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A prospective examination of the association between the centrality of a loss and post-loss psychopathology
Journal of Affective Disorders 137 (2012) 117–124
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Research report
A prospective examination of the association between the centrality of a loss and post-loss psychopathology Paul A. Boelen ⁎ Clinical and Health Psychology, Utrecht University, PO Box 80140, 3508 TC Utrecht, The Netherlands
a r t i c l e
i n f o
Article history: Received 26 October 2011 Received in revised form 2 December 2011 Accepted 3 December 2011 Available online 10 January 2012 Keywords: Bereavement Prolonged Grief Disorder Centrality Identity Memory
a b s t r a c t Background: Research has shown that the extent to which a negative event has become central to one's everyday inferences, life-story, and identity is associated with the severity of psychopathology experienced following this event. The current study aimed to extend this prior research by examining the prospective linkage between the centrality of a loss-event and post-loss psychopathology. Methods: To this end, 176 individuals, bereaved within the past year, completed the Centrality of Event Scale (CES) with their loss as the anchor event, together with measures of Prolonged Grief Disorder (PGD), depression, and bereavement-related Posttraumatic Stress-Disorder (PTSD) and complementary questionnaires. One hundred participants again completed symptom-measures one year later. Results: Findings showed that (a) the centrality of a loss was associated with concurrent symptom-levels of PGD, depression, and PTSD; (b) the centrality of a loss predicted PGDseverity, depression-severity, and PTSD-severity one year later, after controlling for baseline symptom-levels; (c) these cross-sectional and prospective linkages remained significant when controlling for relevant demographic and loss-related variables, as well as for indices of neuroticism, attachment anxiety, attachment avoidance and persistent closeness to the lost person. Limitations: Limitations include the under-representation of men and the reliance on selfreport measures. Conclusions: The current findings provide evidence that the centrality of a negative event is a prospective predictor of post-event psychopathology. © 2011 Elsevier B.V. All rights reserved.
1. Introduction For a minority of people, the death of a loved one precipitates the development of Prolonged Grief Disorder (PGD; Prigerson et al., 2009). PGD is a clinical condition that encompasses specific grief-reactions (including separation distress, difficulties accepting the loss and moving on without the lost person) that cause significant distress and disability at least six months after the death. Symptoms of PGD are distinct from depression and bereavement-related
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Posttraumatic Stress-Disorder (PTSD) and, if left untreated, associated with significant impairments in health and quality of life (Prigerson et al., 2009). There is growing evidence that cognitive-behavioural therapy is efficacious in the treatment of PGD and related symptoms (Boelen et al., 2007). Nevertheless, not all patients with PGD profit from this treatment (cf., Wittouck et al., 2011). It is therefore important to continue searching for mechanisms involved in the development and maintenance of PGD in order to inform refinement of PGD-treatment interventions. In literature on PTSD, there is growing interest in the concept “centrality of event” put forth by Berntsen and Rubin (2006, 2007). This concept refers to the degree to which the
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memory of a negative life-event forms a reference point for the attribution of meaning to other events, a turning point in a person's life-story, and a core component of a person's identity. It has been argued that greater event-centrality is associated with more intense post-event psychopathology, because it heightens the accessibility of memories of the event and colours the manner in which new experiences – some of which could correct erroneous conclusions about the self and future drawn on the basis of the event – are perceived and processed. Berntsen and Rubin (2006) constructed the Centrality of Event Scale (CES) to measure the centrality of event concept and found the scale to have adequate psychometric properties. A growing number of studies using the CES have found support for an association between event-centrality and post-event psychopathology. Berntsen and Rubin (2007) investigated event-centrality among college-students exposed to different kinds of negative life-events and found event-centrality to be positively associated with symptoms of PTSD, depression, and dissociation. This finding has been replicated in other student samples (Boals, 2010; Boals and Schuettler, 2011) and combat veteran samples (Brown et al., 2010). In addition, a recent study showed that the degree to which bereaved individuals experienced their loss as central was significantly associated with symptomlevels of PGD and related symptoms, even when controlling for other relevant cognitive-behavioural and personality-related variables (Boelen, 2009). A limitation of studies conducted so far is that they all relied on cross-sectional designs. Hence, research has yet to show that event-centrality is an actual predictor of event-related psychopathology and not just an epiphenomenon of such psychopathology. The current study aimed to expand prior research by examining the prospective linkage of event-centrality and post-event psychopathology, among people confronted with the death of a loved one. Specifically, individuals, all bereaved within the past year, were administered the CES and measures tapping symptoms of PGD, depression, and bereavement-related PTSD, together with complementary questionnaires (Time 1). They were invited to complete symptom-measures again one year later (Time 2). This study had two central aims. The first aim was to replicate prior findings of a cross-sectional linkage between the centrality of a loss-event and symptom-levels of PGD, depression, and PTSD, among relatively recently bereaved individuals. The second central aim was to examine the prospective linkage between the centrality of a loss and post-loss psychopathology one year later, controlling for baseline symptom-levels. Based on prior theorising (Berntsen and Rubin, 2006, 2007) we expected significant concurrent and prospective linkages to emerge. Secondary to these two central aims, we also examined the extent to which associations between event-centrality and post-loss psychopathology remained significant when controlling for background and loss-related variables that have often been found to influence grief-severity (e.g., mode of death, kinship to the deceased). Based on prior research (Boelen, 2009) event-centrality was expected to be associated with post-loss psychopathology, even when controlling for these variables.
Finally, we investigated whether or not event-centrality predicted post-loss psychopathology above and beyond personality factors of neuroticism, attachment anxiety, and attachment avoidance, and the currently experienced degree of closeness to the lost person. These variables were included because they have all been found to affect bereavementoutcome (e.g., Boelen and Klugkist, 2011; Bonanno et al., 2002; Wijngaards-de Meij et al., 2007). More specifically, neuroticism was investigated because it was deemed relevant to examine if event-centrality predicted symptomlevels beyond this general predisposition toward negative thinking and feeling (Watson and Clark, 1984). Attachment anxiety, attachment avoidance, and persistent closeness to the lost person were included to rule out that associations between the centrality of a loss and post-loss-psychopathology were accounted for by the person's generalised predisposition toward an insecure attachment style and the continuation of a sense of closeness to the lost person. Based on the notion that the CES taps into a unique phenomenon, representing the degree to which the loss has become a core part of identity, and is not just a corollary of more generic personality features and continued closeness to the lost person, we expected event-centrality to be associated with post-loss psychopathology, even when controlling for neuroticism, attachment anxiety, attachment avoidance, and persistent closeness. 2. Method 2.1. Participants and procedure Participants were recruited through announcements on Dutch Internet-sites with information about grief and bereavement in the period 2009–2010. These announcements solicited bereaved people to participate in a research programme on grief by completing questionnaires. People interested in participating were directed to a secured questionnaire on the internet or, if so wished, were sent a paper-version of the questionnaire. At Time 1, 622 questionnaires were sent out, 468 of which (75.2%) were returned. In total, 176 participants who were confronted with a loss within the preceding year were invited to complete symptommeasures of PGD, depression, and PTSD (but none of the other questionnaire measures administered at Time 1) again, approximately one year later (Time 2). One hundred participants (56.8%) did so. Because we were particularly interested in the impact of loss-centrality as experienced in the early phases of bereavement on subsequent grief, we only invited participants who were still in their first year of bereavement to compete questionnaires a second time, one year later. Those who continued to participate at Time 2 (N = 100) did not differ from those who did not (N = 76) on any of the variables that were assessed at Time 1. Data of the 176 mourners with data at Time 1 were included in the cross-sectional analyses. Data of the 100 mourners with data at Time 1 and Time 2 were included in the prospective analyses. At Time 1, N = 143 (81.2%) participants completed the questionnaires online and N = 33 (18.8%) completed a paper-version. Table 1 summarises background characteristics of the participants. Most participants were women bereaved by the loss of a partner.
P.A. Boelen / Journal of Affective Disorders 137 (2012) 117–124 Table 1 Demographic and loss-related characteristics and symptom-severity of the sample.
Demographic characteristics Gender (N (%)) Men Women Age (years) (M (SD)) Highest education (N (%)) Primary/secondary school College/university
Cross-sectional sample
Prospective sample
(N = 176)
(N = 100)
22 (12.5) 154 (87.5) 45 (12.2)
10 (10) 90 (90) 45.8 (12.1)
97 (55.1) 79 (44.9)
54 (54) 46 (46)
Loss characteristics Deceased is (N (%)) Partner 91 (51.7) Child 16 (9.1) Other relative 69 (39.2) Cause of death is (N (%)) Illness 87 (49.4) Violent (accident, suicide, homicide) 20 (11.4) Unexpected medical cause 51 (29) (e.g., heart attack) Other cause 18 (10.2) Time from loss in months (M (SD)) 4.8 (3.6) I was present at time of the death (N (%)) No 85 (48.3) Yes 89 (50.6) Unexpectedness of the death 3.1 (1.6) a (M (SD)) Symptom-scores Prolonged Grief Severity T1 (M (SD)) Prolonged Grief Severity T2 (M (SD)) Depression-severity T1 (M (SD)) Depression-severity T2 (M (SD)) PTSD-severity T1 (M (SD)) PTSD-severity T2 (M (SD))
32 (8.9) – 8.5 (5.5) – 18.6 (8.9) –
55 (55) 10 (10) 35 (35) 48 (48) 9 (9) 32 (32) 11 (11) 4.8 (3.5) 50 (50) 48 (48) 3.1 (1.6)
32.1 (8.8) 27.4 (9.1) 8.8 (5.4) 6.0 (4.7) 18.8 (8.4) 14.0 (8.6)
Note. Some numbers do not add up to N = 176 or N = 100 due to occasional missing values. PTSD = Posttraumatic Stress Disorder. a Unexpectedness was rated on a 1 = expected to 5 = totally unexpected scale.
