Dimensional Obsessive-Compulsive Scale

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The Dimensional Obsessive-Compulsive Scale (DOCS) is a 20-item self-report instrument that assesses the severity of Obsessive-Compulsive Disorder (OCD) symptoms along four empirically supported theme-based dimensions: (a) contamination, (b) responsibility for harm and mistakes, (c) incompleteness/symmetry, and (d) unacceptable (taboo) thoughts. [1] The scale was developed in 2010 by a team of experts on OCD led by Jonathan Abramowitz, PhD to improve upon existing OCD measures and advance the assessment and understanding of OCD. The DOCS contains four subscales (corresponding to the four symptom dimensions) that have been shown to have good reliability, validity, diagnostic sensitivity, and sensitivity to treatment effects in a variety of settings cross-culturally and in different languages. [2] [3] [4] [5] As such, the DOCS meets the needs of clinicians and researchers who wish to measure current OCD symptoms or assess changes in symptoms over time (e.g., over the course of treatment). [6]

Contents

Rationale

The DOCS was developed primarily because of the need for a measure of obsessive-compulsive (OC) symptoms that maps on to empirically established OC symptom dimensions (or "subtypes") in a conceptually consistent manner. Research consistently finds that OC symptoms distill into the following theme-based dimensions:

A second aim of the DOCS was to address important drawbacks of widely used measures of OCD (such as the Yale-Brown Obsessive Compulsive Scale [YBOCS], Obsessive Compulsive Inventory [OCI and OCI-R] [7] and Padua Inventory [PI and PI-R] [8] ). [1] [9] The limitations of these instruments include:

Accordingly, the DOCS:

Development, scoring, and evaluation

Development

Items for the DOCS were generated on the basis of research on the dimensionality of OCD symptoms [10] as well as on the parameters of OCD symptom severity. [12] After writing an initial draft of scale items and instructions, the DOCS authors obtained feedback regarding the clarity, reading level, and relevance of these materials from a larger group of (a) experts on OCD, (b) experts on scale development, and (c) people with OCD. Following the incorporation of input from these groups, the final product was a self-report instrument consisting of 20 items; five items for each of the four symptom dimensions (subscales) as described above: (a) contamination, (b) responsibility for harm, injury, or bad luck, (c) unacceptable obsessional thoughts, and (d) symmetry, completeness, and exactness. Hoarding was excluded for the reasons mentioned previously.

DOCS items were worded based on the research-supported idea that obsessions and compulsions are universal experiences, occurring in clinical and nonclinical individuals on a continuum of severity. This allows the DOCS to be viable in both clinical and nonclinical populations.

An analysis of the item reading level revealed that the DOCS is easily understandable for people aged 13–15 years and above or who read at about a 9th-grade level. [1]

Administration and scoring

Each of the four DOCS subscales begins with a general description and broad inclusive examples of the obsessions and compulsions within the particular symptom dimension. Respondents are next asked to consider any obsessions and compulsions within that symptom dimension that they have experienced within the last month and rate (on a scale from 0 [no symptoms] to 4 [extreme symptoms]) (a) the time occupied by obsessions and compulsions, (b) avoidance behavior, (c) associated distress, (d) functional interference, and (e) difficulty disregarding the obsessions and refraining from the compulsions. Thus, the DOCS subscales assesses the severity of the patient's own symptoms, rather than pre-defined symptoms as in most OCD measures. Within each subscale, the five item scores are summed to produce a subscale score (range = 0-20). The four subscale scores can be summed to produce an overall DOCS total score (range = 0-80).

A DOCS total score of 18 optimally distinguishes between someone with OCD and someone without a psychiatric diagnosis; while a score of 21 optimally distinguishes between someone with OCD and someone with an anxiety disorder. [1] As of this time, there are no empirically derived cutoff scores for mild, moderate, or severe OCD symptoms.

Psychometric evaluation

In the initial study describing the development and evaluation of the DOCS, the instrument's factorial validity was supported by exploratory and confirmatory factor analyses of 3 samples, including (a) individuals with OCD, (b) those with other anxiety disorders, and (c) non treatment-seeking individuals. Scores on the DOCS displayed excellent performance on indices of reliability (test-retest, internal consistency) and validity (convergent, divergent, construct), and the measure appears to be sensitive to treatment. The DOCS is also diagnostically sensitive and thus holds promise as a useful measure of OCD symptoms in clinical and research settings. [1]

The factor structure and psychometric properties of the DOCS have been examined in numerous studies in different cultures and languages, [2] [3] [4] [5] [15] and via different methods of administration. [16] Largely, these studies indicate that the scale's properties are consistent cross-culturally and regardless of how it is administered.

Uses and translations

Uses

As the DOCS was developed with both clinical and non-clinical samples, [1] it is suitable for use in service delivery settings as well as in research with both treatment-seeking and non-treatment-seeking samples. As it was developed and tested using adults, the DOCS is suitable for individuals age 18 and up. A version for those under 18 is currently in development.

As a self-report instrument, the DOCS requires no special skills to administer. However, interpretation of scores should be carried out by individuals with appropriate training in psychological science. When it is administered to people who have sought professional help, or who are displaying high levels of distress, interpretation should be carried out by appropriately qualified professionals such as a clinical psychologist.

