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. Author manuscript; available in PMC: 2020 Jul 15.
Published in final edited form as: Cognit Ther Res. 2017 Mar 22;41:799–805.

A Preliminary Investigation of the Measurement of Object Interconnectedness in Hoarding Disorder

Mary E Dozier 1,2, Charles T Taylor 3, Natalie Castriotta 4, Tina L Mayes 1, Catherine R Ayers 1,3,4
PMCID: PMC7362991  NIHMSID: NIHMS1597580  PMID: 32669747

Abstract

A defining feature of hoarding disorder (HD) is excessive attachment to possessions. Several existing self-report measures assess emotional attachment to items but do not explicitly assess the level of interconnectedness between the individual and their items. The current study investigated a new self-report measure of object attachment based on a measure of interconnectedness among individuals. The visual nature of this measure may be especially useful in HD patients since hoarding is often characterized by low insight. Participants completed the Relationship between Self and Items (RSI) measure and measures of hoarding severity, clutter, anxiety, and depression. HD participants reported significantly higher scores on the RSI than did community controls. The RSI was positively associated with hoarding symptoms, but was not significantly correlated with symptoms of anxiety or depression. Results also suggested that the RSI is sensitive to change from pre to post-treatment. This brief, one-item measure may be useful as a screen for HD and to provide further clinical data on level of interconnectedness to possessions.

Keywords: Hoarding disorder, Interconnectedness, Anxiety

Introduction

Hoarding disorder (HD) is characterized by urges to save, difficulty discarding, and excessive household clutter (American Psychiatric Association 2013). Although there has been much speculation and research on the nature of the relationship between individuals with HD and their possessions, no studies have yet utilized any measures of interpersonal closeness between an individual and their objects. Early research on compulsive hoarding suggested a link between hoarding behaviors, increased attachment to objects (Frost and Hartl 1996), and the anthropomorphizing of possessions (Frost et al. 1996). Recent research indicates that hoarding symptoms are predictive of emotional attachment to a new object (Grisham et al. 2009) and studies utilizing non-clinical samples have found that anthropomorphism is associated with hoarding severity (Timpano and Shaw 2013), even when controlling for social anxiety symptoms (Neave et al. 2015).

A central defining feature of HD is excessive attachment to possessions (Frost and Hartl 1996). Accordingly, HD is fundamentally a relational disorder, one in which the connection between one’s self and their possessions becomes pathologic, that is, to the extent that it influences behavior and affect in ways that lead to marked functional interference and/or distress. Although the relationship between the self and one’s possessions is not unique to HD per se (Furby 1978; Pierce et al. 2003), the magnitude of this relationship is considerably inflated in individuals with hoarding-related symptoms. For example, hoarding severity has been linked to greater emotional attachment to possessions (Frost and Gross 1993; Frost et al. 1995). An experimental study in individuals diagnosed with obsessive compulsive disorder (OCD) demonstrated that the degree of initial attachment to a new item predicted subsequent attachment (1 week later; Grisham et al. 2009). Moreover, beliefs about the emotional value of possessions were associated with the degree of initial attachment to the object. Given that the connection between one’s self and their possessions is proposed to lie at the core of HD, measures assessing the relational nature of this condition are needed.

Several existing measures assess one’s perceived relationship between the self and their possessions. The Saving Cognitions Inventory-Emotional Attachment subscale (SCI-EA; Steketee et al. 2003) measures beliefs about one’s emotional attachment to their objects. The ten-item SCI-EA subscale is positively associated with hoarding severity as well as severity of anxiety and depression symptoms (Steketee et al. 2003).

The Object Attachment Questionnaire (OAQ; Grisham et al. 2009) measures emotional responses and attitudes toward possessions, and comprises items reflecting various facets of possession attachment (e.g., anthropomorphizing, identity attachment, and inflated responsibility for possessions). The 13 items of the OAQ are summed to create a global attachment index. The OAQ relates positively to the different subscales of the Saving Inventory Revised (clutter, discarding, and acquisition; SI-Frost et al. 2004) (Grisham et al. 2009; Yorulmaz and Dermihan 2015); as well as all subscales of the SCI (emotional attachment, memory, control, and responsibility) (Grisham et al. 2009). Furthermore, in a non-clinical undergraduate sample, the OAQ was found to be predictive of an individual’s ability to discard personal items (Norberg et al. 2015). Considered together, existing measures assessing relational aspects of the self and one’s possessions either focus primarily on emotional facets of attachment to items, or combine multiple aspects of item attachment into a single index rather than measuring closeness or overlap between themselves and their items.