2.2. Measures 2.2.1. PGD-scale The PGD-scale is a short version of the Inventory of Complicated Grief-revised (ICG-r), a 30 items measure of PGDsymptoms. The English (Prigerson et al., 2009) and Dutch (Boelen et al., 2003) versions of the ICG-r have adequate psychometric properties. The PGD-scale contains 11 slightly modified items from the ICG-r that resemble recently proposed criteria for PGD, including items tapping separation distress, difficulties accepting the loss, and bitterness/anger about the loss. Participants rate the occurrence of symptoms in the preceding month on 5-point scales with anchors 1 = never to 5 = always. Items are summed to form an overall PGD-severity score. The internal consistency of the scale at Time 1 was α= .89 (N= 176) and at Time 2 was α=.91 (N =100). 2.2.2. Depression subscale of the hospital anxiety and depression scale (HADS-D) The 7-item depression subscale of the HADS (Zigmond and Snaith, 1983) was used to assess depression-severity.
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Respondents rate the presence of seven depression symptoms during the previous week, on 4-point scales. The English (Zigmond and Snaith, 1983) and Dutch versions (Spinhoven et al., 1997) have yielded adequate psychometric properties. The internal consistency of the scale at Time 1 was α = .92 (N = 176) and at Time 2 was α = .91 (N = 100). 2.2.3. PTSD symptom scale self-report version (PSS-SR) The PSS-SR is a 17-item measure of PTSD. Respondents rate the frequency of symptoms on 4-point scales with anchors 0 = not at all to 3 = five or more times per week/almost always. The index event was defined as “the death of your loved one”. The English (Foa et al., 1993) and Dutch versions (Engelhard et al., 2007) have good psychometric properties. The internal consistency of the scale at Time 1 was α = .86 (N = 176) and at Time 2 was α = .89 (N = 100). 2.2.4. Relationship questionnaire (RQ) The RQ is a measure of attachment as applying to close (not necessarily romantic) relationships in general (Griffin and Bartholomew, 1994). It contains four descriptions of attachment prototypes (secure, fearful, preoccupied, and dismissing). Participants rate descriptions on 7-point scales ranging from 1 = not at all like me to 7 = very much like me. Ratings are used to obtain scores on the dimensions of attachment anxiety and attachment avoidance. The attachment anxiety score was obtained by subtracting the secure and dismissing scores from the summed fearful and preoccupied scores. The attachment avoidance score was derived by subtracting the secure and preoccupied scores from the summed fearful and dismissing scores. The RQ has adequate psychometric properties (Griffin and Bartholomew, 1994). 2.2.5. Inclusion of other in self (IOS) scale This is a single-item, pictorial measure that taps a subjective sense of interconnectedness between self and other (Aron et al., 1992). It consists of seven pairs of circles, one that includes the word self and one that includes the word other, that overlap to an increasing degree. Respondents have to select the pair that best describes their relationship with a particular person. In the current study, participants were asked to select the pair that best described their relationship with the lost person, at this moment in time. The IOS Scale has demonstrated adequate reliability and validity (e.g., strong correlations with other measures of relationship closeness) in several studies (Aron et al., 1992). 2.2.6. Centrality of event scale (CES) The CES – developed by Berntsen and Rubin (2006) – is a 7-item questionnaire, that measures the extent to which a negative life-event is central to one's everyday inferences (“This event has become a reference point for the way I understand myself and the world”), life-story (“This event permanently changed my life”), and identity (“I feel that this event has become part of my identity”). Items are rated on 5-point scales (1 = totally disagree to 5 = totally agree). In the present study, the loss of a loved one was the designated negative life-event. The CES has adequate psychometric properties (e.g., Berntsen and Rubin, 2006; Boelen, 2009). In the current study, the internal consistency was α = .84.
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2.2.7. Ten-item personality inventory (TIPI) neuroticism scale We used the 2-item neuroticism scale of the TIPI (Gosling et al., 2003) to measure neuroticism. Its two items are “I see myself as calm, emotionally stable” and “I see myself as anxious, easily upset” which are rated on 7-point scales (1 = disagree strongly, to 7 = agree strongly). The neuroticism score was the mean of the two items, after reversing scores of the former item (α = .79). The TIPI has been found to have adequate psychometric properties, including large convergence with longer measures of neuroticism (Gosling et al., 2003). 3. Results 3.1. Descriptive statistics Mean scores on the symptom-measures at Time 1 and Time 2 are shown in Table 1. Paired sample t-tests showed that symptom-levels of PGD (t(99) = 6.29), depression (t(99) = 5.89), and PTSD (t(99) = 6.40) declined significantly from Time 1 to Time 2 (ps b .001). Following guidelines provided by Prigerson et al. (2009), 32 participants (18.2%) met criteria for “caseness” of PGD. Compared with Dutch reference groups examined by Spinhoven et al. (1997), scores on the HADS-D did not differ significantly from scores of psychiatric outpatients (M=8.4 vs. M=9.3, t(175)=−1.96, p=.051). Scores on the PSS were lower than scores of 65 patients diagnosed with PTSD using a clinical interview in a study conducted by Engelhard et al. (2007). Altogether, the current sample was best described as a subclinical sample. 3.2. Variation in symptom-severity and CES scores as a function of demographic and loss-related variables We examined the degree to which scores on the symptommeasures at Time 1 (N = 176) and Time 2 (N = 100) varied as a function of demographic and loss-related variables (i.e., gender, age, education, relationship with deceased, cause of death, time since loss, being present at time of death [yes/no], and perceived unexpectedness of the death [rated on a 1 = expected to 5 = totally unexpected scale]). The participant's age was significantly correlated with depression at Time 2; r(98) = .21, p b .04. Time since loss was associated with PTSD-severity at Time 1; r(174) = −.16, p = .03. Educational level was associated with symptom-levels of PGD and PTSD at both time points; participants who went to primary/secondary school had higher scores than those who went to college or university (all Fs > 5.60, all ps b .02). Relationship with the deceased affected all symptom-scores at Time 1 and Time 2 (all Fs > 3.48, all ps b .04). Pair-wise comparisons showed that participants who had suffered the loss of a partner or child consistently had higher symptomscores compared to participants who had suffered the loss of some other loved one (ps b .05). Finally, perceived unexpectedness of the death was significantly related with Time 1 PGD-severity (r(173) = .29), and also with PGD-severity (r(98) = .26), depression-severity (r(98) = .30), and PTSDseverity (r(98) = .24) at Time 2 (ps b .02). CES-scores varied as a function of kinship (F(2, 172) = 17.90, p b .001); those confronted with the loss of a parent or child experienced the loss as more central compared to those who lost some other loved one. There was also an effect of
cause of death (F(3, 171) = 3.62, p b .02) which was due to mourners confronted with violent loss having higher CESscores than those confronted with losses due to another cause (i.e., other than illness, a violent cause, or an unexpected medical cause). Furthermore, CES-scores were positively correlated with time since loss (r(174) = .22) and unexpectedness of the loss (r(174) = .21, ps b .01) 3.3. Regression analyses predicting symptom-scores at time 1 To examine the concurrent associations of centrality of the loss (CES) with symptom-scores, three hierarchical regression analyses were conducted predicting PGD, depression, and PTSD-scores at Time 1, respectively. In each analysis, independent variables were entered in four blocks representing (i) relevant demographic and loss-related variables (i.e. those associated with Time 1 symptom-scores); (ii) personality indices (neuroticism, attachment anxiety, attachment avoidance); (iii) interpersonal closeness (IOS-scale); and (iv) CES-scores. Table 2 shows the percentages of variance explained by each block when entered as a first block to the equation, and the percentages of variance explained by each block when entered as a last block (i.e., the percentages of variance explained by each block, when controlling for the variance explained by the other three blocks). Table 2 also shows regression coefficients from the final model. The model predicting PGD-scores was significant; F(8, 148) = 23.40, p b .001. Each of the four blocks explained a unique proportion of variance in PGD-scores, when entered as a first block but also when controlling for the other blocks. Most importantly, CES-scores explained a significant amount of variance (10.5%) in concurrent PGD-scores when controlling for the variance explained by the other variables. The model predicting depression-severity was also significant; F(6, 151) = 9.33, p b .001. Most importantly, CES-scores explained a unique proportion (5.6%) of the variance in depression-severity when controlling the other variables. Finally, the overall model predicting PTSD-severity was also significant; F(8, 149) = 11.36, p b .001. CES-scores again explained a significant proportion of variance in PTSDseverity (6.2%), when controlling the other variables. 1 3.4. Regression analyses predicting symptom-scores at Time 2 Next, we examined prospective associations between CES-scores at Time 1 and symptom-scores at Time 2. Three regression analyses were run, predicting PGD-severity, depression-severity, and PTSD-severity at Time 2, respectively. Predictor variables were entered in five distinct blocks representing: (i) symptom-severity at Time 1; (ii) relevant background variables (i.e. those associated with Time 2 symptom-scores); and (iii) personality indices; (iv) interpersonal closeness (IOS-scale); and (v) CES-scores tapped at Time 1. Table 3 shows the percentages of variance explained by each block, when entered as a first block to the equation, 1 DFs for the regression analyses predicting PGD, depression, and PTSD at Time 1 differ due to occasional missing values, and because the number of relevant background variables (i.e. those associated with Time 1 symptomlevels) included in the first block of each regression analysis differed between analyses.
