.81 (.17) 3.53 (.21) 3.65 (.16) .583  
  BDI 3.94 (.17) 3.69 (.21) 3.42 (.19) 1.797  
  BDI and OBQ 4.10 (.17) 3.66 (.20) 3.29 (.18) 4.635* 1>3
SD 3.61 (.19) 3.10 (.23) 1.96 (.18) 20.166*** 1>3
  BDI 3.30 (.17) 2.70 (.21) 2.50 (.18) 5.237** 1>2,3
  BDI and OBQ 3.14 (.17) 2.73 (.20) 2.63 (.18) b  
SC 2.73 (.15) 2.58 (.19) 2.70 (.15) .213  
  BDI 2.66 (.16) 2.49 (.20) 2.81 (.17) .636  
  BDI and OBQ 2.73 (.17) 2.48 (.20) 2.76 (.18) .660  

Note: WAS=World Assumption Scale; BW= benevolence of World; Just=Justice; Cont=Controllability; Rand=Random; SD=Self Deservingness; SC=Self Controllability; LU=Luck; BW= benevolence of World; BP= Benevolence of People; OBQ = Revised Obsessive Beliefs Questionnaire; BDI=Beck Depression Inventory total score. a Means estimated at BDI=4.05 and at OBQ=12.41. b was not calculated due to violation of homogeneity of variance assumption.
* p<.05; ** p<.01; *** p<.001;

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