Extant research suggests that hoarding patients may exhibit executive functioning problems (see Woody et al. 2014 for a review), suggesting the need for simplicity in assessment of HD patients. Because of this and the success of other brief pictorial measures with hoarding patients (e.g., the Clutter Image Rating; Frost et al. 2008), we endeavored to measure the relational nature of HD without including scale content related to emotions, attitudes, or reasons underlying the attachment between self and items (e.g., anthropomorphizing, inflated responsibility). To accomplish this goal, we piloted a single-item pictorial measure intended to assess HD patients’ sense of being interconnected with their possessions, the Relationship between Self and Items (RSI) scale.

The RSI is an adaptation of the Inclusion of Other in Self scale (IOS; Aron et al. 1992), a one-item pictorial measure that visually depicts the relationship between one’s self and another target (i.e., person) as a way to measure interrelatedness. The original IOS scale asks respondents to select the picture that best describes their relationship with their “closest other” person (e.g., spouse, friend) from a set of Venn-like diagrams each representing different degrees of overlap of two circles. The development of the IOS was founded on the notion that interpersonal “closeness” is reflected in overlapping, i.e. interconnected, selves (Aron and Aron 1986; Aron et al. 1991). That is, in close relationships the individual may perceive the self as including characteristics of the other. Drawing on this theoretical foundation, we adapted the IOS to measure the relationship between one’s self and their items. In keeping with the original IOS, the RSI depicts as a series of seven overlapping circles, one labeled ‘Self’ and the other labeled ‘Items’ (see Fig. 1). The degree of overlap progresses linearly, creating a seven-step, interval-level scale. The instructions included in the RSI mirror those of the IOS (Aron et al. 1992), but with the added specification that participants are rating their relationships with their items (Fig. 1).

Fig. 1.

Fig. 1

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Relationship between Self and Items (RSI) Scale Instructions: Please circle the picture that best describes your current relationship with your items

The goal of the current investigation was to pilot the RSI in a community sample and in a sample of individuals meeting criteria for HD, and to explore the application of the RSI as a brief, easy to administer measure representing one’s perceived relationship between the self and their items. Our first aim was to examine descriptive statistics of the RSI (e.g., mean, variability) in an HD sample and in a sample of unselected participants recruited from the community. Our second aim was to explore the relationships between the RSI, hoarding symptoms, anxiety and depression, and social desirability. We hypothesized that higher degrees of interconnectedness between self and items on the RSI would be positively related to higher degrees of acquisition and difficulty discarding one’s possessions, but would be unrelated to symptoms of anxiety and depression or social desirability. We also explored the relationship between the RSI and an established measure of emotional attachment in a subset of participants. Finally, to explore sensitivity to change, we examined changes in RSI scores from pre to post-treatment for HD.

Methods

The HD sample utilized baseline and post treatment data from 77 individuals enrolled in two individual (n = 54) or one group (n = 30) treatment outcome studies between September 2013 and December 2017. Inclusion criteria for all HD studies required that participants meet DSM-5 criteria for HD. Participants in one of the individual studies (n = 12) were further required to be at least 60 years of age, to have made no changes to psychiatric medications for the previous three months, and to not meet criteria for active substance use disorders, psychotic disorders, or bipolar I or II disorder. Participants in the second individual study (n = 42) were required to be Veterans. Participants in the community control sample (n = 30) were recruited in person from outside of public locations, including community centers, parks, and grocery stores. Verbal and written informed consent was obtained from all HD participants; community control participants provided verbal informed consent only. All study procedures were approved by the local institutional review board.

A copy of the RSI as administered to participants in the current study is presented in Fig. 1. The RSI was constructed to resemble the IOS (e.g., seven Venn diagrams of linearly increasing overlap), with the exception that the circles remain the same size for each answer choice. Participants were provided with written instructions (“Please circle the picture that best describes your current relationship with your items.”) and the RSI was administered as part of the larger self-report battery in all HD studies. Community control participants were administered the RSI as part of a one page survey that also included age, gender, and the five-item Hoarding Rating Scale (HRS; Tolin et al. 2010).