The DOCS is widely used in clinical research on the nature of obsessions and compulsions. [17] [18] [19] [20] It is also used in treatment outcome studies [21] [22] as a measure to evaluate the effects of treatment for OCD.

Permission to use

The copyright for the DOCS belongs to Jonathan Abramowitz, PhD., yet the questionnaire is freely available and may be downloaded from the DOCS website. The scale may be used in paper and pencil form, or made available electronically, with the restrictions that: (a) the items and instructions are not modified, (b) it is not used or sold for profit (permission from Dr. Abramowitz is required to use the DOCS for profit), (c) it is used in unfunded research or clinical assessment in health care settings (permission from Dr. Abramowitz is required to use the DOCS in any industry sponsored clinical study), and (d) the DOCS is cited in research papers as follows:

Abramowitz, J. S.; Deacon, B.; Olatunji, B.; Wheaton, M. G.; Berman, N.; Losardo, D.; Timpano, K.; McGrath, P.; Riemann, B.; Adams, T.; Bjorgvinsson, T.; Storch, E. A.; Hale, L. (2010). "Assessment of obsessive-compulsive symptom dimensions: Development and evaluation of the Dimensional Obsessive-Compulsive Scale". Psychological Assessment. 22 (1): 180–198. doi:10.1037/a0018260. PMID   20230164.

Translations and downloads

The DOCS is now available in the following languages: English, Spanish, Japanese, Chinese, Korean, Italian, French, Icelandic, Swedish, German, Norwegian, Bengali, Dutch, Turkish, and Portuguese. All available versions of the DOCS are free to download at https://docs.web.unc.edu/downloads-and-translations/.