P.A. Boelen / Journal of Affective Disorders 137 (2012) 117–124
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Table 2 Summary of regression analyses predicting symptoms at Time 1 (N = 176).
DV IVs
DV IVs
DV IVs
PGD-severity at Time 1 Block 1: background variables Education Deceased is not partner/child Unexpectedness Block 2: personality Neuroticism (TIPI) Attachment anxiety (RQ) Attachment avoidance (RQ) Block 3: closeness (IOS) Block 4: event-centrality (CES) Depression-severity at Time 1 Block 1: background variables Deceased is not partner/child Block 2: personality Neuroticism (TIPI) Attachment anxiety (RQ) Attachment avoidance (RQ) Block 3: closeness (IOS) Block 4: event-centrality (CES) PTSD-severity at Time 1 Block 1: background variables Education Deceased is not partner/child Time since loss Block 2: personality Neuroticism (TIPI) attachment anxiety (RQ) Attachment avoidance (RQ) Block 3: closeness (IOS) Block 4: event-centrality (CES)
ΔR2 when entered as first block
ΔF when entered as first block
18.4%
12.84⁎⁎⁎
21.4%
14.55⁎⁎⁎
ΔR2 when entered as last block 4.2%
18.2%
ΔF when entered as last block
20.31⁎⁎⁎
24.78⁎⁎⁎ 58.19⁎⁎⁎
3.8% 10.5%
12.57⁎⁎⁎ 35.25⁎⁎⁎
10.7%
20.76⁎⁎⁎
4.0%
8.32⁎⁎
6.1%
3.48⁎
5.4%
3.75⁎
5% 15.7%
8.78⁎⁎ 32.24⁎⁎⁎
1.4% 5.6%
2.89† 11.56⁎⁎⁎
10.5%
6.73⁎⁎⁎
4.6%
3.66⁎
5% 11.7%
13.09⁎⁎⁎
8.84⁎⁎⁎ 22.84⁎⁎⁎
14.5%
1.5% 6.2%
SE B in final model
Beta in final model
− 2.37 − 1.07 0.86
1.03 1.13 0.31
− 0.13⁎ − 0.06 0.16⁎⁎
2.29 0.02 0.33 0.95 0.61
0.33 0.12 0.12 0.27 0.10
− 2.53
.88
− 0.23⁎⁎
0.83 − 0.02 0.06 0.35 0.27
0.26 0.09 0.09 0.21 0.08
0.24⁎⁎ − 0.04 0.05 0.13† 0.27⁎⁎⁎
− 1.37 − 1.98 − 0.45
1.18 1.29 0.16
− 0.07 − 0.11 − 0.18⁎⁎
1.91 0.11 0.26 0.58 0.46
0.38 0.14 0.14 0.31 0.13
4.67⁎⁎
12.9% 25.2%
19.7%
B in final model
11.63⁎⁎⁎
3.57† 14.85⁎⁎⁎
0.41⁎⁎⁎ 0.01 0.16⁎⁎ 0.21⁎⁎⁎ 0.37⁎⁎⁎
0.34⁎⁎⁎ 0.05 0.12 † 0.13† 0.28⁎⁎⁎
Note. CES = Centrality of Event Scale. IOS = Inclusion of Other in Self Scale. PGD = Prolonged Grief Disorder. PTSD = Posttraumatic Stress-Disorder. RQ = Relationship Questionnaire. TIPI = Ten-Item Personality Inventory. † p b .10. ⁎ p b .05. ⁎⁎ p b .01. ⁎⁎⁎ p b .001.
and the percentages of explained variance when entered as last block. Regression coefficients from the final model are also shown. The model predicting Time 2 PGD-scores was significant; F(9, 80)=9.05, pb .001. Most notably, when controlling for the other variables in the equation, both initial PGD-scores (9.7%) and CESscores (2.8%) predicted a significant amount of variance in Time 2 PGD-scores. The model predicting Time 2 depression-scores was also significant; F(9, 80)=9.45, pb .001. Initial depression (10.4%) and CES-scores (5.6%) predicted a significant amount of variance in Time 2 depression-scores when controlling for the other variables. Finally, the model predicting Time 2 PTSDscores was significant; F(9, 80)=8.17, pb .001. PTSD-scores at Time 1 (15.8%) and CES-scores (4%) predicted a significant amount of variance in Time 2 PTSD-scores, above and beyond the other variables in the equation.2 2 In the six regression analyses predicting symptom-scores at Time 1 and Time 2, some of the predictor variables were highly correlated (e.g., CES-scores and symptom-scores at Time 1 in the regressions predicting symptom-scores at Time 2). For this reason, we examined collinearity statistics. These showed that, across the regression analyses, the Variance Inflation Factor never exceeded 1.4. Therefore, statistically, multicollinearity was not a concern (cf. Hair et al., 1995).
3.4.1. Additional regression analyses including additional predictor variables As noted, CES-scores varied as a function of kinship, cause of death, unexpectedness of the loss, and time since loss. All these variables were included in the regression analyses summarised above, with the exception of cause of death and time since loss. Adding these two variables as control variables to the regression analyses described above, led to no notable changes. Specifically, all reported significant associations remained significant, and all nonsignificant associations (see Tables 2 and 3) remained non-significant. There is evidence from prior studies that there are gender differences in event-centrality following negative life-events, with women experiencing such events as more central than men (Boals, 2010). We found no evidence that the impact of CES-scores on symptom-levels varied as a function of gender. That is, in six regression analyses in which the symptomscores at Time 1 and Time 2 were regressed on gender, CESscores, and the interaction between gender and CES-scores, CES-scores consistently emerged as the single significant predictor of symptom-scores.
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Table 3 Summary of regression analyses predicting symptoms at Time 2 (N = 100).
DV IVs
DV IVs
DV IVs
PGD-severity at Time 2 Block 1: PGD at Time 1 Block 2: background variables Education Deceased is not partner/child Unexpectedness Block 3: personality Neuroticism (TIPI) Attachment anxiety (RQ) Attachment avoidance (RQ) Block 4: closeness (IOS) Block 5: event-centrality (CES) Depression-severity at Time 2 Block 1: depression at Time 1 Block 2: background variables Age Deceased is not partner/child Unexpectedness Block 3: personality Neuroticism (TIPI) Attachment anxiety (RQ) Attachment avoidance (RQ) Block 4: closeness (IOS) Block 5: event-centrality (CES) PTSD-severity at Time 2 Block 1: PTSD at Time 1 Block 2: background variables Education Deceased is not partner/child Unexpectedness Block 3: personality Neuroticism (TIPI) Attachment anxiety (RQ) Attachment avoidance (RQ) Block 3: closeness (IOS) Block 4: event-centrality (CES)
ΔR2 when entered as first block
ΔF when entered as first block
41.7% 19.4%
69.96⁎⁎⁎ 7.72⁎⁎⁎
8.6%
2.79⁎
ΔR2 when entered as last block 9.7% 3.8%
1.0%
ΔF when entered as last block 15.57⁎⁎⁎ 2.06
18.10⁎⁎⁎ 23.34⁎⁎⁎
1.0% 2.8%
1.12 4.53⁎
31.1% 19.1%
44.31⁎⁎⁎ 17.57⁎⁎⁎
10.4% 5.2%
17.20⁎⁎⁎ 2.88⁎
2.11
2.6%
13.28⁎⁎⁎ 31.03⁎⁎⁎
1.0% 5.6%
1.60 9.29⁎⁎
37.2% 12.9%
58.06⁎⁎⁎ 4.72⁎⁎
15.8% 2.8%
24.31⁎⁎⁎ 1.43
10.4% 16.3%
3.10⁎
11.07⁎⁎ 19.15⁎⁎⁎
1.0%
1.0% 4.0%
Beta
in final model
in final model
0.45⁎⁎⁎
0.46
0.11
− 3.44 − 0.82 0.49
1.58 1.65 0.47
− 0.18⁎ − 0.04 0.08
− 0.06 − 0.14 0.11 0.46 0.36
0.62 0.18 0.18 0.43 0.17
− 0.01 − 0.06 0.05 0.09 0.19⁎
0.32
0.07
0.05 − 0.67 0.43
0.03 0.90 0.23
0.35 0.10 0.01 0.27 0.25
0.28 0.09 0.09 0.21 0.08
0.11 0.09 0.01 0.11 0.26⁎⁎
0.49
0.10
0.48⁎⁎⁎
− 2.04 − 0.09 0.67
1.49 1.57 0.44
− 0.01 − 0.03 0.15 0.37 0.39
0.57 0.17 0.17 0.40 0.15
0.36⁎⁎⁎ 0.14† − 0.06 0.14†
1.43
12.3% 24.0%
9.5%
SE B
in final model
0.31
16% 19.2%
6.6%
B
− 0.11 − 0.01 0.13
0.27
0.86 6.17⁎
0.00 0.02 0.07 0.08 0.22⁎
Note. CES = Centrality of Event Scale. IOS = Inclusion of Other in Self Scale. PGD = Prolonged Grief Disorder. PTSD = Posttraumatic Stress-Disorder. RQ = Relationship Questionnaire. TIPI = Ten-Item Personality Inventory. † p b .10. ⁎ p b .05. ⁎⁎ p b .01. ⁎⁎⁎ p b .001.