Hoarding symptom severity was assessed using the Saving Inventory-Revised (SI-Frost et al. 2004) and the Clutter Image Rating (CIR; Frost et al. 2008). The SI-R is a 23 item self-report measure with three subscales: acquisition, difficulty discarding, and clutter. The SI-R demonstrated adequate reliability in the HD sample for the total score (α = 0.83) and all subscale scores (acquisition: α = 0.76; difficulty discarding: α = 0.82; clutter: α = 0.91). The HRS was also administered to a subset (n = 43) of the HD sample and demonstrated adequate reliability in the HD sample (α = 0.88).

The CIR is a three item pictorial measure in which the participant indicates the clutter levels of their living room, kitchen, and bedroom by choosing which of nine pictures of increasing clutter levels best matches the corresponding room in their home. The CIR has strong inter-rater reliability between patient and clinician ratings (Frost et al. 2008; Dozier and Ayers 2015) and had adequate internal consistency in the HD sample (α = 0.83). The mean CIR score was used in the current study.

The 23-item Savings Cognition Inventory (SCI) was administered to a subset of the HD sample (n = 20) to assess self-reported emotional attachment to items. The SCI includes four subscales: Emotional Attachment, Control, Responsibility, and Memory. The SCI Total score demonstrated strong reliability in the HD sample (α = 0.87).

Psychiatric symptoms were assessed using the Hospital Anxiety and Depression Scale (HADS; Zigmond and Snaith 1983), a 14-item self-report measure composed of two scales which assess anxiety and depressive symptoms. The HADS demonstrated adequate reliability in the current sample (Anxiety: α = 0.86; Depression: α = 0.85). Social desirability was assessed using the 20-item version of the Marlowe-Crowne Social Desirability Scale (MC-SDS; Crowne and Marlowe 1960; Strahan and Gerbasi 1972). The MC-SDS demonstrated adequate reliability in the current sample (α = 0.85). The HADS and MC-SDS were only administered to a subset of the HD sample (n = 43).

All analyses were performed using Stata version 13.0 (StataCorp 2013). The relationships between baseline RSI scores and all study variables were examined using zero-order correlations and unpaired Welch’s t tests to account for unequal variance. Sensitivity to change was explored through the comparison of baseline and post treatment scores on the RSI. An alpha level of p < .05 was used to indicate significant findings.

Results

Participants in the HD group were mostly female (55%), Caucasian (71%), and unmarried (71%). The HD sample was largely composed of older adults, with 64% of the sample being aged 60 or older (mean age: 61.83, SD = 10.75, range 26–82). Participants in the community control group had a mean age of 42.8 (SD = 18.0; range 20–78) and were mostly female (57%). Participants in the HD group tended to be older than the community control participants [t (37.16) = −5.46, p < .0001], but there were no group differences on gender [χ2 (1) = 0.032, p = .857].

The mean HRS score for the community control group was 1.36 (SD = 1.1; range 0-3.8), which was significantly lower than the mean HRS score for the HD group (5.24, SD = 1.76; t (71.58) = −12.50, p < .0001). Participants in the HD group (n = 84) reported an average baseline RSI score of 4.68 (SD = 1.91). The average RSI score in the community control group (n = 30) was 2.9 (SD = 1.2). The mean RSI score in the community control group was significantly lower than the mean RSI score in the HD group [t (83.88) = −5.84, p < .0001]. Within the HD group, the baseline RSI was unrelated to all demographic variables [age: r = −.13, p = .244; gender: t (72.95) = 0.54, p = .297; currently married: t (41.41) = −0.12, p = .453; Caucasian (t (51.93) = 0.77, p = .222)]. The RSI was also unrelated to the demographic variables collected in the community control group (age: r = −.04, p = .819; gender: t (26.74) = 1.12, p = .137).

Zero-order correlations among study variables are presented in Table 1. The baseline RSI was significantly correlated with the SI-R Total (r = .25, p = .02) and SI-R difficulty discarding (r = .37, p = .016), but was not significantly correlated with the SI-R clutter subscale (r = .11, p = .321), the SI-R acquisition (r = .17, p = .118) or the CIR (r = −.01, p = .916). Baseline RSI scores were not significantly correlated with the HADS Anxiety (r = .05, p = .734) and Depression subscales (r = .25, p = . 103) or with the MC-SDS (r = .10, p = .516). In the subset of participants who completed the SCI (n = 20), baseline RSI scores were not significantly correlated with the SCI Total (r = .28, p = .226) or with any of the SCI subscale scores (Emotional Attachment: r = .25, p = .296; Control: r = .39, p = .087; Responsibility: r = .19, p = .411, Memory: r = .14, p = .570). Post hoc analyses were run to explore the individual association between the RSI and the individual items of the SCI emotional attachment scale. All associations were nonsignificant (all ps > 0.05) with the exception SCI item 10: “I see my belongings as extensions of myself; they are part of who I am.” The RSI was significantly correlated with this item (r = .62, p = .004).