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References

  1. 1 2 3 4 5 6 7 8 9 Abramowitz, Jonathan S.; Deacon, Brett J.; Olatunji, Bunmi O.; Wheaton, Michael G.; Berman, Noah C.; Losardo, Diane; Timpano, Kiara R.; McGrath, Patrick B.; Riemann, Bradley C. (2010). "Assessment of obsessive-compulsive symptom dimensions: Development and evaluation of the Dimensional Obsessive-Compulsive Scale". Psychological Assessment. 22 (1): 180–198. doi:10.1037/a0018260. PMID   20230164.
  2. 1 2 Kim, Hae Won; Kang, Jee In; Kim, Seung Jun; Jhung, Kyungun; Kim, Eun Joo; Kim, Se Joo (2013). "A Validation Study of the Korean-Version of the Dimensional Obsessive-Compulsive Scale". Journal of Korean Neuropsychiatric Association. 52 (3): 130. doi: 10.4306/jknpa.2013.52.3.130 .
  3. 1 2 Melli, Gabriele; Chiorri, Carlo; Bulli, Francesco; Carraresi, Claudia; Stopani, Eleonora; Abramowitz, Jonathan (2014-08-03). "Factor Congruence and Psychometric Properties of the Italian Version of the Dimensional Obsessive-Compulsive Scale (DOCS) Across Non-Clinical and Clinical Samples". Journal of Psychopathology and Behavioral Assessment. 37 (2): 329–339. doi:10.1007/s10862-014-9450-1. ISSN   0882-2689. S2CID   145758458.
  4. 1 2 López-Solà, Clara; Gutiérrez, Fernando; Alonso, Pino; Rosado, Silvia; Taberner, Joan; Segalàs, Cinto; Real, Eva; Menchón, José Manuel; Fullana, Miquel A. (2014). "Spanish version of the Dimensional Obsessive–Compulsive Scale (DOCS): Psychometric properties and relation to obsessive beliefs". Comprehensive Psychiatry. 55 (1): 206–214. doi:10.1016/j.comppsych.2013.08.015. PMID   24209609.
  5. 1 2 Ólafsson, Ragnar P.; Arngrímsson, Jóhann B.; Árnason, Páll; Kolbeinsson, Þráinn; Emmelkamp, Paul M.G.; Kristjánsson, Árni; Ólason, Daníel Þ. (2013). "The Icelandic version of the dimensional obsessive compulsive scale (DOCS) and its relationship with obsessive beliefs". Journal of Obsessive-Compulsive and Related Disorders. 2 (2): 149–156. doi:10.1016/j.jocrd.2013.02.001.
  6. ↑ Overduin, Mathilde K.; Furnham, Adrian (2012). "Assessing obsessive-compulsive disorder (OCD): A review of self-report measures". Journal of Obsessive-Compulsive and Related Disorders. 1 (4): 312–324. doi:10.1016/j.jocrd.2012.08.001.
  7. ↑ Foa, Edna B.; Huppert, Jonathan D.; Leiberg, Susanne; Langner, Robert; Kichic, Rafael; Hajcak, Greg; Salkovskis, Paul M. (2002-12-01). "The Obsessive-Compulsive Inventory: development and validation of a short version". Psychological Assessment. 14 (4): 485–496. doi:10.1037/1040-3590.14.4.485. ISSN   1040-3590. PMID   12501574. S2CID   18815147.
  8. ↑ "Padua Inventory" (PDF).
  9. ↑ Abramowitz, Jonathan S.; Deacon, Brett J. (2006-01-01). "Psychometric properties and construct validity of the Obsessive-Compulsive Inventory--Revised: Replication and extension with a clinical sample". Journal of Anxiety Disorders. 20 (8): 1016–1035. doi:10.1016/j.janxdis.2006.03.001. ISSN   0887-6185. PMID   16621437.
  10. 1 2 3 McKay, Dean; Abramowitz, Jonathan S.; Calamari, John E.; Kyrios, Michael; Radomsky, Adam; Sookman, Debbie; Taylor, Steven; Wilhelm, Sabine (2004-07-01). "A critical evaluation of obsessive-compulsive disorder subtypes: symptoms versus mechanisms". Clinical Psychology Review. 24 (3): 283–313. doi:10.1016/j.cpr.2004.04.003. ISSN   0272-7358. PMID   15245833.
  11. ↑ Obsessive-Compulsive Disorder: Subtypes and Spectrum Conditions (1 ed.). Amsterdam; Boston: Elsevier Science. 2007-07-24. ISBN   9780080447018.
  12. 1 2 3 Deacon, Brett J.; Abramowitz, Jonathan S. (2005-01-01). "The Yale-Brown Obsessive Compulsive Scale: factor analysis, construct validity, and suggestions for refinement". Journal of Anxiety Disorders. 19 (5): 573–585. doi:10.1016/j.janxdis.2004.04.009. ISSN   0887-6185. PMID   15749574.
  13. ↑ DSM-5. American Psychiatric Association. 2013.
  14. ↑ Abramowitz, Jonathan S.; Wheaton, Michael G.; Storch, Eric A. (2008-09-01). "The status of hoarding as a symptom of obsessive-compulsive disorder". Behaviour Research and Therapy. 46 (9): 1026–1033. doi:10.1016/j.brat.2008.05.006. ISSN   1873-622X. PMID   18684434.
  15. ↑ "Psychometric validation of Dimensional Obsessive-compulsive Scale (DOCS) in Chinese college students". S2CID   148223644.
  16. ↑ Enander, Jesper; Andersson, Erik; Kaldo, Viktor; Lindefors, Nils; Andersson, Gerhard; Rück, Christian (2012). "Internet administration of the Dimensional Obsessive-Compulsive Scale: a psychometric evaluation". Journal of Obsessive-Compulsive and Related Disorders. 1 (4): 325–330. doi: 10.1016/j.jocrd.2012.07.008 .
  17. ↑ Raines, Amanda M.; Allan, Nicholas P.; Oglesby, Mary E.; Short, Nicole A.; Schmidt, Norman B. (2015). "Examination of the relations between obsessive–compulsive symptom dimensions and fear and distress disorder symptoms". Journal of Affective Disorders. 183: 253–257. doi:10.1016/j.jad.2015.05.013. PMID   26042633.
  18. ↑ Boeding, Sara E.; Paprocki, Christine M.; Baucom, Donald H.; Abramowitz, Jonathan S.; Wheaton, Michael G.; Fabricant, Laura E.; Fischer, Melanie S. (2013-06-01). "Let me check that for you: Symptom accommodation in romantic partners of adults with Obsessive–Compulsive Disorder". Behaviour Research and Therapy. 51 (6): 316–322. doi:10.1016/j.brat.2013.03.002. PMID   23567474.
  19. ↑ Wheaton, Michael G.; Mahaffey, Brittain; Timpano, Kiara R.; Berman, Noah C.; Abramowitz, Jonathan S. (2012). "The relationship between anxiety sensitivity and obsessive-compulsive symptom dimensions". Journal of Behavior Therapy and Experimental Psychiatry. 43 (3): 891–896. doi:10.1016/j.jbtep.2012.01.001. PMID   22321579.
  20. ↑ Viar, Megan A.; Bilsky, Sarah A.; Armstrong, Thomas; Olatunji, Bunmi O. (2011-03-10). "Obsessive Beliefs and Dimensions of Obsessive-Compulsive Disorder: An Examination of Specific Associations". Cognitive Therapy and Research. 35 (2): 108–117. doi:10.1007/s10608-011-9360-4. ISSN   0147-5916. S2CID   656021.
  21. ↑ Wootton, Bethany M.; Dear, Blake F.; Johnston, Luke; Terides, Matthew D.; Titov, Nickolai (2014). "Self-guided internet administered treatment for obsessive-compulsive disorder: Results from two open trials". Journal of Obsessive-Compulsive and Related Disorders. 3 (2): 102–108. doi:10.1016/j.jocrd.2014.03.001.
  22. ↑ Chase, Tannah; Wetterneck, Chad T.; Bartsch, Robert A.; Leonard, Rachel C.; Riemann, Bradley C. (2015-09-03). "Investigating Treatment Outcomes Across OCD Symptom Dimensions in a Clinical Sample of OCD Patients". Cognitive Behaviour Therapy. 44 (5): 365–376. doi:10.1080/16506073.2015.1015162. ISSN   1650-6073. PMID   25715733. S2CID   21823776.
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