4. Discussion The aim of this study was to examine concurrent and prospective associations between the centrality of a loss, tapped by the CES (Berntsen and Rubin, 2006, 2007), and post-loss psychopathology. A first main finding was that, among 176 individuals, all bereaved within the past 12 months, the centrality of the loss was significantly associated with concurrent symptom-levels of PGD, depression, and bereavement-related PTSD. These findings replicate prior findings of an association between loss-centrality and post-loss psychopathology (Boelen, 2009). In addition, the findings complement prior findings of a linkage between CES-scores and post-event psychopathology observed among college-students (Berntsen and Rubin, 2006, 2007; Boals, 2010; Boals and Schuettler, 2011) and combat veterans (Brown et al., 2010).
A second main finding was that the centrality of a loss was associated with symptom-levels of PGD, depression, and PTSD one year later, among 100 participants who completed symptom-measures at this second time-point. Importantly, these associations remained significant when controlling for baseline symptom-levels and for relevant background variables. Moreover, these associations also remained significant when controlling for persistent closeness to the lost person, and indices of neuroticism and insecure attachment — variables that have all been found to be associated with poor bereavement-outcome in prior studies (cf., Boelen and Klugkist, 2011; Bonanno et al., 2002; Wijngaards-de Meij et al., 2007). The current study is the first to show that the centrality of a negative life-event is a significant predictor (and not just an epiphenomenon) of event-related psychopathology. Newby and Moulds (2011) recently examined the prospective
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linkage between the centrality of different types of negative events and depression-severity six months later among community-based individuals, some of which experienced clinical depression. In contrast with our findings, they did not find event-centrality to predict later depression, beyond baseline depression-severity. One explanation for these discrepant results is that the negative events studied by Newby and Moulds (2011) were objectively less severe, compared to the event that was the topic of the current study (bereavement). Notable also is that Newby and Moulds studied the centrality of events that were relived in intrusive memories; that is, events that were involuntarily rather than deliberately re-experienced. As Newby and Moulds argued, it is possible that the linkage between event-centrality and psychopathology is different for intrusively vs. deliberately re-experienced events. There are different pathways along which the centrality of a loss possibly contributes to the maintenance of postloss psychopathology. As noted earlier (Boelen, 2009), it is plausible that a continued sense that the lost person and his/her death are central to one's everyday inferences, life-story, and self-identity blocks access to memory information that is unrelated to the loss/lost person. Access to such information is necessary for a revision of views of the self, for creating hope for the future, and for the engagement in activities and roles that are not defined by the relationship with the lost person. Stated differently, the persistent centrality of a loss heightens accessibility of information associated with the loss, thereby blocking adjustment, and maintaining a wish to revert back to the pre-loss period, difficulties to accept the loss, and a sense that life lacks meaning — symptoms that are all hallmark features of PGD (cf., Prigerson et al., 2009). Apart from pointing at a significant linkage between losscentrality and post-loss psychopathology, the current study yielded other notable findings. Concerning the role of demographic variables, this study adds to earlier evidence that a lower educational level is associated with more problems following loss (cf., Boelen and Klugkist, 2011). With respect to loss-related variables, a notable finding was that the perceived (un)expectedness of the death was a more important predictor of post-loss distress, compared to the actual mode of death (i.e., it being violent or non-violent). Moreover, consistent with prior findings, the loss of a partner or child coincided with more severe distress than other losses (Prigerson et al., 2009). A further salient finding was that indices of neuroticism and insecure attachment did not predict later symptom-levels, beyond initial symptom-severity. This confirms assumptions made earlier, that cognitive-behavioural processes manifesting after a loss are more important determinants of bereavement-outcome than features of personality (Boelen and Klugkist, 2011). A further notable finding was that persistent closeness to the lost person seemed to contribute to concurrent and prospective symptom-levels. This adds to prior findings that persistent closeness, as well as related phenomena such as dependency in the relationship, block recovery from loss (cf., Bonanno et al., 2002). This study has several limitations. A first limitation is that the sample was composed of self-selected, predominantly relatively highly educated, middle aged individuals who have internet access. This restricts the generalisability of the results.
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As a related point, although this study did not focus specifically on bereaved women, women were overrepresented in the current study. Although there is no good explanation for this, it fits with the prior findings that women are more likely to participate in bereavement-research than are men, possibly because of women's more general willingness to reflect on their emotions (Stroebe and Stroebe, 1989). Irrespective of the exact explanation for this overrepresentation of women, in the present study this may have limited the statistical power necessary to detect gender differences in event-centrality, as observed by Boals (2010). Another limitation is that self-report measures were used to assess both dependent and independent variables. This may have inflated the relations between the two. Fourth, only few supplementary scales were used to explore the incremental validity of event-centrality. More research is needed to examine to what extent event-centrality predicts grief-related distress above and beyond non-assessed variables, including phenomenological aspects of memories related to the loss (i.e., the vividness, intrusiveness, and content of dominant memories). Notwithstanding these considerations, the present study complements prior research on the centrality of negative life-events and post-event psychopathology. The current findings have potential clinical implications. Generally stated, to the extent that the centrality of a loss contributes to emotional problems following loss, reducing such centrality should lead to better outcomes. This could potentially be achieved by helping people to clarify and review particular personal characteristics and attributes that are relatively unrelated to the lost person. Likewise, it could be useful to encourage mourners to continue valued roles and activities, specifically those that are not associated with the lost person, as a means to reduce the degree to which the loss defines the self. It could be interesting to explore the effect of such interventions on emotional distress following loss and the degree to which such effects are indeed mediated by reduction in the centrality of the loss. Role of funding source This research was supported by an Innovative Research Incentive Veni Grant (451-06-011) from the Netherlands Organization for Scientific Research (NWO) awarded to the author. NWO had no further role in study design; in the collection, analysis and interpretation of data; in the writing of the report; and in the decision to submit the paper for publication.
Conflict of interest The author declares that he has no conflicts of interest.
Acknowledgements The author thanks Hans Pieterse who assisted with the collection of data for this study.
References Aron, A., Aron, E.N., Smollan, D., 1992. Inclusion of other in the self scale and the structure of interpersonal closeness. Journal of Personality and Social Psychology 63, 596–612. Berntsen, D., Rubin, D.C., 2006. Centrality of event scale. A measure of integrating a trauma into one's identity and its relation to post-traumatic stress disorder symptoms. Behaviour Research and Therapy 44, 219–231. Berntsen, D., Rubin, D.C., 2007. When a trauma becomes a key to identity: enhanced integration of trauma memories predicts posttraumatic stress disorder symptoms. Applied Cognitive Psychology 21, 417–431.
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Boals, A., 2010. Autobiographical memories that have become central to identity: gender differences in the centrality of events scale for positive and negative events. Applied Cognitive Psychology 24, 107–121. Boals, A., Schuettler, D., 2011. A double-edged sword: the relationship between event centrality, PTSD, and posttraumatic growth. Applied Cognitive Psychology 25, 817–822. Boelen, P.A., 2009. The centrality of a loss and its role in emotional problems among bereaved people. Behaviour Research and Therapy 47, 616–622. Boelen, P.A., van den Bout, J., de Keijser, J., Hoijtink, H., 2003. Reliability and validity of the Dutch version of the Inventory of Traumatic Grief. Death Studies 27, 227–249. Boelen, P.A., de Keijser, J., van den Hout, M.A., van den Bout, J., 2007. Treatment of complicated grief: a comparison between cognitive behavioral therapy and supportive counseling. Journal of Consulting and Clinical Psychology 75, 277–284. Boelen, P.A., Klugkist, I., 2011. Cognitive behavioural variables mediate the associations of neuroticism and attachment insecurity with Prolonged Grief Disorder severity. Anxiety, Stress & Coping 24, 291–307. Bonanno, G.A., Wortman, C.B., Lehman, D.R., Tweed, R.G., Haring, M., Sonnega, J., et al., 2002. Resilience to loss and chronic grief: a prospective study from preloss to 18-months postloss. Journal of Personality and Social Psychology 83, 1150–1164. Brown, A.D., Antonius, D., Kramer, M., Root, J.C., Hirst, W., 2010. Trauma centrality and PTSD in veterans returning from Iraq and Afghanistan. Journal of Traumatic Stress 23, 496–499. Engelhard, I.M., Arntz, A., van den Hout, M.A., 2007. Low specificity of symptoms on the post-traumatic stress disorder (PTSD) symptom scale: A comparison of individuals with PTSD, individuals with other anxiety disorders and individuals without psychopathology. British Journal of Clinical Psychology 46, 449–456. Foa, E., Riggs, D., Dancu, C., Rothbaum, B., 1993. Reliability and validity of a brief instrument for assessing post-traumatic stress disorder. Journal of Traumatic Stress 6, 459–474.