Table 1.

Baseline means, standard deviations, and zero-order correlations among study variables in 84 adults with hoarding disorder

1 2 3 4 5 6 7 8 Mean SD
1. RSI – 4.68 1.91
2. SI-R total .25* – 59.19 13.65
3. SI-R clutter .11 .83*** – 24.32 7.45
4. SI-R difficulty discarding .37* .80*** .53* – 19.26 5.43
5. SI-R acquisition .17 .72*** .32** .51*** – 15.51 5.12
6. CIR −.01 .46*** .56*** .28 .13 – 3.79 1.65
7. HADS anxietya .05 .44*** .29* .35** .31* .23 – 9.48 5.36
8. HADS depressiona .25 .58*** .39** .54*** .33** .32* .63*** – 8.12 4.61
9. MC-SDSa .10 −.25 −.03 −.24 −.35* .19 −.09 −.29 9.56 4.76
10. SCI totalb .28 .32 .10 .34 .35 −.25 – – 94.4 22.74
11. SCI emotional attachmentb .25 .35 .19 .23 .41 −.16 – – 37.00 13.49
12. SCI controlb .39 .16 .02 .21 .19 −.20 – – 15.80 4.21
13. SCI responsibilityb .19 .22 .04 .48* .04 −.08 – – 24.60 7.56
14. SCI memoryb .14 .04 −.14 .05 .28 −.48 – – 21.05 5.54
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SI-R Saving Inventory-Revised, CIR Clutter Image Rating, HADS Hospital Anxiety and Depression Scale, MC-SDS Marlowe-Crowne Social Desirability Scale, SCI Saving Cognition Inventory

***

p < .001

**

p < .01

*

p < .05

a

These measures were only administered to a subset (n = 43) of the HD sample

b

The SCI was only administered to a subset (n = 20) of the HD sample

A multiple regression analysis was conducted post hoc to investigate the unique contribution of the RSI in predicting scores on the SI-R Total when controlling for depression symptoms. This analysis was conducted using only the subset of HD participants who completed the HADS (n = 43). The overall model including the RSI and the HADS Depression subscale was significant [F (2,40) = 18.42, p < .0001, R2 = 0.479]. There was a modera te but not statistically significant partial correlation between RSI and SI-R Total when controlling for HADS Depression subscale (r = .25, p = .114).

Of the 84 individuals who completed the RSI at baseline, 30 participants also completed the RSI, HADS, SI-R, and CIR at post treatment assessment, six months after the baseline assessment. Because the current study took place in the context of three larger treatment outcome studies, these participants were from four treatment conditions: individual Cognitive Rehabilitation and Exposure/Sorting Therapy (CREST) (n = 4), group CREST (n = 8), individual geriatric case management (n = 3), and group exposure therapy (n = 15). Using the subsample of 30 individuals who completed the RSI at both baseline and post treatment, the RSI demonstrated sensitivity to change: overall, participants’ post assessment scores were significantly lower than their baseline scores [t (29) = 4.7, p < .0001]. The mean difference was 1.6 points, from 4.9 to 3.3. Participants also reported significant decreases in symptom severity on the HADS Depression subscale [t (29) = 2.64, p = .007], the SI-R Total [t (29) = 5.92, p < .0001], and the CIR [t (22) = 2.21, p = .019]. Change in RSI score from baseline to post-treatment was significantly correlated with change in SI-R symptom severity (r = .46, p = .01), but was unrelated to change on the HADS Depression subscale (r = .26, p = .169) or change on the CIR (r = .24, p = .262).

Discussion

The current study explored the utility of a single-item pictorial measure designed to capture the core relational feature of HD—the interconnectedness between one’s self and their possessions—in a well-characterized sample of individuals meeting diagnostic criteria for HD. The RSI complements existing attachment measures by examining interconnectedness with items. Furthermore, due to the brief nature of the RSI, it may be useful as an initial screening tool or as an adjunct to an already lengthy assessment battery.

The pattern of correlations with existing measures of hoarding symptoms as well as measures of anxiety and depression supported the utility of the RSI to assess hoarding severity. When controlling for symptoms of depression, the RSI predicted 6% of the variance on the SI-R Total. Because this analysis was run on a subsample of participants, the observed medium-sized effect was not statistically significant, underlining the importance of replicating the results of the current study in larger samples. Moreover, the RSI demonstrated sensitivity to change in the context of established treatment regimens for HD. Collectively, these findings provide initial support for the RSI as a brief relational measure of HD.

There is much speculation in the hoarding literature about the relationship between hoarding patients and their possessions (e.g., Frost and Hartl 1996). The RSI reflects an adaptation of a social relationship measure for use in a hoarding sample to query patients’ relationships with their items. A major strength of the RSI is its ability to capture variance in hoarding severity measures that is unique to hoarding symptoms. The lack of relationship between the RSI and baseline clutter is consistent with the results of previous studies looking at the disparate pattern of relationships among self-reported symptoms of hoarding (e.g., difficulty discarding and urges to save) and clutter with other self-report or behavioral symptoms (Ayers et al. 2016; Dozier et al. 2015). The results of the current study also demonstrate that the RSI is not susceptible to social desirability. Although the association between the RSI and the SCI was not statistically significant, the medium effect sizes observed between the RSI and the SCI Total and Emotional Attachment subscale suggest initial convergent validity while also suggesting that the RSI may be measuring a partially distinct construct.

Although other measures have been designed to capture similar aspects of hoarding as the RSI, such as the SCI and the OAQ, these measures require participants to process verbal information and to decide the degree to which each statement is true for him or herself. As suggested elsewhere (Aron et al. 1992), diagrams illustrating relational constructs in this way may bypass verbally encoded relational schemas and instead activate a more deeply structured sense of self-item relatedness.

The RSI was sensitive to change following established treatment regimens for HD. These findings may have important clinical implications. The RSI may provide clinicians with a brief tool to detect changes in key features of HD. Additionally, the current investigation suggests that the way in which an individual with HD conceptualizes themselves in relation to their possessions changes as a result of exposure based treatment for hoarding. Targeting beliefs about self and possessions may be a mechanism of effective treatment; further research is needed to determine if reducing attachment to possessions leads to a reduction in symptoms.

Limitations

Although the current study provided an initial validation of the RSI for examining the degree of closeness that hoarding patients feel with their possessions, there were several limitations. First, the majority of the participants were older, female, and Caucasian, which limits the generalizability of the findings. In samples with a more inclusive age range, age may be significantly associated with the RSI. Furthermore, the control group used in the current study was recruited from the community and was not administered a full diagnostic battery. Future investigations of the RSI should consider including a psychiatric control group or a more thoroughly vetted community control sample. Next, the sample administered the SCI (n = 20) was underpowered to detect a significant correlation between the RSI and the SCI Total and Emotional Attachment scales. The analyses conducted using the SCI should be replicated in larger samples before any definitive conclusions can be made.

Finally, there was no investigation of how participants interpreted the RSI. The original IOS validation study indicated that individuals interpret the IOS in terms of “interconnectedness” between the participant and their closest other (Aron et al. 1992). Given that the RSI and IOS are conceptually and structurally similar, it is likely that participants in the current study had a similar interpretation of the RSI (e.g., the interconnectedness between themselves and their possessions). However, it is possible that some participants had alternate interpretations of the measure, such as the physical overlap of their life with their objects (e.g., clutter level). Future studies attempting to validate the RSI could include a focus group to query for common themes in interpretation of the assessment and consider piloting alternate sets of instructions, such as asking the participant to rate their relationship with their most important (or most valued) possessions.

Acknowledgments

Funding This study was funded by the Clinical Science R and D Program of the Veterans Health Administration (CSRD-068-10S and CLNA-005-14S). The contents do not reflect the views of the Department of Veterans Affairs or the United States Government.

Footnotes

Conflict of Interest Mary E. Dozier, Charles T. Taylor, Natalie Castriotta, Tina L. Mayes, and Catherine R. Ayers declare that they have no conflict of interest.

Informed Consent All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Informed consent was obtained from all individual participants included in the study.

Animal Rights This article does not contain any studies with animals performed by any of the authors.

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