Gosling, S.D., Rentfrow, P.J., Swann Jr., W.B., 2003. A very brief measure of the big-five personality domains. Journal of Research in Personality 37, 504–528. Griffin, D., Bartholomew, K., 1994. Models of the self and other: fundamental dimensions underlying measures of adult attachment. Journal of Personality and Social Psychology 67, 430–445. Hair Jr., J.F., Anderson, R.E., Tatham, R.L., Black, W.C., 1995. Multivariate data analysis, 3rd edition. Macmillan, New York. Newby, J.M., Moulds, M.L., 2011. Intrusive memories of negative events in depression: is the centrality of the event important? Journal of Behavior Therapy and Experimental Psychiatry 42, 277–283. Prigerson, H.G., Horowitz, M.J., Jacobs, S.C., Parkes, C.M., Aslan, M., Goodkin, K., et al., 2009. Prolonged Grief Disorder: psychometric validation of criteria proposed for DSM-V and ICD-11. PLoS Medicine 6 (8), e1000121. Spinhoven, P., Ormel, J., Sloekers, P.P.A., Kempen, G.I.J.M., Speckens, A.E.M., Hemert, A.M., 1997. A validation study of the Hospital Anxiety and Depression Scale (HADS) in different groups of Dutch subjects. Psychological Medicine 27, 363–370. Stroebe, M.S., Stroebe, W., 1989. Who participates in bereavement research? A review and empirical study. Omega: Journal of Death and Dying 20, 1–29. Watson, D., Clark, L.A., 1984. Negative affectivity: the disposition to experience aversive emotional states. Psychological Bulletin 96, 465–490. Wijngaards-de Meij, L., Stroebe, M., Schut, H., Stroebe, W., van den Bout, J., van der Heijden, P., Dijkstra, I.C., 2007. Neuroticism and attachment insecurity as predictors of bereavement-outcome. Journal of Research in Personality 41, 498–505. Wittouck, C., Van Autreve, S., De Jaegere, E., Portzky, G., Van Heeringen, K., 2011. The prevention and treatment of complicated grief: a metaanalysis. Clinical Psychology Review 31, 69–78. Zigmond, A.S., Snaith, R.P., 1983. The Hospital Anxiety and Depression Scale. Acta Psychiatrica Scandinavica 67, 361–370.
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Research report
A prospective examination of the association between the centrality of a loss and post-loss psychopathology Paul A. Boelen ⁎ Clinical and Health Psychology, Utrecht University, PO Box 80140, 3508 TC Utrecht, The Netherlands
a r t i c l e
i n f o
Article history: Received 26 October 2011 Received in revised form 2 December 2011 Accepted 3 December 2011 Available online 10 January 2012 Keywords: Bereavement Prolonged Grief Disorder Centrality Identity Memory
a b s t r a c t Background: Research has shown that the extent to which a negative event has become central to one's everyday inferences, life-story, and identity is associated with the severity of psychopathology experienced following this event. The current study aimed to extend this prior research by examining the prospective linkage between the centrality of a loss-event and post-loss psychopathology. Methods: To this end, 176 individuals, bereaved within the past year, completed the Centrality of Event Scale (CES) with their loss as the anchor event, together with measures of Prolonged Grief Disorder (PGD), depression, and bereavement-related Posttraumatic Stress-Disorder (PTSD) and complementary questionnaires. One hundred participants again completed symptom-measures one year later. Results: Findings showed that (a) the centrality of a loss was associated with concurrent symptom-levels of PGD, depression, and PTSD; (b) the centrality of a loss predicted PGDseverity, depression-severity, and PTSD-severity one year later, after controlling for baseline symptom-levels; (c) these cross-sectional and prospective linkages remained significant when controlling for relevant demographic and loss-related variables, as well as for indices of neuroticism, attachment anxiety, attachment avoidance and persistent closeness to the lost person. Limitations: Limitations include the under-representation of men and the reliance on selfreport measures. Conclusions: The current findings provide evidence that the centrality of a negative event is a prospective predictor of post-event psychopathology. © 2011 Elsevier B.V. All rights reserved.
1. Introduction For a minority of people, the death of a loved one precipitates the development of Prolonged Grief Disorder (PGD; Prigerson et al., 2009). PGD is a clinical condition that encompasses specific grief-reactions (including separation distress, difficulties accepting the loss and moving on without the lost person) that cause significant distress and disability at least six months after the death. Symptoms of PGD are distinct from depression and bereavement-related
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Posttraumatic Stress-Disorder (PTSD) and, if left untreated, associated with significant impairments in health and quality of life (Prigerson et al., 2009). There is growing evidence that cognitive-behavioural therapy is efficacious in the treatment of PGD and related symptoms (Boelen et al., 2007). Nevertheless, not all patients with PGD profit from this treatment (cf., Wittouck et al., 2011). It is therefore important to continue searching for mechanisms involved in the development and maintenance of PGD in order to inform refinement of PGD-treatment interventions. In literature on PTSD, there is growing interest in the concept “centrality of event” put forth by Berntsen and Rubin (2006, 2007). This concept refers to the degree to which the
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memory of a negative life-event forms a reference point for the attribution of meaning to other events, a turning point in a person's life-story, and a core component of a person's identity. It has been argued that greater event-centrality is associated with more intense post-event psychopathology, because it heightens the accessibility of memories of the event and colours the manner in which new experiences – some of which could correct erroneous conclusions about the self and future drawn on the basis of the event – are perceived and processed. Berntsen and Rubin (2006) constructed the Centrality of Event Scale (CES) to measure the centrality of event concept and found the scale to have adequate psychometric properties. A growing number of studies using the CES have found support for an association between event-centrality and post-event psychopathology. Berntsen and Rubin (2007) investigated event-centrality among college-students exposed to different kinds of negative life-events and found event-centrality to be positively associated with symptoms of PTSD, depression, and dissociation. This finding has been replicated in other student samples (Boals, 2010; Boals and Schuettler, 2011) and combat veteran samples (Brown et al., 2010). In addition, a recent study showed that the degree to which bereaved individuals experienced their loss as central was significantly associated with symptomlevels of PGD and related symptoms, even when controlling for other relevant cognitive-behavioural and personality-related variables (Boelen, 2009). A limitation of studies conducted so far is that they all relied on cross-sectional designs. Hence, research has yet to show that event-centrality is an actual predictor of event-related psychopathology and not just an epiphenomenon of such psychopathology. The current study aimed to expand prior research by examining the prospective linkage of event-centrality and post-event psychopathology, among people confronted with the death of a loved one. Specifically, individuals, all bereaved within the past year, were administered the CES and measures tapping symptoms of PGD, depression, and bereavement-related PTSD, together with complementary questionnaires (Time 1). They were invited to complete symptom-measures again one year later (Time 2). This study had two central aims. The first aim was to replicate prior findings of a cross-sectional linkage between the centrality of a loss-event and symptom-levels of PGD, depression, and PTSD, among relatively recently bereaved individuals. The second central aim was to examine the prospective linkage between the centrality of a loss and post-loss psychopathology one year later, controlling for baseline symptom-levels. Based on prior theorising (Berntsen and Rubin, 2006, 2007) we expected significant concurrent and prospective linkages to emerge. Secondary to these two central aims, we also examined the extent to which associations between event-centrality and post-loss psychopathology remained significant when controlling for background and loss-related variables that have often been found to influence grief-severity (e.g., mode of death, kinship to the deceased). Based on prior research (Boelen, 2009) event-centrality was expected to be associated with post-loss psychopathology, even when controlling for these variables.
Finally, we investigated whether or not event-centrality predicted post-loss psychopathology above and beyond personality factors of neuroticism, attachment anxiety, and attachment avoidance, and the currently experienced degree of closeness to the lost person. These variables were included because they have all been found to affect bereavementoutcome (e.g., Boelen and Klugkist, 2011; Bonanno et al., 2002; Wijngaards-de Meij et al., 2007). More specifically, neuroticism was investigated because it was deemed relevant to examine if event-centrality predicted symptomlevels beyond this general predisposition toward negative thinking and feeling (Watson and Clark, 1984). Attachment anxiety, attachment avoidance, and persistent closeness to the lost person were included to rule out that associations between the centrality of a loss and post-loss-psychopathology were accounted for by the person's generalised predisposition toward an insecure attachment style and the continuation of a sense of closeness to the lost person. Based on the notion that the CES taps into a unique phenomenon, representing the degree to which the loss has become a core part of identity, and is not just a corollary of more generic personality features and continued closeness to the lost person, we expected event-centrality to be associated with post-loss psychopathology, even when controlling for neuroticism, attachment anxiety, attachment avoidance, and persistent closeness. 2. Method 2.1. Participants and procedure Participants were recruited through announcements on Dutch Internet-sites with information about grief and bereavement in the period 2009–2010. These announcements solicited bereaved people to participate in a research programme on grief by completing questionnaires. People interested in participating were directed to a secured questionnaire on the internet or, if so wished, were sent a paper-version of the questionnaire. At Time 1, 622 questionnaires were sent out, 468 of which (75.2%) were returned. In total, 176 participants who were confronted with a loss within the preceding year were invited to complete symptommeasures of PGD, depression, and PTSD (but none of the other questionnaire measures administered at Time 1) again, approximately one year later (Time 2). One hundred participants (56.8%) did so. Because we were particularly interested in the impact of loss-centrality as experienced in the early phases of bereavement on subsequent grief, we only invited participants who were still in their first year of bereavement to compete questionnaires a second time, one year later. Those who continued to participate at Time 2 (N = 100) did not differ from those who did not (N = 76) on any of the variables that were assessed at Time 1. Data of the 176 mourners with data at Time 1 were included in the cross-sectional analyses. Data of the 100 mourners with data at Time 1 and Time 2 were included in the prospective analyses. At Time 1, N = 143 (81.2%) participants completed the questionnaires online and N = 33 (18.8%) completed a paper-version. Table 1 summarises background characteristics of the participants. Most participants were women bereaved by the loss of a partner.
P.A. Boelen / Journal of Affective Disorders 137 (2012) 117–124 Table 1 Demographic and loss-related characteristics and symptom-severity of the sample.
Demographic characteristics Gender (N (%)) Men Women Age (years) (M (SD)) Highest education (N (%)) Primary/secondary school College/university
Cross-sectional sample
Prospective sample
(N = 176)
(N = 100)
22 (12.5) 154 (87.5) 45 (12.2)
10 (10) 90 (90) 45.8 (12.1)
97 (55.1) 79 (44.9)
54 (54) 46 (46)
Loss characteristics Deceased is (N (%)) Partner 91 (51.7) Child 16 (9.1) Other relative 69 (39.2) Cause of death is (N (%)) Illness 87 (49.4) Violent (accident, suicide, homicide) 20 (11.4) Unexpected medical cause 51 (29) (e.g., heart attack) Other cause 18 (10.2) Time from loss in months (M (SD)) 4.8 (3.6) I was present at time of the death (N (%)) No 85 (48.3) Yes 89 (50.6) Unexpectedness of the death 3.1 (1.6) a (M (SD)) Symptom-scores Prolonged Grief Severity T1 (M (SD)) Prolonged Grief Severity T2 (M (SD)) Depression-severity T1 (M (SD)) Depression-severity T2 (M (SD)) PTSD-severity T1 (M (SD)) PTSD-severity T2 (M (SD))
32 (8.9) – 8.5 (5.5) – 18.6 (8.9) –
55 (55) 10 (10) 35 (35) 48 (48) 9 (9) 32 (32) 11 (11) 4.8 (3.5) 50 (50) 48 (48) 3.1 (1.6)
32.1 (8.8) 27.4 (9.1) 8.8 (5.4) 6.0 (4.7) 18.8 (8.4) 14.0 (8.6)
Note. Some numbers do not add up to N = 176 or N = 100 due to occasional missing values. PTSD = Posttraumatic Stress Disorder. a Unexpectedness was rated on a 1 = expected to 5 = totally unexpected scale.
2.2. Measures 2.2.1. PGD-scale The PGD-scale is a short version of the Inventory of Complicated Grief-revised (ICG-r), a 30 items measure of PGDsymptoms. The English (Prigerson et al., 2009) and Dutch (Boelen et al., 2003) versions of the ICG-r have adequate psychometric properties. The PGD-scale contains 11 slightly modified items from the ICG-r that resemble recently proposed criteria for PGD, including items tapping separation distress, difficulties accepting the loss, and bitterness/anger about the loss. Participants rate the occurrence of symptoms in the preceding month on 5-point scales with anchors 1 = never to 5 = always. Items are summed to form an overall PGD-severity score. The internal consistency of the scale at Time 1 was α= .89 (N= 176) and at Time 2 was α=.91 (N =100). 2.2.2. Depression subscale of the hospital anxiety and depression scale (HADS-D) The 7-item depression subscale of the HADS (Zigmond and Snaith, 1983) was used to assess depression-severity.
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Respondents rate the presence of seven depression symptoms during the previous week, on 4-point scales. The English (Zigmond and Snaith, 1983) and Dutch versions (Spinhoven et al., 1997) have yielded adequate psychometric properties. The internal consistency of the scale at Time 1 was α = .92 (N = 176) and at Time 2 was α = .91 (N = 100). 2.2.3. PTSD symptom scale self-report version (PSS-SR) The PSS-SR is a 17-item measure of PTSD. Respondents rate the frequency of symptoms on 4-point scales with anchors 0 = not at all to 3 = five or more times per week/almost always. The index event was defined as “the death of your loved one”. The English (Foa et al., 1993) and Dutch versions (Engelhard et al., 2007) have good psychometric properties. The internal consistency of the scale at Time 1 was α = .86 (N = 176) and at Time 2 was α = .89 (N = 100). 2.2.4. Relationship questionnaire (RQ) The RQ is a measure of attachment as applying to close (not necessarily romantic) relationships in general (Griffin and Bartholomew, 1994). It contains four descriptions of attachment prototypes (secure, fearful, preoccupied, and dismissing). Participants rate descriptions on 7-point scales ranging from 1 = not at all like me to 7 = very much like me. Ratings are used to obtain scores on the dimensions of attachment anxiety and attachment avoidance. The attachment anxiety score was obtained by subtracting the secure and dismissing scores from the summed fearful and preoccupied scores. The attachment avoidance score was derived by subtracting the secure and preoccupied scores from the summed fearful and dismissing scores. The RQ has adequate psychometric properties (Griffin and Bartholomew, 1994). 2.2.5. Inclusion of other in self (IOS) scale This is a single-item, pictorial measure that taps a subjective sense of interconnectedness between self and other (Aron et al., 1992). It consists of seven pairs of circles, one that includes the word self and one that includes the word other, that overlap to an increasing degree. Respondents have to select the pair that best describes their relationship with a particular person. In the current study, participants were asked to select the pair that best described their relationship with the lost person, at this moment in time. The IOS Scale has demonstrated adequate reliability and validity (e.g., strong correlations with other measures of relationship closeness) in several studies (Aron et al., 1992). 2.2.6. Centrality of event scale (CES) The CES – developed by Berntsen and Rubin (2006) – is a 7-item questionnaire, that measures the extent to which a negative life-event is central to one's everyday inferences (“This event has become a reference point for the way I understand myself and the world”), life-story (“This event permanently changed my life”), and identity (“I feel that this event has become part of my identity”). Items are rated on 5-point scales (1 = totally disagree to 5 = totally agree). In the present study, the loss of a loved one was the designated negative life-event. The CES has adequate psychometric properties (e.g., Berntsen and Rubin, 2006; Boelen, 2009). In the current study, the internal consistency was α = .84.
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2.2.7. Ten-item personality inventory (TIPI) neuroticism scale We used the 2-item neuroticism scale of the TIPI (Gosling et al., 2003) to measure neuroticism. Its two items are “I see myself as calm, emotionally stable” and “I see myself as anxious, easily upset” which are rated on 7-point scales (1 = disagree strongly, to 7 = agree strongly). The neuroticism score was the mean of the two items, after reversing scores of the former item (α = .79). The TIPI has been found to have adequate psychometric properties, including large convergence with longer measures of neuroticism (Gosling et al., 2003). 3. Results 3.1. Descriptive statistics Mean scores on the symptom-measures at Time 1 and Time 2 are shown in Table 1. Paired sample t-tests showed that symptom-levels of PGD (t(99) = 6.29), depression (t(99) = 5.89), and PTSD (t(99) = 6.40) declined significantly from Time 1 to Time 2 (ps b .001). Following guidelines provided by Prigerson et al. (2009), 32 participants (18.2%) met criteria for “caseness” of PGD. Compared with Dutch reference groups examined by Spinhoven et al. (1997), scores on the HADS-D did not differ significantly from scores of psychiatric outpatients (M=8.4 vs. M=9.3, t(175)=−1.96, p=.051). Scores on the PSS were lower than scores of 65 patients diagnosed with PTSD using a clinical interview in a study conducted by Engelhard et al. (2007). Altogether, the current sample was best described as a subclinical sample. 3.2. Variation in symptom-severity and CES scores as a function of demographic and loss-related variables We examined the degree to which scores on the symptommeasures at Time 1 (N = 176) and Time 2 (N = 100) varied as a function of demographic and loss-related variables (i.e., gender, age, education, relationship with deceased, cause of death, time since loss, being present at time of death [yes/no], and perceived unexpectedness of the death [rated on a 1 = expected to 5 = totally unexpected scale]). The participant's age was significantly correlated with depression at Time 2; r(98) = .21, p b .04. Time since loss was associated with PTSD-severity at Time 1; r(174) = −.16, p = .03. Educational level was associated with symptom-levels of PGD and PTSD at both time points; participants who went to primary/secondary school had higher scores than those who went to college or university (all Fs > 5.60, all ps b .02). Relationship with the deceased affected all symptom-scores at Time 1 and Time 2 (all Fs > 3.48, all ps b .04). Pair-wise comparisons showed that participants who had suffered the loss of a partner or child consistently had higher symptomscores compared to participants who had suffered the loss of some other loved one (ps b .05). Finally, perceived unexpectedness of the death was significantly related with Time 1 PGD-severity (r(173) = .29), and also with PGD-severity (r(98) = .26), depression-severity (r(98) = .30), and PTSDseverity (r(98) = .24) at Time 2 (ps b .02). CES-scores varied as a function of kinship (F(2, 172) = 17.90, p b .001); those confronted with the loss of a parent or child experienced the loss as more central compared to those who lost some other loved one. There was also an effect of
cause of death (F(3, 171) = 3.62, p b .02) which was due to mourners confronted with violent loss having higher CESscores than those confronted with losses due to another cause (i.e., other than illness, a violent cause, or an unexpected medical cause). Furthermore, CES-scores were positively correlated with time since loss (r(174) = .22) and unexpectedness of the loss (r(174) = .21, ps b .01) 3.3. Regression analyses predicting symptom-scores at time 1 To examine the concurrent associations of centrality of the loss (CES) with symptom-scores, three hierarchical regression analyses were conducted predicting PGD, depression, and PTSD-scores at Time 1, respectively. In each analysis, independent variables were entered in four blocks representing (i) relevant demographic and loss-related variables (i.e. those associated with Time 1 symptom-scores); (ii) personality indices (neuroticism, attachment anxiety, attachment avoidance); (iii) interpersonal closeness (IOS-scale); and (iv) CES-scores. Table 2 shows the percentages of variance explained by each block when entered as a first block to the equation, and the percentages of variance explained by each block when entered as a last block (i.e., the percentages of variance explained by each block, when controlling for the variance explained by the other three blocks). Table 2 also shows regression coefficients from the final model. The model predicting PGD-scores was significant; F(8, 148) = 23.40, p b .001. Each of the four blocks explained a unique proportion of variance in PGD-scores, when entered as a first block but also when controlling for the other blocks. Most importantly, CES-scores explained a significant amount of variance (10.5%) in concurrent PGD-scores when controlling for the variance explained by the other variables. The model predicting depression-severity was also significant; F(6, 151) = 9.33, p b .001. Most importantly, CES-scores explained a unique proportion (5.6%) of the variance in depression-severity when controlling the other variables. Finally, the overall model predicting PTSD-severity was also significant; F(8, 149) = 11.36, p b .001. CES-scores again explained a significant proportion of variance in PTSDseverity (6.2%), when controlling the other variables. 1 3.4. Regression analyses predicting symptom-scores at Time 2 Next, we examined prospective associations between CES-scores at Time 1 and symptom-scores at Time 2. Three regression analyses were run, predicting PGD-severity, depression-severity, and PTSD-severity at Time 2, respectively. Predictor variables were entered in five distinct blocks representing: (i) symptom-severity at Time 1; (ii) relevant background variables (i.e. those associated with Time 2 symptom-scores); and (iii) personality indices; (iv) interpersonal closeness (IOS-scale); and (v) CES-scores tapped at Time 1. Table 3 shows the percentages of variance explained by each block, when entered as a first block to the equation, 1 DFs for the regression analyses predicting PGD, depression, and PTSD at Time 1 differ due to occasional missing values, and because the number of relevant background variables (i.e. those associated with Time 1 symptomlevels) included in the first block of each regression analysis differed between analyses.
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Table 2 Summary of regression analyses predicting symptoms at Time 1 (N = 176).
DV IVs
DV IVs
DV IVs
PGD-severity at Time 1 Block 1: background variables Education Deceased is not partner/child Unexpectedness Block 2: personality Neuroticism (TIPI) Attachment anxiety (RQ) Attachment avoidance (RQ) Block 3: closeness (IOS) Block 4: event-centrality (CES) Depression-severity at Time 1 Block 1: background variables Deceased is not partner/child Block 2: personality Neuroticism (TIPI) Attachment anxiety (RQ) Attachment avoidance (RQ) Block 3: closeness (IOS) Block 4: event-centrality (CES) PTSD-severity at Time 1 Block 1: background variables Education Deceased is not partner/child Time since loss Block 2: personality Neuroticism (TIPI) attachment anxiety (RQ) Attachment avoidance (RQ) Block 3: closeness (IOS) Block 4: event-centrality (CES)
ΔR2 when entered as first block
ΔF when entered as first block
18.4%
12.84⁎⁎⁎
21.4%
14.55⁎⁎⁎
ΔR2 when entered as last block 4.2%
18.2%
ΔF when entered as last block
20.31⁎⁎⁎
24.78⁎⁎⁎ 58.19⁎⁎⁎
3.8% 10.5%
12.57⁎⁎⁎ 35.25⁎⁎⁎
10.7%
20.76⁎⁎⁎
4.0%
8.32⁎⁎
6.1%
3.48⁎
5.4%
3.75⁎
5% 15.7%
8.78⁎⁎ 32.24⁎⁎⁎
1.4% 5.6%
2.89† 11.56⁎⁎⁎
10.5%
6.73⁎⁎⁎
4.6%
3.66⁎
5% 11.7%
13.09⁎⁎⁎
8.84⁎⁎⁎ 22.84⁎⁎⁎
14.5%
1.5% 6.2%
SE B in final model
Beta in final model
− 2.37 − 1.07 0.86
1.03 1.13 0.31
− 0.13⁎ − 0.06 0.16⁎⁎
2.29 0.02 0.33 0.95 0.61
0.33 0.12 0.12 0.27 0.10
− 2.53
.88
− 0.23⁎⁎
0.83 − 0.02 0.06 0.35 0.27
0.26 0.09 0.09 0.21 0.08
0.24⁎⁎ − 0.04 0.05 0.13† 0.27⁎⁎⁎
− 1.37 − 1.98 − 0.45
1.18 1.29 0.16
− 0.07 − 0.11 − 0.18⁎⁎
1.91 0.11 0.26 0.58 0.46
0.38 0.14 0.14 0.31 0.13
4.67⁎⁎
12.9% 25.2%
19.7%
B in final model
11.63⁎⁎⁎
3.57† 14.85⁎⁎⁎
0.41⁎⁎⁎ 0.01 0.16⁎⁎ 0.21⁎⁎⁎ 0.37⁎⁎⁎
0.34⁎⁎⁎ 0.05 0.12 † 0.13† 0.28⁎⁎⁎
Note. CES = Centrality of Event Scale. IOS = Inclusion of Other in Self Scale. PGD = Prolonged Grief Disorder. PTSD = Posttraumatic Stress-Disorder. RQ = Relationship Questionnaire. TIPI = Ten-Item Personality Inventory. † p b .10. ⁎ p b .05. ⁎⁎ p b .01. ⁎⁎⁎ p b .001.
and the percentages of explained variance when entered as last block. Regression coefficients from the final model are also shown. The model predicting Time 2 PGD-scores was significant; F(9, 80)=9.05, pb .001. Most notably, when controlling for the other variables in the equation, both initial PGD-scores (9.7%) and CESscores (2.8%) predicted a significant amount of variance in Time 2 PGD-scores. The model predicting Time 2 depression-scores was also significant; F(9, 80)=9.45, pb .001. Initial depression (10.4%) and CES-scores (5.6%) predicted a significant amount of variance in Time 2 depression-scores when controlling for the other variables. Finally, the model predicting Time 2 PTSDscores was significant; F(9, 80)=8.17, pb .001. PTSD-scores at Time 1 (15.8%) and CES-scores (4%) predicted a significant amount of variance in Time 2 PTSD-scores, above and beyond the other variables in the equation.2 2 In the six regression analyses predicting symptom-scores at Time 1 and Time 2, some of the predictor variables were highly correlated (e.g., CES-scores and symptom-scores at Time 1 in the regressions predicting symptom-scores at Time 2). For this reason, we examined collinearity statistics. These showed that, across the regression analyses, the Variance Inflation Factor never exceeded 1.4. Therefore, statistically, multicollinearity was not a concern (cf. Hair et al., 1995).
3.4.1. Additional regression analyses including additional predictor variables As noted, CES-scores varied as a function of kinship, cause of death, unexpectedness of the loss, and time since loss. All these variables were included in the regression analyses summarised above, with the exception of cause of death and time since loss. Adding these two variables as control variables to the regression analyses described above, led to no notable changes. Specifically, all reported significant associations remained significant, and all nonsignificant associations (see Tables 2 and 3) remained non-significant. There is evidence from prior studies that there are gender differences in event-centrality following negative life-events, with women experiencing such events as more central than men (Boals, 2010). We found no evidence that the impact of CES-scores on symptom-levels varied as a function of gender. That is, in six regression analyses in which the symptomscores at Time 1 and Time 2 were regressed on gender, CESscores, and the interaction between gender and CES-scores, CES-scores consistently emerged as the single significant predictor of symptom-scores.
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Table 3 Summary of regression analyses predicting symptoms at Time 2 (N = 100).
DV IVs
DV IVs
DV IVs
PGD-severity at Time 2 Block 1: PGD at Time 1 Block 2: background variables Education Deceased is not partner/child Unexpectedness Block 3: personality Neuroticism (TIPI) Attachment anxiety (RQ) Attachment avoidance (RQ) Block 4: closeness (IOS) Block 5: event-centrality (CES) Depression-severity at Time 2 Block 1: depression at Time 1 Block 2: background variables Age Deceased is not partner/child Unexpectedness Block 3: personality Neuroticism (TIPI) Attachment anxiety (RQ) Attachment avoidance (RQ) Block 4: closeness (IOS) Block 5: event-centrality (CES) PTSD-severity at Time 2 Block 1: PTSD at Time 1 Block 2: background variables Education Deceased is not partner/child Unexpectedness Block 3: personality Neuroticism (TIPI) Attachment anxiety (RQ) Attachment avoidance (RQ) Block 3: closeness (IOS) Block 4: event-centrality (CES)
ΔR2 when entered as first block
ΔF when entered as first block
41.7% 19.4%
69.96⁎⁎⁎ 7.72⁎⁎⁎
8.6%
2.79⁎
ΔR2 when entered as last block 9.7% 3.8%
1.0%
ΔF when entered as last block 15.57⁎⁎⁎ 2.06
18.10⁎⁎⁎ 23.34⁎⁎⁎
1.0% 2.8%
1.12 4.53⁎
31.1% 19.1%
44.31⁎⁎⁎ 17.57⁎⁎⁎
10.4% 5.2%
17.20⁎⁎⁎ 2.88⁎
2.11
2.6%
13.28⁎⁎⁎ 31.03⁎⁎⁎
1.0% 5.6%
1.60 9.29⁎⁎
37.2% 12.9%
58.06⁎⁎⁎ 4.72⁎⁎
15.8% 2.8%
24.31⁎⁎⁎ 1.43
10.4% 16.3%
3.10⁎
11.07⁎⁎ 19.15⁎⁎⁎
1.0%
1.0% 4.0%
Beta
in final model
in final model
0.45⁎⁎⁎
0.46
0.11
− 3.44 − 0.82 0.49
1.58 1.65 0.47
− 0.18⁎ − 0.04 0.08
− 0.06 − 0.14 0.11 0.46 0.36
0.62 0.18 0.18 0.43 0.17
− 0.01 − 0.06 0.05 0.09 0.19⁎
0.32
0.07
0.05 − 0.67 0.43
0.03 0.90 0.23
0.35 0.10 0.01 0.27 0.25
0.28 0.09 0.09 0.21 0.08
0.11 0.09 0.01 0.11 0.26⁎⁎
0.49
0.10
0.48⁎⁎⁎
− 2.04 − 0.09 0.67
1.49 1.57 0.44
− 0.01 − 0.03 0.15 0.37 0.39
0.57 0.17 0.17 0.40 0.15
0.36⁎⁎⁎ 0.14† − 0.06 0.14†
1.43
12.3% 24.0%
9.5%
SE B
in final model
0.31
16% 19.2%
6.6%
B
− 0.11 − 0.01 0.13
0.27
0.86 6.17⁎
0.00 0.02 0.07 0.08 0.22⁎
Note. CES = Centrality of Event Scale. IOS = Inclusion of Other in Self Scale. PGD = Prolonged Grief Disorder. PTSD = Posttraumatic Stress-Disorder. RQ = Relationship Questionnaire. TIPI = Ten-Item Personality Inventory. † p b .10. ⁎ p b .05. ⁎⁎ p b .01. ⁎⁎⁎ p b .001.
4. Discussion The aim of this study was to examine concurrent and prospective associations between the centrality of a loss, tapped by the CES (Berntsen and Rubin, 2006, 2007), and post-loss psychopathology. A first main finding was that, among 176 individuals, all bereaved within the past 12 months, the centrality of the loss was significantly associated with concurrent symptom-levels of PGD, depression, and bereavement-related PTSD. These findings replicate prior findings of an association between loss-centrality and post-loss psychopathology (Boelen, 2009). In addition, the findings complement prior findings of a linkage between CES-scores and post-event psychopathology observed among college-students (Berntsen and Rubin, 2006, 2007; Boals, 2010; Boals and Schuettler, 2011) and combat veterans (Brown et al., 2010).
A second main finding was that the centrality of a loss was associated with symptom-levels of PGD, depression, and PTSD one year later, among 100 participants who completed symptom-measures at this second time-point. Importantly, these associations remained significant when controlling for baseline symptom-levels and for relevant background variables. Moreover, these associations also remained significant when controlling for persistent closeness to the lost person, and indices of neuroticism and insecure attachment — variables that have all been found to be associated with poor bereavement-outcome in prior studies (cf., Boelen and Klugkist, 2011; Bonanno et al., 2002; Wijngaards-de Meij et al., 2007). The current study is the first to show that the centrality of a negative life-event is a significant predictor (and not just an epiphenomenon) of event-related psychopathology. Newby and Moulds (2011) recently examined the prospective
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linkage between the centrality of different types of negative events and depression-severity six months later among community-based individuals, some of which experienced clinical depression. In contrast with our findings, they did not find event-centrality to predict later depression, beyond baseline depression-severity. One explanation for these discrepant results is that the negative events studied by Newby and Moulds (2011) were objectively less severe, compared to the event that was the topic of the current study (bereavement). Notable also is that Newby and Moulds studied the centrality of events that were relived in intrusive memories; that is, events that were involuntarily rather than deliberately re-experienced. As Newby and Moulds argued, it is possible that the linkage between event-centrality and psychopathology is different for intrusively vs. deliberately re-experienced events. There are different pathways along which the centrality of a loss possibly contributes to the maintenance of postloss psychopathology. As noted earlier (Boelen, 2009), it is plausible that a continued sense that the lost person and his/her death are central to one's everyday inferences, life-story, and self-identity blocks access to memory information that is unrelated to the loss/lost person. Access to such information is necessary for a revision of views of the self, for creating hope for the future, and for the engagement in activities and roles that are not defined by the relationship with the lost person. Stated differently, the persistent centrality of a loss heightens accessibility of information associated with the loss, thereby blocking adjustment, and maintaining a wish to revert back to the pre-loss period, difficulties to accept the loss, and a sense that life lacks meaning — symptoms that are all hallmark features of PGD (cf., Prigerson et al., 2009). Apart from pointing at a significant linkage between losscentrality and post-loss psychopathology, the current study yielded other notable findings. Concerning the role of demographic variables, this study adds to earlier evidence that a lower educational level is associated with more problems following loss (cf., Boelen and Klugkist, 2011). With respect to loss-related variables, a notable finding was that the perceived (un)expectedness of the death was a more important predictor of post-loss distress, compared to the actual mode of death (i.e., it being violent or non-violent). Moreover, consistent with prior findings, the loss of a partner or child coincided with more severe distress than other losses (Prigerson et al., 2009). A further salient finding was that indices of neuroticism and insecure attachment did not predict later symptom-levels, beyond initial symptom-severity. This confirms assumptions made earlier, that cognitive-behavioural processes manifesting after a loss are more important determinants of bereavement-outcome than features of personality (Boelen and Klugkist, 2011). A further notable finding was that persistent closeness to the lost person seemed to contribute to concurrent and prospective symptom-levels. This adds to prior findings that persistent closeness, as well as related phenomena such as dependency in the relationship, block recovery from loss (cf., Bonanno et al., 2002). This study has several limitations. A first limitation is that the sample was composed of self-selected, predominantly relatively highly educated, middle aged individuals who have internet access. This restricts the generalisability of the results.
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As a related point, although this study did not focus specifically on bereaved women, women were overrepresented in the current study. Although there is no good explanation for this, it fits with the prior findings that women are more likely to participate in bereavement-research than are men, possibly because of women's more general willingness to reflect on their emotions (Stroebe and Stroebe, 1989). Irrespective of the exact explanation for this overrepresentation of women, in the present study this may have limited the statistical power necessary to detect gender differences in event-centrality, as observed by Boals (2010). Another limitation is that self-report measures were used to assess both dependent and independent variables. This may have inflated the relations between the two. Fourth, only few supplementary scales were used to explore the incremental validity of event-centrality. More research is needed to examine to what extent event-centrality predicts grief-related distress above and beyond non-assessed variables, including phenomenological aspects of memories related to the loss (i.e., the vividness, intrusiveness, and content of dominant memories). Notwithstanding these considerations, the present study complements prior research on the centrality of negative life-events and post-event psychopathology. The current findings have potential clinical implications. Generally stated, to the extent that the centrality of a loss contributes to emotional problems following loss, reducing such centrality should lead to better outcomes. This could potentially be achieved by helping people to clarify and review particular personal characteristics and attributes that are relatively unrelated to the lost person. Likewise, it could be useful to encourage mourners to continue valued roles and activities, specifically those that are not associated with the lost person, as a means to reduce the degree to which the loss defines the self. It could be interesting to explore the effect of such interventions on emotional distress following loss and the degree to which such effects are indeed mediated by reduction in the centrality of the loss. Role of funding source This research was supported by an Innovative Research Incentive Veni Grant (451-06-011) from the Netherlands Organization for Scientific Research (NWO) awarded to the author. NWO had no further role in study design; in the collection, analysis and interpretation of data; in the writing of the report; and in the decision to submit the paper for publication.
Conflict of interest The author declares that he has no conflicts of interest.
Acknowledgements The author thanks Hans Pieterse who assisted with the collection of data for this study.
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